2 in 1. EasyAVR4 User s Manual AVR. MikroElektronika. Software and Hardware solutions for Embedded World

Transcription

1 SOFTWARE AND HARDWARE SOLUTIONS FOR THE EMBEDDED WORLD - Books - Compilers User s Manual 2 in IN-CIRCUIT PROGRAMMER ATMEL AVR DEVELOPMENT BOARD With useful implemented peripherals, plentiful practical code examples and a broad set of additional add-on boards (Serial Ethernet, Compact Flash, MMC/SD, ADC, DAC, CAN, RTC, RS-85, etc.), development boards make fast and reliable that can satisfy the needs of experienced engineers and beginners alike. Software and Hardware solutions for Embedded World

2 User s Manual Second edition December 2006 No part of this manual, including the product and software described in it, may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language in any form or by any means, except documentation kept buy the purchaser for backup purposes, without the express written permission of company. Product warranty or service will not be extended if the product is repaired, modified or altered, unless such repair, modification or alteration is authorized in writing by. MIKROELEKTRONIKA PROVIDE THIS MANUAL AS IS WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OR CONDITIONS OF MERCHANTABILITY OR FITNESS FOR A PARTIC- ULAR PUROSE. IN NO EVENT SHALL MIKROELEKTRONIKA, ITS DIRECTORS, OFFICERS, EMPLOY- EES OR DISTRIBUTORS BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES(INCLUDING DAMAGES FOR LOSS OF PROFITS, LOSS OF BUSINESS, LOSS OF USE OR DATA, INTERRUPTION OF BUSINESS AND THE LIKE) EVEN IF MIKROELEKTRONIKA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES ARISING FROM ANY DEFECT OR ERROR IN THIS MANUAL OR PRODUCT. SPECIFICATION AND INFORMATION CONTAINED IN THIS MANUAL ARE FURNISHED FOR INTERNATIONAL USE ONLY, AND ARE SUBJECT TO CHANGE AT ANY TIME WITH- OUT NOTICE, AND SHOULD BE CONSTRUED AS A COMMITMENT BY MIKROELEKTRONIKA assumes no responsibility or liability for any errors or inaccuracies that may appear in this manual, including the product and software described in it. Product and corporate names appearing in this manual may or may not be registered trademarks or copyrights of their respective companies, and are used only for identification or explanation and to the owners benefit, without intent to infringe. 2

3 User s Manual CONTENTS CONNECTING THE SYSTEM INTRODUCTION 5 DESCRIPTION OF THE DEVELOPMENT SYSTEM 5 Switches 6 Jumpers 7 MCU sockets 8 Power Supply 10 On-board 2.0 programmer 11 Oscillator 12 LEDs 1 Pushbutton switches 16 7-segment displays 19 Graphic LCD 20 LCD 2x16 in -bit mode 21 LCD 2x16 in 8-bit mode 22 RS-232 Communication 2 DS1820 Digital Thermometer V voltage regulator 27 Direct Port Access 29 JTAG connector 31 MMC/SD (Multimedia Card) 32 CONTENTS 3

4 User s Manual CONNECTING THE SYSTEM CONNECTING THE SYSTEM Step no.1 Step no.2 Step no.3 Step no. The development system box contains the development system, product CD, cable, RS232 cable and this manual. The first thing to do is to take the system out of the box. Unpack the cable and connect it to the PC. Please use ports on the back of the PC with direct connection to the motherboard. Install the AVRprog programmer and drivers. Start the installation from the product CD: CD_Drive:\product\zip\AVRprog_setup.exe. After the installation connect the cable to the board. You will be asked for the AVRprog drivers. Point to them in order to finish the driver installation. They are placed in the folder: System_Drive:\Program Files\Mikroelektronika\AVRFLASH\Driver.NT Run and use AVRprog as explained in the document AVRprog programmer. CD_Drive:\product\pdf\avrprog_manual.pdf. After these steps, your is installed and ready for use. You can try to read a program from the chip or to load an example from the examples folder of mikroelektronika s compilers for AVR or from the product CD: CD_Drive:\product\zip\easyavr_examples.zip.

