SensRcore Messaging and Usage

Transcription

1 SensRcore Messaging and Usage D Rev1.4 Dynastream Innovations Inc. July 6, 2007 P F

2 2 of 17 Copyright Information and Usage Notice This information disclosed herein is the exclusive property of Dynastream Innovations Inc. No part of this publication may be reproduced or transmitted in any form or by any means including electronic storage, reproduction, execution or transmission without the prior written consent of Dynastream Innovations Inc. The recipient of this document by its retention and use agrees to respect the copyright of the information contained herein. The information contained in this document is subject to change without notice and should not be construed as a commitment by Dynastream Innovations Inc. unless such commitment is expressly given in a covering document. The Dynastream Innovations Inc. ANT Products described by the information in this document are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Dynastream product could create a situation where personal injury or death may occur. If you use the Products for such unintended and unauthorized applications, you do so at your own risk and you shall indemnify and hold Dynastream and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Dynastream was negligent regarding the design or manufacture of the Product Dynastream Innovations Inc. All Rights Reserved.

3 3 of 17 TABLE OF CONTENTS 1 INTRODUCTION NVM ORGANIZATION NVM SECTORS NVM FLAGS NVM DATA COMMANDS NVM MEMORY MAP NVM COMMANDS SERIAL NVM MESSAGES NVM_Write (0x56) NVM_Clear (0x57) NVM_Dump (0x57) NVM_SetDefaultSector (0x57) NVM_EndSector (0x57) NVM_Lock (0x57) SENSRCORE CONFIGURATION COMMANDS Set ANT Channel Input Mask (0x90) Set ANT Channel Data Source (0x91) Read Pins for Sector (0x92) Timer Period Select (0x93) A/D Settings (0x94) Slave Shared Channel Address Configuration (0x95) ANT SENSRCORE GLOBAL DATA MESSAGE FORMAT ANT SENSRCORE GLOBAL DATA TYPES DIGITAL DATA GLOBAL DATA IDENTIFICATION 0X ANALOG DATA GLOBAL DATA IDENTIFICATION 0X FREQUENCY COUNTER DATA GLOBAL IDENTIFICATION 0X

4 4 of 17 1 Introduction A standard ANT chipset or module is a versatile tool to facilitate ultra low power, low cost wireless communication. ANT devices can easily be configured to setup wireless communication channels using a simple host microcontroller. SensRcore technology now goes one step further allowing an ANT device to further be configured as a sensor device directly, with A/D inputs, and/or digital inputs and outputs therefore eliminating the need for a host microcontroller at all. This document describes the details and use of ANT SensRcore including NVM organization, writing and reading of NVM, SensRcore configuration commands, and the format of the ANT SensRcore messages generated by the available SensRcore modes.

5 5 of 17 2 NVM Organization The data contained in the NVM is accessed by the ANT Module on startup when the ANT module is placed in SensRcore mode, which is achieved by tying the IOSEL pin low. When the IOSEL pin is tied high, the serial interface is enabled, allowing the NVM to be written. During the startup sequence of SensRcore mode (IOSEL tied low), the module reads commands from its NVM and executes them based on which sector is selected. The commands are processed by the module s serial command interpreter the same way a normal serial message would be. In this way, the module can be placed in predetermined configurations without receiving serial messages from a host controller. Commands are read out one at a time and processed in order. In order for the data to be read and commands to be executed successfully, the NVM data is organized in a specific fashion using Sectors, Flags, and specific data formats to achieve this requirement. 2.1 NVM Sectors The NVM is organized into sectors. These sectors exist in order to provide a user with the ability to store several different configurations or command sequences for selection at operation time. Sectors are numbered sequentially based on the number of End of Sector flags that have been read to that point. Sector 0 is a special sector that is always executed, either alone or in combination with another selected sector. The other sectors that are present can be selected either by a written command, or by externally driven IO lines. 2.2 NVM Flags The NVM is organized based on sectors and these sectors are achieved using three separate flags: Start of NVM, End of NVM, and End of Sector. Start of NVM (0xEE) This flag should appear as the very first byte in the NVM. If it is not the first byte, no other data will be read out of the NVM. End of NVM (0xEF) This flag indicate an end of the useful data on the NVM. An NVM format or partial format can be achieved by overwriting the byte at a specific location with the End of NVM flag. End of Sector (0xED) The End of Sector flag denotes the end of a sector on the NVM. 2.3 NVM Data Commands NVM data commands are the actual command information stored in the NVM. The commands are stored with an initial byte indicating the size of the command, followed by the actual command data bytes. The data bytes for a command are identical to those found in the serial messages that can be passed to the module. These messages are detailed in document D ANT Message Protocol and Usage. The data includes the Message ID and the appropriate data for that message. This format repeats for however many commands exist in a given sector of the NVM. 2.4 NVM Memory Map Below is a sample memory map of the NVM. 0xEE (NVM start), Default Sector Num, Command Size, Command Msg ID, Command Data1, Command Data2, Command DataX Command Size, Command Msg ID, Command Data1, Command Data2, Command DataX

