I'm trying to make a project in Codevison, with ATMEGA164a, to be more specific, a contactless card reader with RFID-RC522. This project requires two interfaces, User-'U' and Admin-'A'. I started to implement the Admin menu, which allows to delete-'D', view-'V' and enroll-'E' a card and I have a problem when I have to enroll the key tag. When I'm trying to call the RFID's functions, especially those two: " mfrc522_init(); " and " byte = mfrc522_request(PICC_REQALL,str); ", but it doesn't do the right thing and it brings me back to the main menu. How can I fix it? Thank you.
**The enroll main code :**
else if(temp == 'E'|| temp == 'e'){
lcd_clear();
flag = 1;
spi_init();
mfrc522_init();
lcd_putsf("Enroll");
byte = mfrc522_request(PICC_REQALL,str);
if(byte == CARD_FOUND){
byte = mfrc522_get_card_serial(str);
}
while(flag){
byte = mfrc522_request(PICC_REQALL,str);
if(byte == CARD_FOUND){
temp2[0] = '\0';
for(byte=0;byte<5;byte++) {
itoa(str[byte],rez);
strcat(temp2,rez);
}
flag = 0;
}
else{
lcd_clear();
lcd_putsf("Erorr");
delay_ms(3000);
lcd_clear();
}
}
if(!strcmp(card1,temp2)) lcd_putsf("Card 1 exists.");
else if(!strcmp(card2,temp2)) lcd_putsf("Card 2 exists.");
else if(!strcmp(card3,temp2)) lcd_putsf("Card 3 exists.");
else if(card_empty_check(1)) {
strcpy(card1,temp2);
write_card(1);
lcd_putsf("Card 1 saved.");
}
else if(card_empty_check(2)) {
strcpy(card2,temp2);
write_card(2);
lcd_putsf("Card 2 saved.");
}
else if(card_empty_check(3)){
strcpy(card3,temp2);
write_card(3);
lcd_putsf("Card 3 saved.");
}else lcd_putsf("No space.");
//delay_ms(1000);
}
`
**The functions called:**
char card1[11];
char card2[11];
char card3[11];
char empty[] = "0000000000";
int card1_empty = 0;
int card2_empty = 0;
int card3_empty = 0;
void write_card(int n){
if(n == 1) eeprom_write_block((void*)&card1, (eeprom void*)0, 10);
if(n == 2) eeprom_write_block((void*)&card2, (eeprom void*)10, 10);
if(n == 3) eeprom_write_block((void*)&card3, (eeprom void*)20, 10);
}
int card_empty_check(int n) {
if(n == 1) {
if(!strcmp(card1,empty)) return 1;
}
if(n == 2) {
if(!strcmp(card2,empty)) return 1;
}
if(n == 3) {
if(!strcmp(card3,empty)) return 1;
}
return 0;
}
int full_card_empty_check() {
for(i = 1; i < 4; i++) {
if(!card_empty_check(i)) return 0;
}
return 1;
}
**mfrc522.c:**
#include "mfrc522.h"
#include "spi.h"
#include <mega164a.h>
#if 1
#include <alcd.h>
#endif
#define MFRC522_RST PORTB.0
#define MFRC522_SS PORTB.4
void mfrc522_init()
{
uint8_t byte;
mfrc522_reset();
mfrc522_write(TModeReg, 0x8D);
mfrc522_write(TPrescalerReg, 0x3E);
mfrc522_write(TReloadReg_1, 30);
mfrc522_write(TReloadReg_2, 0);
mfrc522_write(TxASKReg, 0x40);
mfrc522_write(ModeReg, 0x3D);
byte = mfrc522_read(TxControlReg);
if(!(byte&0x03))
{
mfrc522_write(TxControlReg,byte|0x03);
}
}
void mfrc522_write(uint8_t reg, uint8_t data)
{
ENABLE_CHIP();
spi_transmit((reg<<1)&0x7E);
spi_transmit(data);
DISABLE_CHIP();
}
uint8_t mfrc522_read(uint8_t reg)
{
uint8_t data;
ENABLE_CHIP();
spi_transmit(((reg<<1)&0x7E)|0x80);
data = spi_transmit(0x00);