5 User s Manual ATMEL AVR DEVELOPMENT BOARD INTRODUCTION The development system is a full-featured development board for Atmel AVR microcontrollers. It has been designed to allow students and engineers to easily exercise and explore the capabilities of AVR microcontrollers. It allows AVR microcontrollers to be interfaced with external circuits and a broad range of peripheral devices, allowing a user to concentrate on software development. Figure 1 illustrates the development board. Each component is marked on a silkscreen, both top and bottom. These marks describe connections to the microcontroller, operation modes, and provide some useful notes. The need for additional schematics is minimized since all relevant information is printed on the board. Figure 1. development board INTRODUCTION 5

6 User s Manual SWITCHES SWITCHES The development board features a number of peripherial devices. In order to enable these devices before programming, you need to check if appropriate jumpers or switches have been properly set. Switches are devices that have two positions - ON and OFF, which have a role to establish or break a connection between two contacts. The development board has three groups of switches. The first group, SW1, enables connections between the microcontroller port with analog capabilities (PORTA) and external pull-up/down resistors. The pull-up/down resistors should be disconnected from the analog input pins, otherwise they will affect the input voltage level. When PORTA pins are used as digital inputs/outputs, the appropriate pullup/down resistors should be enabled. The second group, SW2, is used to enable LEDs connected to PORTA, PORTB, PORTC and PORTD. For example, if the switch for PORTB is OFF, all PORTB LEDs will be turned off. The upper four switches of SW3 are used to enable SPI communication for interfacing with MMC card. The lower four switches of SW3 are used to enable the 7-segment displays. If you don t need the 7-segment displays in your project, these switches should be OFF. Figure 2. Group of 8 switches ON Switch 1 is ON, and other switches are OFF Switch is ON Switch is OFF 6

7 User s Manual JUMPERS Jumpers, like switches, can break or establish a connection between two points. Beneath the plastic cover of the jumper is a metal contact, which makes a connection if the jumper is placed between two disconnected pins. For example, the RS232 communication has two jumpers, J11 and J12, used as switches. They are used to connect or disconnect Rx pin to PD0 and Tx pin to PD1 pin of the microcontroller. A connection is made when the jumpers are placed between two contacts. JUMPERS Figure 3. Jumper as a switch Jumper is ON Jumper is OFF More often jumpers are used as a selector between two possible connections by using a three pin connector. As illustrated in Fig., the middle contact can be connected to the left or right pin, depending on the jumper s position. Figure. Jumper as a multiplexer All lines are disconnected Left line is selected Right line is selected 7

8 User s Manual MCU SOCKETS MCU SOCKETS is delivered with a ATmega16 0-pin microcontroller. Users can remove this one and fit a different microcontroller in DIP0, DIP28, DIP20, DIP18, DIP1 or DIP8 packages of an adequate pinout. Figure 5. MCU sockets Note: There are two DIP0 sockets, with different pinouts (SKT1 and SKT2). When putting 0-pin microcontoller into DIP0 socket choose the one with corresponding pinout. For example, ATmega8535 uses SKT2 socket, while ATmega8515 uses SKT1 socket. Note: Since all packages have parallel connections, there must not be more than one microcontroller on the board at a time. Note: Jumper J13 should be enabled only if you want to use DIP8 microcontroller with external clock source. 8

9 User s Manual Microcontroller s pins are routed to various peripherals as illustrated in Fig. 6. All ports have direct connections to Direct Port Access connectors. Such connectors are typically used for connecting external peripherals to the board or for providing useful points for connecting digital logic probe. All ports are connected to LEDs, push-button switches and pull-up/down resistors, which allow easy monitoring and testing of digital pin state. Some pins are connected to other peripherials such as the DS1820 temperature sensor, RS- 232 communication, 7-segment displays, LCD, etc. MCU SOCKETS PORTB CN2 PORTB SW2 ON J6 PORTB J2 Figure 6. System connection PB DIP0 PA A A DIP28 DIP20 9

10 User s Manual POWER SUPPLY POWER SUPPLY SELECTABLE POWER SUPPLY As a power supply source, users can select either a regulated supply from the cable (default) or an external power supply. In case of the power supply, the system should be connected to a PC using the programming cable, while the jumper J10 should be set in the right-hand position. In the case of an external power supply, the board produces +5V using an LM7805 voltage regulator. The external power supply can be AC or DC, with a voltage between 8V and 16V and the jumper J10 should be set in the left-hand position. In Fig. 7 you can see and external power supply connectors. Figure 8. Power supply select jumper Figure 7. and power supply connectors J10 in the left-hand position: system will take power from the external AC/DC power adapter. connector J10 in the right-hand position: system will take power from the cable. EXT Power Supply EXT External Power Supply CN7 1 2 External power supply connector 8-16V (AC/DC) + E1 70uF 1 REG C1 100nF Vin Vout 2 3 EXT 5V C2 100nF J1 E3 70uF FP1 C9 100nF 5V D- D+ Figure 9. J10 is set to power supply connector 10

