Platypus PLC Modem Intelligent media bridge

Transcription

1 USER MANUAL Platypus PLC Modem Intelligent media bridge Document revision: Issue date: September 19, 2016

2

3 CONTENTS 1 Introduction Device Overview Indicator LEDs Product Label Wire Terminal Reference 3 3 Configuration System Requirements Using Firefox + Copper (Cu) Additional Operations Configuration Variables Reference GPIOs GPIO Variable Reference Serial Bridge Configuring the Endpoints Baud Rate Buffering Serial Bridge Configuration Variables Reference See Also IPv6 Networking Routing from PC to PC Ping Test Platypus User Manual Theobroma Systems Design und Consulting GmbH Page i

4 7 DMX Enable DMX Mode Sending DMX Data DMX Configuration Variables Reference See Also Firmware Update 22 9 Factory Reset Advanced Configuration Manual Route Setup on Linux Mechanical Dimensions Changelog Open Source Licenses microcoap RIOT OS Page ii

5 CHAPTER ONE INTRODUCTION Congratulations for acquiring one of the most advanced narrowband-powerline-communications modem on the market. This user manual provides comprehensive information of all features of the Platypus PLC modem. 1.1 Device Overview Platypus has its C8-shape AC connector on one end. It is used both for power supply of the device and for data transfer via powerline communications. The other end (shown below) hosts a Micro-USB connector and seven wire terminals. The wire terminals are numbered 1 to 7, with 1 being closest to the Micro-USB connector. Activity System Status SYS ACT Wire Terminals Micro-USB Figure 1.1: Platypus front view Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 1

6 1.2 Indicator LEDs The System Status LED shows the current state of the powerline connection. System Status LED Description blinks yellow booting up blinks blue trying to connect to the powerline network blinks purple connection established The Activity LED indicates traffic on the power line. Activity LED Description flashing blue traffic on the powerline network 1.3 Product Label The product label on the bottom of each Platypus device shows information that is personalized for each unit. The Serial Number identifies each unit uniquely. The USB IP is the IPv6 address that is used to access Platypus through a direct USB connection. The PLC IP is used to access the Platypus device through the powerline network. Serial Number PLATYPUS V~ 50Hz 50mA USB: PLC: fd2a:0:0:32de::1 fd2a::9e14:32de USB IP PLC IP Figure 1.2: Platypus product label Note: Both the USB IP and the PLC IP can be changed through configuration variables. The label shows the default values. You can always revert to the default values by performing a factory reset (see section Factory Reset) Page 2

7 CHAPTER TWO WIRE TERMINAL REFERENCE Functions are mapped as follows (see the figure Terminal numbering for the ordering. Terminal 1 is closest to the Micro-USB port). Terminal # Function Level 1 RS-485 B- -7 to +12V to GND 2 RS-485 A+ -7 to +12V to GND 3 GND 4 ADC input or digital GPIO (input or output) 3.3V 5 Analog output 0-10V 6 Supply voltage output 3.3V 100mA 7 Digital GPIO (input or output) 3.3V The RS485 pins 1 and 2 are protected against overvoltage up to +-14 Volts. The 3.3V output at pin 6 is designed to provide up to 100mA for external circuitry. It is protected with an internal PTC fuse that limits the short-circuit current to about 300mA. Drawing more than 100mA will cause the output voltage to drop signifcantly. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 3

8 Micro USB Figure 2.1: Terminal numbering Page 4

9 CHAPTER THREE CONFIGURATION When setting up a network, you must configure one device as the coordinator. This device must be configured through a direct USB connection. Once the coordinator is active, other Platypus devices will automatically connect to it (the System Status LED will switch to purple). You can then connect to any Platypus device via USB to configure any Platypus device in the network through the PLC IP. 3.1 System Requirements To configure Platypus, you need a computer running either Windows 7, 8 or 10 with the Platypus driver installed (download the driver from Linux (any distribution, no drivers needed) On both platforms, you need Mozilla Firefox with the Copper (Cu) add-on (install at Note: Platypus uses the standard CoAP protocol for configuration. Instead of Firefox with the Copper add-on, you can use any standards-compliant CoAP client. On Windows, Platypus will show up in the Network Connections control panel. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 5

