Fingerprint Scanner API using GT511C3 fingerprint scanner.
Dependencies: 4DGL-uLCD-SE GT511C3 SDFileSystem mbed
Fork of GT511C3test by
The fingerprint scanner is designed to take attendance over a group of students. It requires a the group owner to store a preloaded list of student id numbers in a .txt file to the memory (SD card) in return of a 5 digits keypass to gain access to the database when taking attendance.
While there may exist multiple group owner and a group owner with multiple databases, each group will be uniquely identified by the 5 digits keypass. The program limits each scanner to open ONE session at a time where only one group will be able to take attendance during its session. Once a session is closed, a report of the attendance taken during the open session is generated and sent via ethernet to owner and there is no way to reopen the session again.
For the initial setup, each fingerprint database needs to be populated by the students. This set up can be done continuously during a session while taking attendance that session.
i2c.h
- Committer:
- yoshua0207
- Date:
- 2015-12-01
- Revision:
- 8:a1ba925cf903
File content as of revision 8:a1ba925cf903:
// This library provides the high-level functions needed to use the I2C // serial interface supported by the hardware of several AVR processors. #include <avr/io.h> #include <avr/interrupt.h> #include "types.h" #include "defs.h" // TWSR values (not bits) // (taken from avr-libc twi.h - thank you Marek Michalkiewicz) // Master #define TW_START 0x08 #define TW_REP_START 0x10 // Master Transmitter #define TW_MT_SLA_ACK 0x18 #define TW_MT_SLA_NACK 0x20 #define TW_MT_DATA_ACK 0x28 #define TW_MT_DATA_NACK 0x30 #define TW_MT_ARB_LOST 0x38 // Master Receiver #define TW_MR_ARB_LOST 0x38 #define TW_MR_SLA_ACK 0x40 #define TW_MR_SLA_NACK 0x48 #define TW_MR_DATA_ACK 0x50 #define TW_MR_DATA_NACK 0x58 // Slave Transmitter #define TW_ST_SLA_ACK 0xA8 #define TW_ST_ARB_LOST_SLA_ACK 0xB0 #define TW_ST_DATA_ACK 0xB8 #define TW_ST_DATA_NACK 0xC0 #define TW_ST_LAST_DATA 0xC8 // Slave Receiver #define TW_SR_SLA_ACK 0x60 #define TW_SR_ARB_LOST_SLA_ACK 0x68 #define TW_SR_GCALL_ACK 0x70 #define TW_SR_ARB_LOST_GCALL_ACK 0x78 #define TW_SR_DATA_ACK 0x80 #define TW_SR_DATA_NACK 0x88 #define TW_SR_GCALL_DATA_ACK 0x90 #define TW_SR_GCALL_DATA_NACK 0x98 #define TW_SR_STOP 0xA0 // Misc #define TW_NO_INFO 0xF8 #define TW_BUS_ERROR 0x00 // defines and constants #define TWCR_CMD_MASK 0x0F #define TWSR_STATUS_MASK 0xF8 // return values #define I2C_OK 0x00 #define I2C_ERROR_NODEV 0x01 #define sbi(var, mask) ((var) |= (uint8_t)(1 << mask)) #define cbi(var, mask) ((var) &= (uint8_t)~(1 << mask)) #define WRITE_sda() DDRC = DDRC | 0b00010000 //SDA must be output when writing #define READ_sda() DDRC = DDRC & 0b11101111 //SDA must be input when reading - don't forget the resistor on SDA!! // functions //! Initialize I2C (TWI) interface void i2cInit(void); //! Set the I2C transaction bitrate (in KHz) void i2cSetBitrate(unsigned short bitrateKHz); // Low-level I2C transaction commands //! Send an I2C start condition in Master mode void i2cSendStart(void); //! Send an I2C stop condition in Master mode void i2cSendStop(void); //! Wait for current I2C operation to complete void i2cWaitForComplete(void); //! Send an (address|R/W) combination or a data byte over I2C void i2cSendByte(unsigned char data); //! Receive a data byte over I2C // ackFlag = TRUE if recevied data should be ACK'ed // ackFlag = FALSE if recevied data should be NACK'ed void i2cReceiveByte(unsigned char ackFlag); //! Pick up the data that was received with i2cReceiveByte() unsigned char i2cGetReceivedByte(void); //! Get current I2c bus status from TWSR unsigned char i2cGetStatus(void); void delay_ms(uint16_t x); // high-level I2C transaction commands //! send I2C data to a device on the bus (non-interrupt based) unsigned char i2cMasterSendNI(unsigned char deviceAddr, unsigned char length, unsigned char* data); //! receive I2C data from a device on the bus (non-interrupt based) unsigned char i2cMasterReceiveNI(unsigned char deviceAddr, unsigned char length, unsigned char *data); /********************* ****I2C Functions**** *********************/ void i2cInit(void) { // set i2c bit rate to 40KHz i2cSetBitrate(100); // enable TWI (two-wire interface) sbi(TWCR, TWEN); // Enable TWI } void i2cSetBitrate(unsigned short bitrateKHz) { unsigned char bitrate_div; // set i2c bitrate // SCL freq = F_CPU/(16+2*TWBR)) cbi(TWSR, TWPS0); cbi(TWSR, TWPS1); //calculate bitrate division bitrate_div = ((F_CPU/4000l)/bitrateKHz); if(bitrate_div >= 16) bitrate_div = (bitrate_div-16)/2; outb(TWBR, bitrate_div); } void i2cSendStart(void) { WRITE_sda(); // send start condition TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN); } void i2cSendStop(void) { // transmit stop condition TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO); } void i2cWaitForComplete(void) { int i = 0; //time out variable // wait for i2c interface to complete operation while ((!(TWCR & (1<<TWINT))) && (i < 90)) i++; } void i2cSendByte(unsigned char data) { delay_ms(1); //printf("sending 0x%x\n", data); WRITE_sda(); // save data to the TWDR TWDR = data; // begin send TWCR = (1<<TWINT)|(1<<TWEN); } void i2cReceiveByte(unsigned char ackFlag) { // begin receive over i2c if( ackFlag ) { // ackFlag = TRUE: ACK the recevied data outb(TWCR, (inb(TWCR)&TWCR_CMD_MASK)|BV(TWINT)|BV(TWEA)); } else { // ackFlag = FALSE: NACK the recevied data outb(TWCR, (inb(TWCR)&TWCR_CMD_MASK)|BV(TWINT)); } } unsigned char i2cGetReceivedByte(void) { // retieve received data byte from i2c TWDR return( inb(TWDR) ); } unsigned char i2cGetStatus(void) { // retieve current i2c status from i2c TWSR return( inb(TWSR) ); } void delay_ms(uint16_t x) { uint8_t y, z; for ( ; x > 0 ; x--){ for ( y = 0 ; y < 90 ; y++){ for ( z = 0 ; z < 6 ; z++){ asm volatile ("nop"); } } } }