DISABLE_CHIP();
return data;
}
void mfrc522_reset()
{
mfrc522_write(CommandReg,SoftReset_CMD);
}
uint8_t mfrc522_request(uint8_t req_mode, uint8_t * tag_type)
{
uint8_t status;
uint32_t backBits;//The received data bits
mfrc522_write(BitFramingReg, 0x07);//TxLastBists = BitFramingReg[2..0]
tag_type[0] = req_mode;
status = mfrc522_to_card(Transceive_CMD, tag_type, 1, tag_type, &backBits);
if ((status != CARD_FOUND) || (backBits != 0x10))
{
status = ERROR;
}
return status;
}
uint8_t mfrc522_to_card(uint8_t cmd, uint8_t *send_data, uint8_t send_data_len, uint8_t *back_data, uint32_t *back_data_len)
{
uint8_t status = ERROR;
uint8_t irqEn = 0x00;
uint8_t waitIRq = 0x00;
uint8_t lastBits;
uint8_t n;
uint8_t tmp;
uint32_t i;
switch (cmd)
{
case MFAuthent_CMD: //Certification cards close
{
irqEn = 0x12;
waitIRq = 0x10;
break;
}
case Transceive_CMD: //Transmit FIFO data
{
irqEn = 0x77;
waitIRq = 0x30;
break;
}
default:
break;
}
//mfrc522_write(ComIEnReg, irqEn|0x80); //Interrupt request
n=mfrc522_read(ComIrqReg);
mfrc522_write(ComIrqReg,n&(~0x80));//clear all interrupt bits
n=mfrc522_read(FIFOLevelReg);
mfrc522_write(FIFOLevelReg,n|0x80);//flush FIFO data
mfrc522_write(CommandReg, Idle_CMD); //NO action; Cancel the current cmd???
//Writing data to the FIFO
for (i=0; i<send_data_len; i++)
{
mfrc522_write(FIFODataReg, send_data[i]);
}
//Execute the cmd
mfrc522_write(CommandReg, cmd);
if (cmd == Transceive_CMD)
{
n=mfrc522_read(BitFramingReg);
mfrc522_write(BitFramingReg,n|0x80);
}
//Waiting to receive data to complete
i = 2000; //i according to the clock frequency adjustment, the operator M1 card maximum waiting time 25ms???
do
{
//CommIrqReg[7..0]
//Set1 TxIRq RxIRq IdleIRq HiAlerIRq LoAlertIRq ErrIRq TimerIRq
n = mfrc522_read(ComIrqReg);
i--;
}
while ((i!=0) && !(n&0x01) && !(n&waitIRq));
tmp=mfrc522_read(BitFramingReg);
mfrc522_write(BitFramingReg,tmp&(~0x80));
if (i != 0)
{
if(!(mfrc522_read(ErrorReg) & 0x1B)) //BufferOvfl Collerr CRCErr ProtecolErr
{
status = CARD_FOUND;
if (n & irqEn & 0x01)
{
status = CARD_NOT_FOUND; //??
}
if (cmd == Transceive_CMD)
{
n = mfrc522_read(FIFOLevelReg);
lastBits = mfrc522_read(ControlReg) & 0x07;
if (lastBits)
{
*back_data_len = (n-1)*8 + lastBits;
}
else
{
*back_data_len = n*8;
}
if (n == 0)
{
n = 1;
}
if (n > MAX_LEN)
{
n = MAX_LEN;
}
//Reading the received data in FIFO
for (i=0; i<n; i++)
{
back_data[i] = mfrc522_read(FIFODataReg);
}
}
}
else
{
status = ERROR;
}
}
//SetBitMask(ControlReg,0x80); //timer stops
//mfrc522_write(cmdReg, PCD_IDLE);
return status;
}
uint8_t mfrc522_get_card_serial(uint8_t * serial_out)
{
uint8_t status;
uint8_t i;
uint8_t serNumCheck=0;
uint32_t unLen;
mfrc522_write(BitFramingReg, 0x00); //TxLastBists = BitFramingReg[2..0]
serial_out[0] = PICC_ANTICOLL;
serial_out[1] = 0x20;
status = mfrc522_to_card(Transceive_CMD, serial_out, 2, serial_out, &unLen);
if (status == CARD_FOUND)
{
//Check card serial number
for (i=0; i<4; i++)
{
serNumCheck ^= serial_out[i];
}
if (serNumCheck != serial_out[i])
{
status = ERROR;
}
}
return status;
}
