Interfacing RTC DS1307

Hello Kishore,

It seems that the search system has failed on TM4C (unwanted side effect of the update). In the meantime can you please describe the issue, attach the code and scope/LA waveform of what you are seeing?

Regards

Amit

Hi,
Following is my code, I have connected SCL to PB2 and SDA to PB3,along with that I have connected 4.7k pullup reistors with SCL and SDA .I am trying to print the output on my serial monitor through UART but I am not getting any response over there.Please help me debug my code!!!!

• board-Tm4C123G Launchpad
• crystal frequency-32.768 Khz

#include "hw_memmap.h"
#include "hw_types.h"
#include "hw_i2c.h"
#include "i2c.h"
#include "sysctl.h"
#include "gpio.h"
#include "uartstdio.h"
#include "systick.h"
#include "uart.h"
//#include "Debug1.h"
#include "ustdlib.h"

#define BYTE unsigned char
#define SLAVE_ADDRESS 0x68
extern void InitConsole(void);
extern unsigned char dec2bcd(unsigned char val) ;
extern unsigned char bcd2dec(unsigned char val) ;



unsigned char dec2bcd(unsigned char val)
{
return ((val/0xA*0x10)+(val%0xA));
}

// convert BCD to binary
unsigned char bcd2dec(unsigned char val)
{
return ((val/0x10*0xA)+(val%0x10));
}
void InitConsole(void)
{

SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);

GPIOPinConfigure(GPIO_PA0_U0RX);
GPIOPinConfigure(GPIO_PA1_U0TX);

GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);

UARTStdioInit(0);
}

int main()
{
unsigned long sec=3,min =59,hour = 12,day = 4,date = 3,month = 12,year = 10,tsec,tmin,thour,tday,tdate,tmonth,tyear;
unsigned char Last_Value = 1;
SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN | SYSCTL_XTAL_8MHZ);
InitConsole();

SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C0);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
SysTickPeriodSet(SysCtlClockGet());
SysTickEnable();

GPIOPinConfigure(GPIO_PB2_I2C0SCL);
GPIOPinConfigure(GPIO_PB3_I2C0SDA);
GPIOPinTypeI2C(GPIO_PORTB_BASE, GPIO_PIN_2 | GPIO_PIN_3);

I2CMasterInitExpClk(I2C0_MASTER_BASE, SysCtlClockGet(), false);
I2CMasterSlaveAddrSet(I2C0_MASTER_BASE, SLAVE_ADDRESS , false);

I2CMasterDataPut(I2C0_MASTER_BASE, 0);
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_START);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(sec));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(min));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(hour));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(day));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(date));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(month));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterDataPut(I2C0_MASTER_BASE, dec2bcd(year));
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_FINISH);
while(I2CMasterBusy(I2C0_MASTER_BASE));

while(1)
{
I2CMasterSlaveAddrSet(I2C0_MASTER_BASE, SLAVE_ADDRESS , false);
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_START);

I2CMasterDataPut(I2C0_MASTER_BASE, 0x00);
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_SEND_FINISH);
while(I2CMasterBusy(I2C0_MASTER_BASE));

I2CMasterSlaveAddrSet(I2C0_MASTER_BASE, SLAVE_ADDRESS , true);
I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_START);
while(I2CMasterBusy(I2C0_MASTER_BASE));
sec = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
min = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
hour = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
day = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
date = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
month = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while(I2CMasterBusy(I2C0_MASTER_BASE));
year = I2CMasterDataGet(I2C0_MASTER_BASE);

I2CMasterControl(I2C0_MASTER_BASE, I2C_MASTER_CMD_BURST_RECEIVE_FINISH);
while(I2CMasterBusy(I2C0_MASTER_BASE));

tsec = bcd2dec(sec)&0x7f;
tmin = bcd2dec(min);
thour = bcd2dec(hour)&0x3f;
tday = bcd2dec(day);
tdate = bcd2dec(date);
tmonth = bcd2dec(month);
tyear = bcd2dec(year);
if(Last_Value != tsec)
{

UARTprintf("%02d:%02d:%02d \n%02d %02d/%02d/%02d\n",thour,tmin,tsec,tday,tdate,tmonth,tyear);
Last_Value = tsec;
tsec = 0;
}

}


}