11 Reset User s Manual 2.0 IN-CIRCUIT PROGRAMMER ON-BOARD 2.0 PROGRAMMER There is no need for the use of external equipment during programming, as the development system has its own on-board 2.0 programmer. All you need to do is connect the system to a PC using the cable. Then, load your program into the microcontroller via the AVRprog programming software, which is supplied with the board. POWER 1K SWITCH Figure 10. LINK On-Board programmer Note: There is no need for manually reseting MCU after programming. The programmer will reset the MCU automatically. 1K ON-BOARD PROGRAMMER 100n PB XT1 PD0 PD1 PD2 PD3 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 TO PERIPHERALS ON DEVELOPMENT BOARD AVRprog On-Board programmer CN D- 3 D+ 27 CONN. PD PD5 PC1 PC0 PD7 Figure 11. Switch schematic 11

12 User s Manual development board has on-board oscillator circuit for generating microcontroller s clock input. Within the AVRprog programmer you can either choose internal RC oscillator or external clock. External oscillator is connected to the XT1 pin of the microcontroller. Microcontroller in DIP8 package doesn t have pin that is dedicated only for the oscillator clock input. Because of the small pin count, it has PB pin multiplexed between I/O and clock input function. Oscillator Figure 12. If you want to use pin PB with I/O function you should use internal RC oscillator. If you don t need I/O function of the PB pin, then you can use on-board oscillator by enabling jumper J13. By doing this, you are making a direct connection between the oscillator circuit and PB pin. Note: Jumper J13 should be enabled only if you want to use DIP8 microcontroller with external clock source. 12

13 Reset User s Manual J13 PB Figure 13. Oscillator connection with MCU A B 7HC0 F E 100n R7 1M PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 C D R8 1K X2 8MHz C12 22pF C11 22pF Note: In order to simplify the schematics in this manual, the oscillator circuit is represented by this symbol. 13

14 User s Manual LEDs LEDs Light Emitting Diodes (LEDs) are the most commonly used components, usually for displaying pin s digital state. has 32 LEDs that are connected to the microcontroller s PORTA, PORTB, PORTC and PORTD. Figure 1. Light Emitting Diodes Each group of eight LEDs can be enabled or disabled using the switch SW2. Fig. 15. illustrates the connection of a LEDs to PORTA of the microcontroller. A resistor is used in series with the LED to limit the LED's current. In this case the resistor's value is 1K. 1

15 Reset User s Manual The LEDs are enabled when the corresponding switch on SW2 is on. When enabled, LEDs will display the state of the corresponding microcontroller pin; otherwise the LEDs will always be off, no matter what the port state is, as no current can flow through LED. LED schematic Figure 15. PORTA LED ON PORTB LED PORTC LED PORTD LED CURRENT FLOW RN6 R-SIL 8/ PA 100n PB XT1 PD0 PD1 PD2 PD3 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PD PC1 PD5 PC0 PD7 15

16 Reset User s Manual PUSHBUTTON SWITCHES PUSHBUTTON SWITCHES Figure 16. Reset switch 100n has 32 push buttons, which can be used to change states of digital inputs to microcontroller's ports. There is also one switch that acts as a RESET. Reset switch schematic is shown in Figure 17. Figure 17. Reset switch schematic AVRprog On-Board programmer PB XT1 PD0 PD1 PD2 PD3 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PD PC1 PD5 PC0 PD7 Figure 18. Pushbutton switches 16

17 Reset User s Manual Buttons connections to PORTA, PORTB, PORTC and PORTD are shown in Fig. 19. Jumper J6 determines whether a button press will bring logical zero or logical one to the appropriate pin. When button is not pressed, pin state is determined by the pull-up or pull-down port jumpers. In the example shown in Fig. 19, J6 is connected to +5V, therefore pressing the buttons will bring logical one to the appropriate pins. PORTA PORTB PORTC PORTD RA0 RA1 RA2 RA3 RA RA5 RA6 RA7 RB0 RB1 RB2 RB3 RB RB5 RB6 RB7 RC0 RC1 RC2 RC3 RC RC5 RC6 RC7 RD0 RD1 RD2 RD3 RD RD5 RD6 RD7 100n PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 PUSHBUTTON SWITCHES J6 0V while button is pressed +5V while button is pressed Figure 19. Buttons schematic 17

