LCD 12864 interface with TM4C1294 Launchpad

HAROON AHMED

Other Parts Discussed in Thread: TM4C1294NCPDT

Hi Everyone !

I have re-wrote the code as per guidelines for LCD 12864B with TM4C Launchpad, but still nothing is being written to LCD, I do not know, what's wrong with the code

I am pasting my code , please help me .

I have connected many other devices and sensors with Launchpad, so just few GPIO pins left, that's why I am unable to use consecutive pins for LCD, I have to manage the interfacing with these pins as instructed. please help me to debug with it.

LCD controller is ST7920. If anyone have already used this LCD , please let me know some sample code for it that help me identify my mistakes and misunderstandings as well.

following is link to lcd controller datasheet:

#include <stdint.h>
#include "inc/tm4c1294ncpdt.h"
#include <stdbool.h>
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"
#include"inc/hw_types.h"
#include"inc/hw_memmap.h"
#include"driverlib/timer.h"
#include"driverlib/interrupt.h"
#include"driverlib/systick.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"

//*****************************************************************************

void delay(uint32_t num);
volatile unsigned long long int clock,period;
int
main(void)
{

//Clock Set
clock=SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ |SYSCTL_OSC_MAIN | SYSCTL_USE_PLL |SYSCTL_CFG_VCO_480), 120000000);
//Port Initialization-Used many ports, beacuse few pins left, i have not left any free
//conscutive pins to connect with lcd, rest of all pins connected with sensors and other devices
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPION);
SysCtlPeripheralEnable(SYSCTL_PERIPH_TIMER0);
GPIOPinTypeGPIOOutput(GPIO_PORTN_BASE,GPIO_PIN_0);
period=clock;

//Port Initialization-Used many ports, beacuse few pins left, i have not left any free
//conscutive pins to connect with lcd, rest of all pins connected with sensors and other devices
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOH);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOM);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOE);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOK);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPION);

//DATA-SIGNALS
GPIOPinTypeGPIOOutput(GPIO_PORTA_BASE,GPIO_PIN_4|GPIO_PIN_5);//DB0,DB1
GPIOPinTypeGPIOOutput(GPIO_PORTH_BASE,GPIO_PIN_1);//DB2
GPIOPinTypeGPIOOutput(GPIO_PORTM_BASE,GPIO_PIN_4);//DB3
GPIOPinTypeGPIOOutput(GPIO_PORTE_BASE,GPIO_PIN_4|GPIO_PIN_5);//DB4&DB5
GPIOPinTypeGPIOOutput(GPIO_PORTN_BASE,GPIO_PIN_4|GPIO_PIN_5);//DB6, DB7

//CONTROL-SIGNALS RS, R/W AND EN
GPIOPinTypeGPIOOutput(GPIO_PORTB_BASE,GPIO_PIN_4|GPIO_PIN_5);//RS,R/W
GPIOPinTypeGPIOOutput(GPIO_PORTK_BASE,GPIO_PIN_2);//EN
//RESET-RST
GPIOPinTypeGPIOOutput(GPIO_PORTM_BASE,GPIO_PIN_6);
//PSB
GPIOPinTypeGPIOOutput(GPIO_PORTK_BASE,GPIO_PIN_3);

//Reset low to high delay
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_6,0);
//PSB- PARALLEL
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_3,1);
delay(4800000);
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_6,1);

//function set
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB0,DB1
GPIOPinWrite(GPIO_PORTH_BASE,GPIO_PIN_1,0);//DB2
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_4,0);//DB3
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_4,1);//DB4
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_5,1);//DB5
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB6, DB7
//RS/RW
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//RS|RW
//EN
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,0);
delay(16800);
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,1);

delay(12000);
//display-on-Off
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB0,DB1
GPIOPinWrite(GPIO_PORTH_BASE,GPIO_PIN_0,0);//DB2
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_4,1);//DB3
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB4&DB5
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB6, DB7
//rs-rw
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_4|GPIO_PIN_5,0);
//en
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,0);
SysCtlDelay(12000);
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,1);

SysCtlDelay(12000);
//display clear

GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4,1);//DB0
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4,0);//DB1
GPIOPinWrite(GPIO_PORTH_BASE,GPIO_PIN_0,0);//DB2
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_4,0);//DB3
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB4&DB5
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB6, DB7
//RS-R/W
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_4|GPIO_PIN_5,0);
//EN
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,0);
delay(1200000);
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,1);

SysCtlDelay(1200000);

//ENTRY-MODE-SET
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4,1);//DB0
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_5,1);//DB1
GPIOPinWrite(GPIO_PORTH_BASE,GPIO_PIN_0,1);//DB2
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_4,0);//DB3
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB4&DB5
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB6, DB7
//RS-R/W
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_4|GPIO_PIN_5,0);
//EN
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,0);
SysCtlDelay(2000000);
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,1);

SysCtlDelay(1200000);
//WRITING 0x41 "A" to DATA-bus DB0-DB7
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_4,1);//DB0
GPIOPinWrite(GPIO_PORTA_BASE,GPIO_PIN_5,0);//DB1
GPIOPinWrite(GPIO_PORTH_BASE,GPIO_PIN_0,0);//DB2
GPIOPinWrite(GPIO_PORTM_BASE,GPIO_PIN_4,0);//DB3
GPIOPinWrite(GPIO_PORTE_BASE,GPIO_PIN_4|GPIO_PIN_5,0);//DB4&DB5
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_4,1);//DB6,
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_5,0);//DB7
//RS-R/W
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_4,1);//RS
GPIOPinWrite(GPIO_PORTB_BASE,GPIO_PIN_5,0);//R/W
//EN
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,0);
SysCtlDelay(12000);
GPIOPinWrite(GPIO_PORTK_BASE,GPIO_PIN_2,1);

while(1){
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_0,1);
delay(period/2);
GPIOPinWrite(GPIO_PORTN_BASE,GPIO_PIN_0,0);
delay(period/2);
}

}

//delay function for accurate delay-
void delay(uint32_t num){

TimerIntClear(TIMER0_BASE,TIMER_TIMA_TIMEOUT);
TimerConfigure(TIMER0_BASE,TIMER_CFG_PERIODIC);
TimerLoadSet(TIMER0_BASE,TIMER_A,num-1);

TimerEnable(TIMER0_BASE, TIMER_A);
while(!TimerIntStatus(TIMER0_BASE,false)){

}




Thanks a lot for all of you .
Regards
Haroon

over 10 years ago

0 Chuck Davenport over 10 years ago

TI__Guru 59540 points

Haroon,

Have you tried a search of the E2E for other threads discussing similar issues? For example, this thread seems to be similar to what you are experiencing: e2e.ti.com/.../1821571

0 Chuck Davenport over 10 years ago in reply to Chuck Davenport

TI__Guru 59540 points

Haroon,

given you have started a new thread in place of the older one where you already have some inputs from other users willing to assist you, I will close this thread and defer to the other. Would appreciate if you could post your new code there so that those that have graciously offered to provide some help can continue to do so.

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LCD 12864 interface with TM4C1294 Launchpad