10 Figure 3.1: Network Connections control panel 3.2 Using Firefox + Copper (Cu) To promote a Platypus to the coordinator, you set the coord variable to 1. The steps to do so are listed below and shown on figure Steps to configure Platypus as a coordinator. The process to set any other configuration variable is identical apart from step (3). 1. Enter the prefix coap:// and the USB IP in square brackets into the Firefox address field. In our example, the complete address is: coap://[fd2a:0:0:9624::1]. Press enter to submit the address. 2. Click Discover to populate the list of available configuration variables on the left 3. Click the coord entry on the left, located in the net/plc folder 4. Select the Outgoing tab 5. Enter 1 in the text field 6. Click PUT. Firefox displays the status code 2.04 Changed indicating that the operation was successful. For the change to take effect, restart Platypus by unplugging and re-plugging the USB cable. The System Status LED will blink purple. 3.3 Additional Operations To read the current value of a variable, select it on the left and click GET. The value is displayed in the Incoming tab. Page 6

11 Figure 3.2: Steps to configure Platypus as a coordinator Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 7

12 Platypus can be restarted remotely by setting the reboot variable, located in the sys folder, to 1. After 5 seconds, Platypus will restart. If you prefer using a command-line client, libcoap ( is a BSD-licensed CoAP library that includes the coap-client command-line tool. 3.4 Configuration Variables Reference Folder Variable Read/ Write Default Description.well-known core R Contains the list of available folders and variables. This is used by the Copper CoAP client to generate the tree in the sidebar on the left. The format is specified in RFC6690. gpio Options for the two GPIOs. This folder is described in the section GPIOs. net/plc PLC networking configuration. attenuation RW 3 Transmitter attenuation. The range is 3 to 27dB, in 3dB steps. coord RW 0 Set to 1 if you want this device to be the PLC coordinator, 0 otherwise. iid RW Printed on label IPv6 interface identifier (the lower half of the PLC IP address). Example: ::9815:a1f7 link-state R Status of the PLC connection. 0 = disconnected. mac RW Randomly generated Sets the MAC address that is used internally on the PLC network. panid RW 1f PAN ID of the PLC network the Platypus should join or create (if configured as coordinator). prefix R(W) fd2a:: IPv6 subnet prefix that is used on the PLC interface. This option is only writeable if the device is configured as the coordinator. net/usb USB network interface configuration. host-mac RW Randomly MAC address of the PC on the USB interface. generated platypus-ip RW Printed on IPv6 address of the Platypus on the USB interface. label platypus-mac RW Randomly generated MAC address of the Platypus on the USB interface. Page 8

13 Folder Variable Read/ Write Default Description rs485 Configuration for the RS-485 interface. bridge Serial bridge options. The available options are described in section Serial Bridge. dmx DMX related options - described in section DMX. function RW bridge Sets the active function of the RS-485 interface to either bridge or dmx mode. sys System software options. cpu-id R The 12-byte long CPU ID that is burned into the microcontroller. This value is globally unique and immutable. Printed as 2-byte hex pairs, separated by spaces. Example: udpgen 38ff d factory-reset W Writing 1 resets the configuration to factory defaults. See section Factory Reset for details. find-me W Writing any value blinks the SYS LED rapidly yellow for 5 seconds. This function can help to identify the Platypus that corresponds to a known IP address. firmwareversion R Version of the currently running firmware. license R Platypus incorporates code from open source projects. Their licenses are shown here. reboot W Write 1 to reboot the device. The dummy traffic generator sends UDP packets to the all-nodes multicast address. This can be useful when analyzing channel attenuation. datalen RW 256 UDP payload length in each packet, 1 to 256 bytes. interval RW 0 Interval between packets, in milliseconds. The valid range is 1 to Setting to 0 disables the traffic generator. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 9

14 CHAPTER FOUR GPIOS Platypus provides two 3.3V-level GPIOs, GPIO 4 on terminal 4 and GPIO 7 terminal 7. Both can work as digital inputs and outputs. GPIO 4 can also be used as an ADC input. GPIO 5 is a 0 to 10V analog output. GPIOs are configured, read and written through configuration variables. The folder gpio/4 contains the variables for GPIO 4, gpio/5 for GPIO 5 and gpio/7 for GPIO 7. The folders each contain the variables mode and value. For GPIO 4 and 7, mode can be set to either in - digital input out - digital output GPIO 4 can additionally be set to adc - ADC (analog input, 3.3V maximum) The table below summarizes the available modes: GPIO Default mode Alternate 1 Alternate 2 4 in out adc 5 dac in out - In digital mode, value is either 0 or 1. In ADC mode, value is the currently measured voltage, in millivolts. For GPIO 5, value can be set to 0 to millivolts. Page 10