18 User s Manual PUSHBPUSHBUTTON SWITCHES On Fig. 20 the J1 jumper is set to pull-up, therefore when the button is not pressed, pull-up resistor pulls the microcontroller s pin to +5V. A button press causes the port pin to be connected to ground (J6 is in the lower position). Thus, only when the button is pressed the microcontroller will sense a logical zero; otherwise the pin state will always be logical one. On Fig. 21 the J6 jumper is set to pull-down, therefore when the button is not pressed, pulldown resistor pulls the microcontroller s pin to 0V. A button press causes the port pin to be connected to +5V (J6 is in the higher position). PB ATMEGA PA A A Figure 20. SW1 vcc J1 PORTA pull-up ON vcc J6 0V while pressed Button with pull-up resistor SW1 vcc J1 PORTA pull-down ON Thus, only when the button is pressed the microcontroller will sense a logical one; otherwise the pin state will always be logical zero. PB ATMEGA PA A A vcc J6 5V while pressed Figure 21. Button with pull-down resistor 18

19 Reset User s Manual 7 S E G 8. R E A D Y 7-SEGMENT DISPLAYS has four 7-segment displays in multiplex mode. Data lines are connected to PORTA, while each display is enabled through the lower four bits of PORTB. Figure segment displays a 8. f b g e c dp d DIS3 DIS2 DIS1 DIS0 100n PB XT1 PD0 PD1 PD2 PD3 PD ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 R2-R9 a b c d e f g dp R28 Q Q2 Q3 R29 R30 R Q PD5 PC0 PD7 SW3 PB ON SCK MISO MOSI MMC-CS DIS3 DIS2 DIS1 DIS0 Figure segment displays schematic 19

20 Reset User s Manual GRAPHIC LCD 128X6 GRAPHIC LCD CONNECTOR ON-BOARD GRAPHIC LCD A graphic LCD (GLCD) allows advanced visual messages to be displayed. While a character LCD can display only alphanumeric characters, a GLCD can be used to display messages in the form of drawings and bitmaps. The most commonly used graphic LCD has the screen resolution of 128x6 pixels. Before a GLCD is connected, the user needs to set the jumper J8 (Fig. 2) to the upper position. The GLCD s contrast can be adjusted using the potentiometer P1, which is placed to the right of the GLCD. Figure 2. GLCD selection jumper In order to enable GLCD, jumper J8 should be set to the upper position, labeled as GRAPH. GLCD Figure 25. J8 GRAPH. CHAR. Contrast Adjustment Figure 26. GLCD schematic P1 Vo Vee PD2 PD3 PD PD5 PA PD CS1 CS2 Vo RS R/W E D0 D1 D2 D3 D D5 D6 D7 Vee LED+ LED- GLCD contrast selected R19 10 LCD8 contrast selected GLCD and LCD8 contrast not selected 100n CS1 CS2 RS R/W E PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 D0 D1 D2 D3 D D5 D6 D7 20

21 E Reset User s Manual 2x16 LCD CONNECTOR 2x16 LCD ON-BOARD LCD 2X16 IN -BIT MODE A standard character LCD is probably the most widely used data visualization component. Usually, it can display two lines of 16 alphanumeric characters, each made up of 5x8 pixels. The character LCD communicates with the microcontroller via a -bit or 8-bit data bus, each requiring the use of a different connector on. For -bit data bus use, the LCD should be placed in the upper left of the board, just above the LEDs. The connection to the microcontroller is shown in Fig. 28 where there are only four data lines. It is important to note that the LCD should be placed or removed from only when the power is off. Figure 27. LCD 2x16 in -bit mode LCD 2X16 IN -BIT MODE Figure 28. LCD 2x16 in -bit mode schematics P2 Contrast Adjustment 1 1 VEE RS R/W PD PA D0 D1 D2 D3 D D5 D6 D7 LCD Display -bit mode 100n RS E PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 D D5 D6 D7 21

22 User s Manual LCD IN 8-BIT MODE 2x16 LCD CONNECTOR 2x16 LCD ON-BOARD LCD 2X16 IN 8-BIT MODE When using a character LCD in 8-bit mode, the connector that is shared with the GLCD should be used. Since this connector has 20 pins and the character LCD has only 1 pins, special attention is required when placing the LCD. Otherwise the LCD can be permanently damaged. Figure 29. LCD 2x16 in 8-bit mode View from the back: shows which pins stays disconnected. The LCD must be placed in the marked position with two free pins to the left and four free pins to the right. It is important to note that the LCD should be placed or removed from only when the power is off. Before attaching the LCD, set jumper J8 to the lower position. The LCD's contrast can be adjusted using potentiometer P1 which is located to the right of the GLCD/LCD connector. NOTE: Special attention is required when placing the LCD. Otherwise the LCD can be permanently damaged. 22