6 6 of 17 0xED (end sector) Command Size, Command Msg ID, Command Data1, Command Data2, Command DataX Command Size, Command Msg ID, Command Data1, Command Data2, Command DataX 0xED (end sector) 0xEF (NVM end)

7 7 of 17 3 NVM Commands The following section details the serial commands that can be sent to the ANT Module to access and program the module s NVM. There are two main messages, NVM_DATA and NVM_CMD, with several sub messages for NVM_CMD that allow the NVM to be properly formatted and loaded with command information. 3.1 Serial NVM Messages NVM_Write (0x56) void ANT_NVM_Write(UCHAR ucsize, UCHAR *puccmd); Parameters Type Range Description Size UCHAR The size of the command, which is the number of data bytes + 1 for the Cmd ID Cmd ID UCHAR The ID of the command to be programmed into NVM Command Data 0 UCHAR Command byte 0 Command Data 1 UCHAR Command byte 1 Command Data 2 UCHAR Command byte 2 Command Data 3 UCHAR Command byte 3 Command Data 4 UCHAR Command byte 4 Command Data 5 UCHAR Command byte 5 Command Data 6 UCHAR Command byte 6 Command Data 7 UCHAR Command byte 7 Command Data 8 UCHAR Command byte 8 UCHAR auccommand = {0x42, 0x00, 0x10, 0x00}; // sample Network Key ANT_NVM_Write(4, auccommand); // write auccommand, an assign channel command that assigns // channel 0 as a Master Channel This message writes a command into NVM. These commands are then read out and executed in order when the module starts up in SensRcore mode. This command can be of variable length and requires only as many data bytes as are required by the command that is being programmed into NVM NVM_Clear (0x57) void ANT_NVM_Clear(); Parameters Type Range Default Description Cmd Number UCHAR 0 0 Specifies the clear command ANT_NVM_Clear(); // clears the NVM This message is sent to the module to clear the NVM. This command must be performed before commands are written into the NVM using NVM_Write NVM_Dump (0x57) void ANT_NVM_Dump();