15 4.1 GPIO Variable Reference Folder Variable Read/Write Default Description gpio/4 mode RW in Possible values: in, out, adc value R(W) 0 The current value of the GPIO. In input and ADC mode, this variable is not writable. In adc mode, value is the measured voltage in millivolts. gpio/5 mode R dac Fixed to dac mode value RW 0 Output voltage in millivolts, 0 to gpio/7 mode RW in Possible values: in, out value R(W) 0 The current value of the GPIO. In input mode, this variable is not writable. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 11

16 CHAPTER FIVE SERIAL BRIDGE Platypus can act as a transparent RS485 serial bridge. Bidirectional communication is forwarded over the power line. Baud rate and parity can be freely configured through CoAP. Powerline network RS485 RS485 Figure 5.1: Transparent RS485 bridge Every Platypus integrates an RS485 serial transceiver. Terminals 1, 2 and 3 are used as show below B- A+ GND Figure 5.2: RS485 terminals Page 12

17 5.1 Configuring the Endpoints As a powerline network may contain many Platypus devices, the endpoints of the serial bridge must be defined by the user. This is done by connecting to each of the Platypus bridge pair units and setting the target-ip variable. This variable is located in the rs485/bridge folder. It should be set to the PLC IP of the other end. The default PLC IP is printed to the bottom of each Platypus device. An example configuration is shown below. Device PLC IP target-ip setting Platypus 1 fd2a::9e14:32de fd2a::5ecd:f6d3 (IP address of Platypus 2) Platypus 2 fd2a::5ecd:f6d3 fd2a::9e14:32de (IP address of Platypus 1) 5.2 Baud Rate Set the baud rate by writing the baudrate variable. Virtually all baud rates from 600 to are supported. Support for these standard baud rates is guaranteed: (default setting) Buffering Platypus receives single bytes at a time from RS-485. PLC on the other hand is packet-oriented, transmitting up to 1280 bytes at a time. Each packet has a header and a certain transmission overhead. Sending few bigger packets is more efficient than sending many small packets. Platypus reads bytes from the RS-485 interface and stores them in an internal buffer until any of three conditions is met. Only then it sends out the buffered data (if any) in a PLC packet. The conditions are: Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 13

18 Condition Description Configuration Variable Buffer full The buffer has been filled with L bytes. The number L can be buffer-len configured in the buffer-len variable. Timeout At least T milliseconds have passed since the last byte has been timeout received. The number T can be configured in the timeout variable. End-of-line An end-of-line (eol) character has been received. What counts eol as an eol character can be configured in the eol variable. Default Setting 256 bytes 500 milliseconds Line feed (0a) and carriage return (0d) The default buffering configuration has been tuned to be robust and suitable for a wide range of use-cases, including interactive terminals. All available configuration variables are described in the section ref :sb-var-ref. Example configurations for a few select special use-cases are shown below. Sensor periodically sending out values terminated with ; : Configuration Setting Comment Variable buffer-len 256 This could be lowered to the maximum expected length of the value the sensor sends out. But there is no harm in keeping it at the maximum. timeout 0 Never send out the packet before receiving the ;. This makes sure the other end never receives partial values. eol 3b ASCII code for ;. Device reporting its status every 10 seconds in three status bytes: Configuration Setting Comment Variable buffer-len 3 Send the packet after receiving a three-byte status message. timeout 5000 Setting the timeout to half the expected interval makes sure that packet boundaries resynchronise to the message boundaries in every case. eol The device does not send any end-of-line indicator, set to an empty value. Device sending line-feed terminated messages: Configuration Setting Comment Variable buffer-len 256 This could be lowered to the maximum expected length of the value the sensor sends out. But there is no harm in keeping it at the maximum. timeout 0 Never send out partial messages eol 0a ASCII code for line feed Page 14