23 Reset User s Manual J8 GRAPH. CHAR. Contrast Adjustment P1 Leave two free pins to the left side Vo Vee PD PD5 PA 1 1 VEE RS R/W E D0 D1 D2 D3 D D5 D6 D7 GLCD contrast selected LCD Display 8-bit mode In order to enable LCD, jumper J8 should be set to the lower position, labeled as CHAR. LCD8 contrast selected Leave four free pins to the right side GLCD and LCD8 contrast not selected 100n RS R/W E PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 D0 D1 D2 D3 D D5 D6 D7 LCD 2X16 IN 8-BIT MODE Figure 30. LCD 8-bit mode schematic 23

24 User s Manual RS-232 COMMUNICATION RS232 ENABLED RS-232 COMMUNICATION RS-232 communication enables point-to-point data transfer. It is commonly used in data acquisition applications, for the transfer of data between the microcontroller and a PC. Since the voltage levels of a microcontroller and PC are not directly compatible with each other, a level transition buffer such as the MAX232 must be used. Figure 31. RS232 connectors In order to provide a more flexible system, the microcontroller is connected to the MAX232 through the two jumpers: J11 and J12. The jumper J11 is used to connect the Rx line to PD0 pin. The jumper J12 is used to connect the Tx line to PD1 pin. 2

25 Reset User s Manual RS-232 CON SERIAL CABLE RS-232 A CON E9 10uF E11 10uF E10 10uF C18 100nF C1+ VS+ C1- C2+ C2- VS- T2OUT R2IN 1 5 U6 MAX T1OUT R1IN R1OUT T1IN T2IN R2OUT RS232 COMM. Disabled 9 E12 10uF J12 CONNECT MCU TO PC CONNECT PC TO MCU CN9 SUB-D 9p J11 RS232 COMM. Enabled Receive data (Rx) Send Data (Tx) Rx Tx Figure 32. Connection between microcontroller and a PC 100n PC PB XT1 PD0 PD1 PD2 PD3 PD ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 RS-232 COMMUNICATION PD5 PC0 PD7 25

26 Reset User s Manual DS1820 DIGITAL THERMOMETER DS1820 DIGITAL THERMOMETER DS1820 digital thermometer is well suited to environmental temperature measurement, having the temperature range of -55 C to 125 C and the accuracy of +/-0.5 C. It must be placed correctly in the 3- pin socket provided on, with its rounded side to the lower edge of the board (see Fig. 33) otherwise the DS1820 could be permanently damaged. DS1820 s data pin can be connected to either PC6 or pin, which is determined by jumper J7. There is a mark in the form of half-circle for proper orientation of DS1820 sensor. DS1820 DQ 125 C -55 C R1 J7 100n PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 Figure 33. DS1820 PD7 DQ line is connected to PC6 DQ line is connected to DQ line is disconnected Figure 3. DS1820 schematic 26

27 User s Manual VREF.096V ON-BOARD.096V VOLTAGE REFERENCE Some of the Atmel s microcontrollers have integrated A/D Converter (Analog-to-Digital Converter). In order for A/D Converter to work, voltage reference must be used. It represents a maximum value that can be measured by microcontroller. uses.096v voltage reference because number 096 is a power of 2 which makes it easy to represent values as binary numbers in microcontroller. In case of the 10-bit A/D Converter the resolution will be mv per bit. In case of the 12-bit A/D Converter the resolution will be 1mV per bit. Figure V voltage reference.096v VOLTAGE REFERENCE Analog input pins are placed on PORTA of microcontroller. In order to measure analog signal without interference, turn the coresponding switch on SW1 to OFF position. This will disable connection of the used PORTA pin to the pull-up/down resistors. Applications of A/D Conversion are various. Microcontroller takes analog signal from its input pin and translates it into a digital value. Basically, you can measure any analog signal that fits in range acceptable by MCU. With.096V voltage reference used (jumper J9 in lower position) this range is 0V-.096V. If you place jumper J9 in upper position 5V will be used as voltage reference and therefor measure range will be 0V-5V. 27