8 8 of 17 Parameters Type Range Range Description Cmd Number UCHAR 1 1 Specifies the dump command /*****************************************************/ ANT_NVM_Dump(); // NVM_Write commands will be sent to the Response func and it will end with a message of the format // [57][00][04][xx] where [xx] is the number of messages that have been read out This message is sent to the module to dump the contents of the NVM. It causes the part to send NVM_Write commands to the Host with the data commands that have been sent in, unless the NVM has been locked from reading (3.1.6 below). It also will send out NVM_EndSector commands to denote the end of a sector and an NVM_DefaultSector command with the stored default sector. Finally, an NVM_Cmd with a command number of 0x04 will be sent to signify the end of the Dump and denote how many commands were sent NVM_SetDefaultSector (0x57) void ANT_NVM_SetDefaultSector(UCHAR ucdefaultsector); Parameters Type Range Default Description Cmd Number UCHAR 2 2 Specifies the set default sector command Default Sector UCHAR The default sector to be set ANT_NVM_SetDefaultSector(3); // set the Default Sector to 3 This message is sent to the module to set the default sector. This sector is what will be executed after sector 0 is complete. Only one sector besides sector 0 is ever executed on startup. The default sector is not used if the Read Pins for Sector command is present in sector 0, or the default sector is set to 0, which is the default NVM_EndSector (0x57) void ANT_NVM_EndSector(); Parameters Type Range Default Description Cmd Number UCHAR 3 3 Specifies the end sector command ANT_NVM_EndSector(); // puts a sector break in the NVM This message is sent to the module to put a sector break in the NVM image. Sector breaks are used to separate optional blocks of configuration commands. The first sector (sector 0) is always run on startup so a typical image would feature generic commands in this sector. By adding more sectors, different devices using the same NVM image can be made to have different configurations using separate sectors that may be selected with the DevSel pins NVM_Lock (0x57) void ANT_NVM_Lock(); Parameters Type Range Default Description Cmd Number UCHAR 5 5 Specifies the lock command ANT_NVM_Lock(); // Locks the NVM

9 9 of 17 This message is sent to the module to lock the NVM. This command prevents the contents of the NVM from being dumped in order to provide security for NVM images. The only way to Dump the contents after an NVM_Lock command is to clear the NVM, and rewrite it.

10 10 of 17 4 SensRcore Configuration Commands The following messages are used to configure a SensRcore device. Care should be taken to configure all appropriate pieces of information for an ANT channel before opening it. All configuration commands return a response to indicate their success or failure to be written into NVM, therefore a simple state machine can be setup for configuration. Configuration would advance state only when a RESPONSE_NO_ERROR is received for the current command and would re-send upon failure Set ANT Channel Input Mask (0x90) Parameters Type Range Description ANT Channel Number UCHAR 0-MAX_CHAN - 1 ANT channel number Input Type UCHAR x00 No input (default) 0x01 Digital Data 1 UCHAR Input Type 0 Reserved Input Type 1 IO pin mask of enabled outputs Data 2 UCHAR Input Type 0 Reserved Input Type 1 Value 1 indicates Output Crossover Mode Enabled, so incoming digital data is nibble reversed (most significant 4 bits and least significant 4 bits are swapped). Data 3 UCHAR Input Type 0 Reserved Input Type 1 Default state of enabled outputs // Example usage [90][00][01][03][01][00] //Allows incoming digital messages to affect pins IO0 and IO1. Since // crossover mode is enabled, a value of 0x30 in the incoming RF // message would set both outputs. Outputs are low on startup. This message is programmed into the NVM configuration to configure the ANT SensRcore module to process receive data. Currently, only digital data can be processed. The IO mask of the pins that can be affected by incoming ANT messages are configured with this message as well as whether the ANT message data is Crossed Over. When crossover is enabled, incoming digital data messages have their nibbles reversed, so the data in the top nibble is applied to the pins represented in the bottom nibble and vice versa, which can be used when two IO sensrcore devices are directly interacting. The initial state of the outputs can be set either high or low.