19 5.4 Serial Bridge Configuration Variables Reference Folder Variable Read/ Write Default Description rs485/ bridge All options concerning serial bridging are grouped in the rs485/bridge folder. baudrate RW 9600 Serial baudrate, 110 to buffer-len RW 256 Maximum number of bytes in the buffer. Range eol RW 0a0d End-of-line character, string of hex values (up to 15). Example denoting LF or $: 0a24 parity R 2 n Parity Bit: n -> none e -> even parity o -> odd parity rs485-output R 1 1 Disable (0) or enable (1) outputting data on the RS485 terminals. This can be used to implement a listen-only function. stopbits R 1 1 Number of stop bits used, 1 or 2. target-ip RW :: The IPv6 address the serial data is sent to. Set to :: to disable sending. timeout RW 500 RS-485 receive timeout, in milliseconds. Valid range is 1 to (= 1 minute). Set to 0 to disable the timeout. 5.5 See Also Platypus Application Note AN50702 shows how to create a serial bridge between two Windows computers running PuTTY. 1 Currently read-only. Will become writable in a future revision. 2 Currently read-only. Will become writable in a future revision. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 15

20 CHAPTER SIX IPV6 NETWORKING Each Platypus is an IPv6 router. It exposes a standard 1 USB network card on the Micro-USB port. Two or more computers connected to the powerline network can communicate through standard IPv6 packets with arbitrary data. Platypus has two IP addresses because it has two network interfaces: USB and PLC (powerline). Both addresses are printed on the label of each device, the USB IP and the PLC IP, as described in the chapter Introduction. PC IP fd2a:0:0:32de:w:x:y:z USB PC Powerline network PC IP fd2a:0:0:bc87:w:x:y:z USB PC fd2a:0:0:32de::1 USB IP fd2a::9e14:32de PLC IP fd2a::e9af:bc87 PLC IP fd2a:0:0:bc87::1 USB IP Figure 6.1: PCs connected through the powerline network The connected PCs automatically 2 choose an IP address with the same prefix as the USB IP. With an USB IP of fd2a:0:0:32de::1, the PC would choose and IP address starting with fd2a:0:0:32de:. In other words, the address would look like this: fd2a:0:0:32de:wwww:xxxx:yyyy:zzzz 1 Platypus emulates an RNDIS network card 2 Platypus sends out IPv6 Router Advertisements. These contain a Prefix Information section that inform the computer of the correct prefix. Page 16

21 Note: The automatically chosen IP address is usually very complex. For ease of use, you may optionally set your PC to any IP address with the same prefix, for example fd2a:0:0:32de::2. On Windows, the IP address is configured through the network settings like for any network interface. On Linux, the IP address is usually configured through Network Manager. 6.1 Routing from PC to PC On Windows computers, the routing table entries to reach all other PCs in the network are automatically 3 added. Linux must be first configured to accept the routing information that Platypus announces. Run the following command as root, then unplug and re-plug the USB connection to Platypus: echo 128 > /proc/sys/net/ipv6/conf/default/accept_ra_rt_info_max_plen To persist the setting across reboots, append this line to the file /etc/sysctl.conf: net.ipv6.conf.default.accept_ra_rt_info_max_plen = Ping Test To verify that end-to-end routing works correctly, ping computer A from the other one, computer B. The first step is to find out the IP address of computer A. Open a CMD window on A and enter ipconfig /all (figure IP address from ipconfig). Look for the block where Platypus Powerline Modem appears in the Description line. The IP address is listed as IPv6 Address. Write down the IP address and open a CMD window on B. On computer B, enter ping followed by the IP address of computer A. If everything is set up correctly, you will get a number of ping replies, proving that communication in both directions works. Alternatively, you can access the IP address through the Network Connections control panel (figure IP address from windows control panel). On Linux, the corresponding commands are \sbin\ifconfig and ping6. 3 Platypus sends IPv6 Router Information packets that inform the computer of available other computers. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 17

22 C:\>ipconfig /all Windows IP Configuration [...] Ethernet adapter Ethernet 2: Connection-specific DNS Suffix. : Description : Platypus Powerline Modem Physical Address : DA-F8-DB D8 DHCP Enabled : Yes Autoconfiguration Enabled.... : Yes IPv6 Address : fd2a::35db:d4bb:7f75:7fcd:a79(preferred) Temporary IPv6 Address : fd2a::35db:1de3:2039:6ce:5400(preferred) Link-local IPv6 Address..... : fe80::d4bb:7f75:7fcd:a79%15(preferred) Figure 6.2: IP address from ipconfig C:\>ping fd2a::35db:d4bb:7f75:7fcd:a79 Pinging fd2a::35db:d4bb:7f75:7fcd:a79 with 32 bytes of data: Reply from fd2a::35db:d4bb:7f75:7fcd:a79: time 760ms Reply from fd2a::35db:d4bb:7f75:7fcd:a79: time 531ms Reply from fd2a::35db:d4bb:7f75:7fcd:a79: time 450ms Reply from fd2a::35db:d4bb:7f75:7fcd:a79: time 327ms Figure 6.3: Pinging the other computer Page 18