28 Reset User s Manual.096V VOLTAGE REFERENCE.096V voltage reference VIN Pull-up/down resistors on PORTA analog input pins should be disabled using SW1 REF1 MCP VOUT 5V voltage reference R J9 R12 1K 100n E1 10uF PB XT1 PD0 PD1 PD2 PD3 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 SW1 ADC0 ADC1 ADC2 ADC3 ADC ADC5 ADC6 ADC7 vcc J1 PORTA ON pull-up PD PC1 PD5 PC0 PD7 Figure V voltage reference schematic 28

29 User s Manual DIRECT PORT ACCESS All microcontroller input/output pins can be accessed via connectors placed along the right side of the board. For each of PORTA, PORTB, PORTC, PORTD and PORTE there is one 10-pin connector providing, and up to eight port pins. DIRECT PORT ACCESS Figure 37. Direct port access connectors These connectors can be used for system expansion with external boards such as Serial Ethernet, Compact Flash, MMC/SD, ADC, DAC, CAN, RTC, RS-85, etc. Ensure that the on-board peripherals are disconnected from microcontroller by setting the appropriate jumpers, while external peripherals are using the same pins. The connectors can also be used for attaching logic probes or other test equipment. Figure 38. Example of how to connect external peripheral with flat cable 29

30 Reset User s Manual DIRECT PORT ACCESS 100n PB XT1 PD0 PD1 PD2 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC PC5 PC6 1 PC0 2 PC1 3 PC2 PC J3 2 3 RN3 RPACK8/9 8x Pull-down line is connected Pull-up line is connected All lines are disconnected PD3 PC2 PD PC1 PD5 PC0 PD7 CN3 PC0 PC1 Figure 39. PORTC connection PC2 PC PC6 PC3 PC5 HEADER 5x2 30

31 Reset User s Manual JTAG CONNECTOR 100n JTAG connector can be used as serial programming interface or On-Chip debug system. For the On-chip Debug system, in addition to the JTAG interface pins, the RESET pin is monitored by the debugger to be able to detect external reset sources. The debugger can also pull the RESET pin low to reset the whole system. The JTAG interface is accessed through four of the microcontroller s pins: - TMS: Test Mode Select, - TCK: Test Clock, - TDI: Test Data In, - TDO: Test Data Out. m Figure 0. PB XT1 PD0 PD1 PD2 PD3 PD PD5 ATMEGAxxxx JTAG connector schematic PA A A PC6 PC5 PC PC3 PC2 PC1 PC0 PD7 Vsupply JTAG CONNECTOR CN6 TCK TDO VTref TMS ns nt TDI m NC JTAG CONNECTOR HEADER 5x2 31

32 User s Manual MMC/SD (MULTIMEDIA) CARD MMC/SD MASS STORAGE 256MB SUPPORTED MMC/SD (MULTIMEDIA CARD) MMC card is used as storage media for a portable devices, in a form that can easily be removed for access by a PC. For example, a digital camera would use an MMC card for storing image files. With an MMC reader (typically small box that connects via or some other serial connection) you can easily transfer data from MMC card to your computer. Microcontroller on communicates with Multi Media Card via SPI communication. Modern computers, both laptops and desktops, often have SD slots, which can read MMC cards. Figure 1. MMC slot on-board To enable MMC card you must turn on switches 1, 2, 3 and on SW3. By doing that, microcontroller s SPI comunnication lines (SDI, SDO and SCK) and Chip Select are connected to MMC. Working voltage of is 5V DC, while working voltage of MMC card is 3.3V DC. Because of that, there is a voltage regulator on-board with MMC card (MC33269DT-3.3). Data lines from microcontroller to MMC card must be also adjusted to 3.3V. It is done with resister voltage dividers as shown on Figure 2. 32

33 Reset User s Manual SPI-SDI MMC-CS# SPI-SDO SPI-SCK SPI-SCK SPI-SDI SPI-SDO MMC-CS# R13 2K2 R1 3K3 3 R15 2K2 R16 3K3 C20 100nF SW3 R17 2K2 R18 3K3 ON REG2 MC33269 DT C nF VIN 1 2 VOUT 3 PB 3 E15 10uF CS Din +3.3V SCK Dout 100n CN12 MMC/SD CARD PB XT1 PD0 PD1 PD2 PD3 ATMEGAxxxx PA A A PC6 PC5 PC PC3 PC2 MMC/SD (MULTIMEDIA CARD) PD PC1 PD5 PC0 PD7 MMC schematic Figure 2. 33

34 User s Manual If you are experiencing problems with any of our products or you just want additional information, please let us know. We are committed to meeting your every need. Technical Support : support@mikroe.com If you have any other question, comment or a business proposal, please contact us: office@mikroe.com Web: Forum: 3