11 11 of Set ANT Channel Data Source (0x91) Parameters Type Range Description ANT Channel Number Data Channel Number UCHAR UCHAR 0..MAX_CHAN MAX_DATA_ CHAN-1 Data Type UCHAR As specified 0x40 Digital Input 0x41 Analog Input 0x42 Counter Input Pin Enable Mask/Pin Number Message Ratio Message Ratio Offset The ANT channel number to be associated with the assigned data channel number. The Data Channel number to be used as a data source for a particular ANT channel. More than one Data Channel may be assigned to a single ANT channel, but each Data Channel may only be assigned once to a single ANT channel. UCHAR Specifies the pins to be associated with this channel. Only one analog or counter input can be associated with a channel, but all Digital input pins can be assigned to a single channel if desired. Digital inputs use a pin mask to represent the 8 possible inputs. Analog and Counter inputs use number values to represent an individual pin (2 = pin AIO2). Analog has two special pins for use of the internal temperature and battery voltage sources, these are accessed using 0xFF (Battery) and 0xFE (Temperature) Digital input selection XXXXXXXX - Input byte mask represents digital inputs 0-7 Analog input selection 0x00 AIO0 0x01 AIO1 0x02 AIO2 0x03 AIO3 0x04 AIO4 0xFE Temperature 0xFF Input Voltage Counter input selection 0x00 Counter0 (AIO0) 0x01 Counter1 (AI01) 0x02 Counter2 (AIO2) 0x03 Counter3 (AIO3) 0x04 Counter4 (AIO4) UCHAR Number of ANT messages between each data message sent from this data source (e.g. Message Ratio = 2, would have this data take every second message on the ANT RF channel, 4 would have it take every fourth) UCHAR Allows spacing between messages to distribute messages within a 256 message cycle with minimal conflicts. [91][00][00][41][01][02][00] // Assign data channel 0 as A/D input from pin AIO1, being sent over ANT // Channel 0 on every second message interleaved with data channel 1 below [91][00][01][42][03][02][01] // Assign data channel 1 as counter input from pin AIO3, being sent over ANT // Channel 0 on every second message interleaved with data channel 0 above This message is programmed into NVM to assign a data channel to an ANT channel. Data Channel types determine the data source type, the data source physical pin, and the rate at which this data is sent over the specified ANT channel. Multiple data channels can be assigned to a single ANT channel and data from multiple data channels can be interleaved in a periodic way using the Message Ratio and Message Ratio Offset parameters Read Pins for Sector (0x92) Parameters Type Bit Range Range Description Filler UCHAR - 0 Filler Byte [92][00] This message is programmed into NVM to cause a device to determine its default sector (the sector to be run after sector 0) from the DevSel pins. This command must be placed in Sector 0 to be recognized.

12 12 of Timer Period Select (0x93) Parameters Type Range Default Description Filler UCHAR 0 0 Filler Byte Timer Period USHORT (little endian) (1Hz) [93][00][00][20] //Set sample timer to 4 Hz The timer period in seconds * Maximum messaging period is ~2 seconds. This message configures the base timer period for all data channels I.E. the fundamental A/D sample rate: Timer Period = Timer Period Time (s) * E.g.: To sample at 4Hz, set the Timer Period to 32768/4 = Note: The minimum acceptable message period is difficult to specify as it is system dependent and depends on the number of configured channels and their use. Caution should be used to appropriately test the system when high data rates are used, especially in combination with multiple channels. It is of critical importance that the timer period be defined in a manner consistent with the needs of the application. Some issues to consider are: 1. A smaller timer period increases the sample rate and thus increases system power consumption (see respective ANT product datasheet for details). 2. A slower timer period may not allow sufficient resolution or responsiveness A/D Settings (0x94) Parameters Type Range Description Reserved UCHAR 0 Reserved byte Data Channel Number UCHAR 0..MAX_DATA_ CHAN-1 The data channel number. Must correspond to an assigned Analog data channel. A/D Configuration UCHAR Specified Bit 0-2: Reference source, available values are 0 (Vcc reference) and 1 (internal reference) Bit V Internal Reference (Bit Set), 1.5 V Internal Reference (Bit Cleared) Bit 4: Clear Min/Max on ANT RF Channel Message Period Bit 5: Hardware timer sample (only on data channel 0) Bit 6-7: Reserved Timer Ratio UCHAR Number of timer periods between samples Filter Parameter N UCHAR Value of N in Filter Equation Reserved USHORT 0 Reserved bytes [94][00][09][02][08][00][00] Use 2.5 V internal reference, sample every 2 nd timer period, N = 8 This message is programmed into the NVM to configure the A/D sample settings for a specific A/D data channel. The A/D Configuration byte is defined as follows: Bit 0-3 specifies the reference source for the A/D, however the reference voltage is fixed for Temperature and Battery A/D samples to use the 1.5V internal source. Bit 4 sets the minimum and maximum A/D sample values to be cleared on every message transmission or not. Bit 5 enables the A/D sampling to be hardware timed instead of software sampled, which reduces sample timing dither, which can be important when sampling rapidly changing analog sources. The disadvantage of hardware sampling which is only available to Data Channel 0 is that it requires the A/D reference to be on continuously instead of the default of only when an A/D sample is being taken. Enabling hardware sampling therefore increases the average power consumption. The Timer Ratio is used to reduce the sample rate from the selected fundamental timer rate that was selected with the Timer Select Period message above, to meet the required sampling rate for the particular A/D signal. For example a value of 1 means that an A/D pin will be sampled on every fundamental Timer Period and a value of 2 means that an A/D pin will be sampled on every 2 nd fundamental Timer Period. The Filter Parameter N sets the parameter for the filter that is implemented on every A/D or Temperature channel. This filter is present to provide some initial data smoothing if desired. The filter is of the form:

13 13 of 17 Output(x) = (Output(x-1)*(N-1) + Sample)/N A value of N = 1 will provide no filtering Slave Shared Channel Address Configuration (0x95) Parameters Type Range Default Description ANT Channel Number Shared Address Mode Shared Address LSB Shared Address MSB UCHAR 0..MAX_CHAN-1 - The channel to be unassigned. UCHAR Manual Shared Address 1 Serial Number Shared Address 2 Auto Shared Channel Address Acquisition UCHAR Valid only for Manual Shared Address Mode UCHAR Valid only for Manual Shared Address Mode // Example [95][00][00][03][00] // Manually set shared address on ANT Channel 0 to 3 [95][00][01] // Set shared address for ANT channel 0 to the two least significant bytes of the serial number [95][00][02] // Use automatic shared channel address acquisition for channel 0 This message is programmed into the NVM in order to enable the setting of the shared address for a shared channel slave. The shared address number can be assigned manually by the user, set to be the internal serial number of the device, or set to automatically be acquired from the shared master.

14 14 of 17 5 ANT SensRcore Message Format ANT SensRcore mode can be configured to send many different types of data however there is a global format that applies to all SensRcore data formats. Some formatting information is now provided within the Transmission Type field of the device ID (see D ANT Message Protocol and Usage document for further description of the Transmission Type and Identification fields) as follows: Transmission Type Definition Transmission Type Value Bit Definition Description 0-1 0x01 No Shared Address 0-1 0x02 1 Byte Shared Address 0-1 0x03 2 Byte Shared Address 2 0x04 Identification Byte Flag. Indicates that the byte immediately following the defined shared address field as described by Bits 0 and 1 above is a Identification Byte. The Identification byte is defined in section 0 below 3-7 Undefined Reserved for future use. Initialized to 0. Example 1: Transmission Type: xxxxx001 - Broadcast messaging (no shared address field) - No Identification Byte ANT Message 8 Byte Data Payload Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 User Data 0 User Data 1 User Data 2 User Data 3 User Data 4 User Data 5 User Data 6 User Data 7 Example 2: Transmission Type: xxxxx101 - Broadcast messaging (no shared address field) - Identification Byte present ANT Message 8 Byte Data Payload Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Identification Byte Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Example 3: Transmission Type: xxxxx111-2 Byte Shared Address field - Identification Byte present ANT Message 8 Byte Data Payload Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 Data 6 Data 7 Shared Address (LSB) Shared Address (MSB) Identification Byte Data 3 Data 4 Data 5 Data 6 Data 7