23 1 2 3 Figure 6.4: IP address from windows control panel Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 19

24 CHAPTER SEVEN DMX DMX512 (digital multiplex, 512 channels) is the most common standard for controlling stage lighting. DMX uses RS-485 for data transmission. Platypus incorporates an RS-485 transceiver (also used for the serial bridge) and software support for controlling DMX devices. 7.1 Enable DMX Mode Platypus contains a single RS-485 that can be used for either the serial bridge or the DMX output. You choose DMX mode by writing dmx into the function configuration variable located in the rs485 folder. 7.2 Sending DMX Data DMX data is sent by writing to the special data variable in the dmx group. It expects a comma-separated list of decimal numbers. Each number represents a channel. The first number represents channel 1, the second channel 2 and so on. All channels that are not given are set to 0. Examples: 0 - set all channels to set channel 1 to 255, all higher channels to 0 0,255 - set channel 1 to 0, channel 2 to 255, all higher channels to 0 138,43,226 - for a RGB light that uses channels 1, 2 and 3, this sets the color to purple. Page 20

25 7.3 DMX Configuration Variables Reference Folder Variable Read/ Write Default Description rs485 function RW bridge Must be set to dmx to enable DMX mode rs485/dmx data RW 0 The channel value(s) as a comma-separated list of numbers from 0 to See Also Platypus Application Note AN50701 shows how to control a full-color DMX lightbar. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 21

26 CHAPTER EIGHT FIRMWARE UPDATE Updating the firmware is done via USB. The Platypus device needs to be put into firmware upgrade mode, which is initiated by pressing and holding the Recovery Button, then powering up the device. The location of the recovery button is shown below. It can be accessed using a long narrow tool like a 2mm screwdriver, a toothpick, or a paper clip. The button makes an audible click when pressed. Recovery Button Figure 8.1: Recovery button A DFU loader application is needed to perform the transfer. dfu-util ( ) is a free commandline utility that works on Windows, Mac OS X and Linux. Ready-to-use compiled versions for Windows are provided on the Page 22

27 dfu-util website. Major Linux distributions include dfu-util in their package repositories (Debian and Ubuntu: apt-get install dfu-util). 1. Unpower the Platypus device (disconnect both USB and power line) 2. Push and hold the recovery button 3. Connect USB. The device powers from USB and boots into ROM recovery. 4. Release the recovery button 5. Transfer the firmware via dfu-util: sudo dfu-util -v -d 0483:df11 -a 0 -s 0x D platypus-version.dfu 6. Unpower the device by disconnecting USB. Graphical tools for Windows are available as well, for example the DfuSe utility provided by STMicroelectronics, which are available for free download at The update process is identical apart from using the graphical DfuSe utility in step 6. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 23

28 CHAPTER NINE FACTORY RESET The factory reset sets all configuration variables to their default state. It does NOT revert the installed firmware. 1. Power up Platypus by connecting it to USB or the powerline 2. Press and hold the Recovery Button (see chapter Firmware Update) for five seconds 3. The System Status LED rapidly blinks yellow. Release the Recovery Button. Platypus will reboot as indicated by the System Status LED slowly blinking yellow. The process is complete and you can follow the steps in chapter Configuration to change settings from their default. Note: If the LEDs go dark after step 3, the Recovery Button was released too late and Platypus entered firmware upgrade mode. Power cycle the device for normal startup. Page 24

29 CHAPTER TEN ADVANCED CONFIGURATION 10.1 Manual Route Setup on Linux If the automatic configuration of IP addresses and routes fails or does not match your use case, you can configure both manually. This section describes the process on the Linux command line. 1. Assign an IPv6 address: sudo ip -6 addr add USBPREFIX::2/64 dev DEV 2. Add a route that points to the powerline network: sudo ip -6 route add PLCPREFIX::/64 via USBPREFIX::1 [Optional] Assuming a second PC is connected to another remote Platypus a route to this PC can be added: sudo ip -6 route add REMOTE_USBPREFIX::/64 via USBPREFIX::1 Example with prefixes as shown in Fig. 2.1: sudo ip -6 addr add fd79:db0f:5bc3:2::2/64 dev <dev> sudo ip -6 route add fd79:db0f:5bc3:1::/64 via fd79:db0f:5bc3:2::1 sudo ip -6 route add fd79:db0f:5bc3:3::/64 via fd79:db0f:5bc3:2::1 Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 25

30 CHAPTER ELEVEN MECHANICAL DIMENSIONS Figure 11.1: Mechanical drawing Page 26

31 CHAPTER TWELVE CHANGELOG Revision Changes Simplify serial bridge buffering scheme; Add Mechanical Dimensions chapter v1.3 Correct minimum baud rate value (600, not 110) v1.2 Detail serial bridge buffer modes; Add find-me function to Configuration Variables Reference section; Move Wire Terminal Reference and GPIOs chapters to the front v1.1 Add instructions for Windows networking v1.0 Describe integrated RS485 transceiver v0.2 Add serial bridge description v0.1 Add firmware update description v0 Initial version Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 27

32 CHAPTER THIRTEEN OPEN SOURCE LICENSES Platypus incorporates open source software. The licenses are reproduced below microcoap Copyright (c) 2013 Toby Jaffey Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the Software ), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUD- ING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PUR- POSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTH- ERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEAL- INGS IN THE SOFTWARE RIOT OS GNU Lesser General Public License Version 2.1, February 1999 Copyright (c) 1991, 1999 Free Software Foundation, Inc 51 Franklin Street, Fifth Floor, Boston, MA USA Page 28

33 Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. This is the first released version of the Lesser GPL. It also counts as the successor of the GNU Library Public License, version 2, hence the version number 2.1. Preamble The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public Licenses are intended to guarantee your freedom to share and change free software to make sure the software is free for all its users. This license, the Lesser General Public License, applies to some specially designated software packages typically libraries of the Free Software Foundation and other authors who decide to use it. You can use it too, but we suggest you first think carefully about whether this license or the ordinary General Public License is the better strategy to use in any particular case, based on the explanations below. When we speak of free software, we are referring to freedom of use, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish); that you receive source code or can get it if you want it; that you can change the software and use pieces of it in new free programs; and that you are informed that you can do these things. To protect your rights, we need to make restrictions that forbid distributors to deny you these rights or to ask you to surrender these rights. These restrictions translate to certain responsibilities for you if you distribute copies of the library or if you modify it. For example, if you distribute copies of the library, whether gratis or for a fee, you must give the recipients all the rights that we gave you. You must make sure that they, too, receive or can get the source code. If you link other code with the library, you must provide complete object files to the recipients, so that they can relink them with the library after making changes to the library and recompiling it. And you must show them these terms so they know their rights. We protect your rights with a two-step method: (1) we copyright the library, and (2) we offer you this license, which gives you legal permission to copy, distribute and/or modify the library. To protect each distributor, we want to make it very clear that there is no warranty for the free library. Also, if the library is modified by someone else and passed on, the recipients should know that what they have is not the original version, so that the original author s reputation will not be affected by problems that might be introduced by others. Finally, software patents pose a constant threat to the existence of any free program. We wish to make sure that a company cannot effectively restrict the users of a free program by obtaining a restrictive license from a patent holder. Therefore, we insist that any patent license obtained for a version of the library must be consistent with the full freedom of use specified in this license. Most GNU software, including some libraries, is covered by the ordinary GNU General Public License. This license, the GNU Lesser General Public License, applies to certain designated libraries, and is quite different from the ordinary General Public License. We use this license for certain libraries in order to permit linking those libraries into non-free programs. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 29