15 15 of 17 6 ANT SensRcore Types ANT SensRcore Mode has defined several globally available data types for any ANT device to make use of. The currently defined Types are: Digital data, Analog data, and Frequency Counter data. Each Type has a defined data payload associated with it. 6.1 Digital Data Identification 0x40 The Digital Data message reports the polled state of digital input signals. On a SensRcore device each bit of the Input Pin State byte corresponds to a matching I/O signal pin (i.e. Bit 0 -> AIO0). The Input Pin Mask byte indicates which inputs are enabled or valid for the data source. ANT Message Payload Byte Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Parameters Type Range Description Reserved 0 UCHAR N/A Reserved (Initialized to 0) Reserved 1 UCHAR N/A Reserved (Initialized to 0) Reserved 2 UCHAR N/A Reserved (Initialized to 0) Input Pin Mask UCHAR Indicates which pins are valid for this channel Input Pin State UCHAR Indicates the state of the I/O pins of the device // Example [00][00][00][0F][05] // This indicates that channel s valid inputs are AIO0 AIO3 // and that AIO0 and AIO2 are high 6.2 Analog Data Identification 0x41 The Analog Data message reports polled filtered or unfiltered analog data. Also reported is the analog signal source, and the minimum and maximum values either over the last period, or since initialization.

16 16 of 17 ANT Message Payload Byte Byte 3 Parameters Type Range Description Analog Signal Source UCHAR Indicates signal source: 0-4 represents pins AIO0-AIO4 special values are: 0xFE -> Temperature Temp(C)=(V-0.986)/ Byte 4 Byte 5 Byte 6 Byte 7 0xFF -> Battery Voltage Max (8-bit) UCHAR most significant bits of the maximum recorded analog level, either in the past message period, or since initialization Temperature is represented differently as a value equal to Temperature rounded to the nearest degree Min (8-bit) UCHAR most significant bits of the minimum recorded analog level, either in the past message period, or since initialization Temperature is represented differently as a value equal to Temperature rounded to the nearest degree Measured A/D Data USHORT The measured A/D data from the analog signal. This data is 16-bit sampled at a user defined rate and optionally filtered. // Example [01][B0][A2][C0][A9] // This indicates an analog signal originating from AI01, with a current // measurement of 0xA9C0, a minimum measured value of 0xA2xx, // and a maximum measured value of 0xB0xx Temperature is represented differently as a value equal to Temperature*100 Sample Voltage Conversion: ADC Val = 0xA9C0 V = ADC Val/Max_16Bit*VRef Max_16Bit = 0xFFFF Assuming VRef = 1.5V V = 0xA9C0/0xFFFF*1.5V = V 6.3 Frequency Counter Data Identification 0x42 The Frequency Counter Data message gives a frequency representation of a frequently changing digital signal. IE a reed switch pickup on a bike wheel. A SensRcore Frequency Counter will count the number of low to high edge transitions on a given digital input signal and time-stamp each edge measurement. The timestamp marks a position in a 64 second rollover counter. From the differential of values in the timestamp and count fields between messages, an instantaneous frequency can be determined. The maximum measurable input frequency for a SensRcore device is 1 khz.

17 17 of 17 ANT Message Payload Byte Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Parameters Type Range Description Frequency Counter Signal Pin Cumulative Count Time Stamp Signal Edge Cumulative Rollover Counter // Example [00][B0][A9][05][00] [00][C0][A9][06][00] // This indicates a frequency counter on pin AIO0, where // the instantaneous frequency is 64 Hz UCHAR Indicates the frequency counter signal input pin AIOx where x is a value between 0 and 4. USHORT A relative time value that rolls over every 64 seconds. This can be used to estimate frequency along with the cumulative count. This time stamp refers to the time of the last detected edge. USHORT The cumulative number of rising edges detected on the associated input pin. Rolls over at 0xFFFF. Sample Calculation: Time2 = 0xA9C0, Time1 = 0xA9B0 T = Time2 Time1 = 0x10 Count = 0x0006 0x0005 = 0x0001 F = 1/(( T*Conversion_to_s)/ Count) Conversion_to_s = 64s/0x /(0x10*(64s/0x10000)) = 1/(1/64 s) = 64 Hz The host controller receiving the data can use the cumulative count and its own measure of elapsed time based on messages to track frequencies slower than 1/16 Hz.