34 When a program is linked with a library, whether statically or using a shared library, the combination of the two is legally speaking a combined work, a derivative of the original library. The ordinary General Public License therefore permits such linking only if the entire combination fits its criteria of freedom. The Lesser General Public License permits more lax criteria for linking other code with the library. We call this license the Lesser General Public License because it does Less to protect the user s freedom than the ordinary General Public License. It also provides other free software developers Less of an advantage over competing non-free programs. These disadvantages are the reason we use the ordinary General Public License for many libraries. However, the Lesser license provides advantages in certain special circumstances. For example, on rare occasions, there may be a special need to encourage the widest possible use of a certain library, so that it becomes a de-facto standard. To achieve this, non-free programs must be allowed to use the library. A more frequent case is that a free library does the same job as widely used non-free libraries. In this case, there is little to gain by limiting the free library to free software only, so we use the Lesser General Public License. In other cases, permission to use a particular library in non-free programs enables a greater number of people to use a large body of free software. For example, permission to use the GNU C Library in non-free programs enables many more people to use the whole GNU operating system, as well as its variant, the GNU/Linux operating system. Although the Lesser General Public License is Less protective of the users freedom, it does ensure that the user of a program that is linked with the Library has the freedom and the wherewithal to run that program using a modified version of the Library. The precise terms and conditions for copying, distribution and modification follow. Pay close attention to the difference between a work based on the library and a work that uses the library. The former contains code derived from the library, whereas the latter must be combined with the library in order to run. TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 0. This License Agreement applies to any software library or other program which contains a notice placed by the copyright holder or other authorized party saying it may be distributed under the terms of this Lesser General Public License (also called this License ). Each licensee is addressed as you. A library means a collection of software functions and/or data prepared so as to be conveniently linked with application programs (which use some of those functions and data) to form executables. The Library, below, refers to any such software library or work which has been distributed under these terms. A work based on the Library means either the Library or any derivative work under copyright law: that is to say, a work containing the Library or a portion of it, either verbatim or with modifications and/or translated straightforwardly into another language. (Hereinafter, translation is included without limitation in the term modification.) Source code for a work means the preferred form of the work for making modifications to it. For a library, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the library. Page 30

35 Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running a program using the Library is not restricted, and output from such a program is covered only if its contents constitute a work based on the Library (independent of the use of the Library in a tool for writing it). Whether that is true depends on what the Library does and what the program that uses the Library does. 1. You may copy and distribute verbatim copies of the Library s complete source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and distribute a copy of this License along with the Library. You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee. 2. You may modify your copy or copies of the Library or any portion of it, thus forming a work based on the Library, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions: a) The modified work must itself be a software library. b) You must cause the files modified to carry prominent notices stating that you changed the files and the date of any change. c) You must cause the whole of the work to be licensed at no charge to all third parties under the terms of this License. d) If a facility in the modified Library refers to a function or a table of data to be supplied by an application program that uses the facility, other than as an argument passed when the facility is invoked, then you must make a good faith effort to ensure that, in the event an application does not supply such function or table, the facility still operates, and performs whatever part of its purpose remains meaningful. (For example, a function in a library to compute square roots has a purpose that is entirely well-defined independent of the application. Therefore, Subsection 2d requires that any application-supplied function or table used by this function must be optional: if the application does not supply it, the square root function must still compute square roots.) These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Library, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Library, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it. Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Library. In addition, mere aggregation of another work not based on the Library with the Library (or with a work based on the Library) on a volume of a storage or distribution medium does not bring the other work under the scope of this License. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 31

36 3. You may opt to apply the terms of the ordinary GNU General Public License instead of this License to a given copy of the Library. To do this, you must alter all the notices that refer to this License, so that they refer to the ordinary GNU General Public License, version 2, instead of to this License. (If a newer version than version 2 of the ordinary GNU General Public License has appeared, then you can specify that version instead if you wish.) Do not make any other change in these notices. Once this change is made in a given copy, it is irreversible for that copy, so the ordinary GNU General Public License applies to all subsequent copies and derivative works made from that copy. This option is useful when you wish to copy part of the code of the Library into a program that is not a library. 4. You may copy and distribute the Library (or a portion or derivative of it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you accompany it with the complete corresponding machinereadable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange. If distribution of object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place satisfies the requirement to distribute the source code, even though third parties are not compelled to copy the source along with the object code. 5. A program that contains no derivative of any portion of the Library, but is designed to work with the Library by being compiled or linked with it, is called a work that uses the Library. Such a work, in isolation, is not a derivative work of the Library, and therefore falls outside the scope of this License. However, linking a work that uses the Library with the Library creates an executable that is a derivative of the Library (because it contains portions of the Library), rather than a work that uses the library. The executable is therefore covered by this License. Section 6 states terms for distribution of such executables. When a work that uses the Library uses material from a header file that is part of the Library, the object code for the work may be a derivative work of the Library even though the source code is not. Whether this is true is especially significant if the work can be linked without the Library, or if the work is itself a library. The threshold for this to be true is not precisely defined by law. If such an object file uses only numerical parameters, data structure layouts and accessors, and small macros and small inline functions (ten lines or less in length), then the use of the object file is unrestricted, regardless of whether it is legally a derivative work. (Executables containing this object code plus portions of the Library will still fall under Section 6.) Otherwise, if the work is a derivative of the Library, you may distribute the object code for the work under the terms of Section 6. Any executables containing that work also fall under Section 6, whether or not they are linked directly with the Library itself. 6. As an exception to the Sections above, you may also combine or link a work that uses the Library with the Library to produce a work containing portions of the Library, and distribute that work under terms of your choice, provided that the terms permit modification of the work for the customer s own use and reverse engineering for debugging such modifications. Page 32

37 You must give prominent notice with each copy of the work that the Library is used in it and that the Library and its use are covered by this License. You must supply a copy of this License. If the work during execution displays copyright notices, you must include the copyright notice for the Library among them, as well as a reference directing the user to the copy of this License. Also, you must do one of these things: a) Accompany the work with the complete corresponding machine-readable source code for the Library including whatever changes were used in the work (which must be distributed under Sections 1 and 2 above); and, if the work is an executable linked with the Library, with the complete machine-readable work that uses the Library, as object code and/or source code, so that the user can modify the Library and then relink to produce a modified executable containing the modified Library. (It is understood that the user who changes the contents of definitions files in the Library will not necessarily be able to recompile the application to use the modified definitions.) b) Use a suitable shared library mechanism for linking with the Library. A suitable mechanism is one that (1) uses at run time a copy of the library already present on the user s computer system, rather than copying library functions into the executable, and (2) will operate properly with a modified version of the library, if the user installs one, as long as the modified version is interface-compatible with the version that the work was made with. c) Accompany the work with a written offer, valid for at least three years, to give the same user the materials specified in Subsection 6a, above, for a charge no more than the cost of performing this distribution. d) If distribution of the work is made by offering access to copy from a designated place, offer equivalent access to copy the above specified materials from the same place. e) Verify that the user has already received a copy of these materials or that you have already sent this user a copy. For an executable, the required form of the work that uses the Library must include any data and utility programs needed for reproducing the executable from it. However, as a special exception, the materials to be distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable. It may happen that this requirement contradicts the license restrictions of other proprietary libraries that do not normally accompany the operating system. Such a contradiction means you cannot use both them and the Library together in an executable that you distribute. 7. You may place library facilities that are a work based on the Library side-by-side in a single library together with other library facilities not covered by this License, and distribute such a combined library, provided that the separate distribution of the work based on the Library and of the other library facilities is otherwise permitted, and provided that you do these two things: a) Accompany the combined library with a copy of the same work based on the Library, uncombined with any other library facilities. This must be distributed under the terms of the Sections above. b) Give prominent notice with the combined library of the fact that part of it is a work based on the Library, and explaining where to find the accompanying uncombined form of the same work. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 33

38 8. You may not copy, modify, sublicense, link with, or distribute the Library except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, link with, or distribute the Library is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance. 9. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Library or its derivative works. These actions are prohibited by law if you do not accept this License. Therefore, by modifying or distributing the Library (or any work based on the Library), you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or modifying the Library or works based on it. 10. Each time you redistribute the Library (or any work based on the Library), the recipient automatically receives a license from the original licensor to copy, distribute, link with or modify the Library subject to these terms and conditions. You may not impose any further restrictions on the recipients exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties with this License. 11. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Library at all. For example, if a patent license would not permit royalty-free redistribution of the Library by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Library. If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply, and the section as a whole is intended to apply in other circumstances. It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice. This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License. 12. If the distribution and/or use of the Library is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Library under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License. 13. The Free Software Foundation may publish revised and/or new versions of the Lesser General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Page 34

39 Each version is given a distinguishing version number. If the Library specifies a version number of this License which applies to it and any later version, you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Library does not specify a license version number, you may choose any version ever published by the Free Software Foundation. 14. If you wish to incorporate parts of the Library into other free programs whose distribution conditions are incompatible with these, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally. NO WARRANTY 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE LIBRARY AS IS WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAR- RANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPY- RIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE LIBRARY AS PER- MITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Platypus User Manual Theobroma Systems Design und Consulting GmbH Page 35