Troubleshooting Help NHD-0420CW-AR3
I have a NHD-0420CW-AR3. I am programming it with a PIC24 using the SPI bus, powered using 3.3v. I have determined that I can talk to the device because I can successfully receive the ID byte with two consecutive reads of the Busy Flag/Part ID command.
My issue is that the screen is just plain dark.
Is there anything I can do to trouble shoot what might be going on?
Is there some sort of test mode that can be initiated?
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Would it be possible to get a pin-out diagram, along with your initialization routine?
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Glad to. I've attached the test circuit I used to connect up the screen and the MPLABX code for the PIC24.
#include <stdio.h>
#include <stdlib.h>
#include <xc.h>
#include <p24FJ128GA010.h>
_CONFIG2(FNOSC_PRIPLL & POSCMOD_XT) // Primary XT OSC with 4x PLL
_CONFIG1(JTAGEN_OFF & FWDTEN_OFF) // JTAG OFF and WatchDog Off
static const unsigned char acReverseByte[] = {
0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff};
void InitializeSPI2()
{
int iData;
//SPI2 Config
IEC2bits.SPI2IE=0; //interupt off
SPI2STATbits.SPIEN=0; //spi disable
IFS2bits.SPI2IF=0; //clear spi interupt flag
SPI2CON1bits.DISSCK=0; //Internal clock is enabled
SPI2CON1bits.DISSDO=0; //SDO pin is controlled by module
SPI2CON1bits.MODE16=0; //8 bit mode
SPI2CON1bits.SMP=0; //Sampled at middle of data output time
SPI2CON1bits.CKE=0; //Serial output data changes on transition from Idle clock state to active clock state (see bit 6)
//SPI2CON1bits.CKE=1; //Serial output data changes on transition from Idle clock state to active clock state (see bit 6)
SPI2CON1bits.SSEN=0; //SSx pin not used by module, pin controlled by port function
SPI2CON1bits.CKP=0; //Idle state for clock is a low level; active state is a high level
//pin setup
TRISGbits.TRISG8=0; //SDO2 output
LATGbits.LATG8=0;
TRISGbits.TRISG7=1; //SDI2 input
TRISGbits.TRISG6=0; //SCL2 input
LATGbits.LATG6=0;
TRISGbits.TRISG0=0; //Display reset
LATGbits.LATG0=0;
LATGbits.w=1;
TRISGbits.TRISG1=0; //Display Chip Select
SPI2CON1bits.MSTEN=1; //Master mode
//SPI2CON1bits.MSTEN=0; //Slave mode
SPI2CON1bits.SPRE=4; //Secondary prescale 4
SPI2CON1bits.PPRE=1; //Primary prescale 16:1
SPI2CON2bits.FRMEN=0; //Framed SPIx support disabled
SPI2STATbits.SPIROV=0; //No overflow
SPI2STATbits.SPIEN=1; //spi enable
iData = SPI2CON1; //save config for debug
}
void SendCommand(char cCommand)
{
int iRecieve1;
int iRecieve2;
int iRecieve3;
int iSendLow;
int iSendHigh;
//verify that display is free
LATGbits.LATG1=0;
while(SPI2STATbits.SPITBF!=0); //wait for spi2 transmit buffer to be open
do
{
SPI2BUF = 0xfc; //11111 r/w=1 dc=0 0
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve1 = SPI2BUF;
SPI2BUF = 0x00;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve2 = SPI2BUF;
} while (iRecieve2 & 0x80 != 0x80);
//send command
SPI2BUF = 0xf8; //11111 r/w=0 dc=0 0
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve1 = SPI2BUF;
iSendLow = acReverseByte[(int) cCommand];
iSendHigh = (iSendLow << 4) & 0xf0;
iSendLow = iSendLow & 0xf0;
SPI2BUF = iSendLow;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve2 = SPI2BUF;
SPI2BUF = iSendHigh;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve3 = SPI2BUF;
LATGbits.LATG1=1;
}
void SendData(char cData)
{
int iRecieve1;
int iRecieve2;
int iRecieve3;
int iSendLow;
int iSendHigh;
//verify that display is free
LATGbits.LATG1=0;
while(SPI2STATbits.SPITBF!=0); //wait for spi2 transmit buffer to be open
do
{
SPI2BUF = 0xfc; //11111 r/w=1 dc=0 0
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve1 = SPI2BUF;
SPI2BUF = 0x00;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve2 = SPI2BUF;
} while (iRecieve2 & 0x80 != 0x80);
//send command
SPI2BUF = 0xfe; //11111 r/w=1 dc=1 0
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve1 = SPI2BUF;
iSendLow = acReverseByte[(int)cData];
iSendHigh = (iSendLow << 4) & 0xf0;
iSendLow = iSendLow & 0xf0;
SPI2BUF = iSendLow;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve2 = SPI2BUF;
SPI2BUF = iSendHigh;
while(SPI2STATbits.SPIRBF==0); //wait for spi2 recieve buffer to show complete
iRecieve3 = SPI2BUF;
LATGbits.LATG1=1;
}
/*
*
*/
int main(int argc, char** argv) {
int iLoop;
TRISAbits.TRISA0 = 0;
TRISAbits.TRISA1 = 0;
TRISAbits.TRISA2 = 0;
TRISAbits.TRISA3 = 0;
TRISAbits.TRISA4 = 0;
TRISAbits.TRISA5 = 0;
TRISAbits.TRISA6 = 0;
TRISAbits.TRISA7 = 0;
InitializeSPI2();
SendCommand(0x2A); //function set (extended command set)
SendCommand(0x71); //function selection A
SendData(0x00); // disable internal VDD regulator (2.8V I/O). data(0x5C) = enable regulator (5V I/O)
SendCommand(0x28); //function set (fundamental command set)
SendCommand(0x08); //display off, cursor off, blink off
SendCommand(0x2A); //function set (extended command set)
SendCommand(0x79); //OLED command set enabled
SendCommand(0xD5); //set display clock divide ratio/oscillator frequency
SendCommand(0x70); //set display clock divide ratio/oscillator frequency
SendCommand(0x78); //OLED command set disabled
SendCommand(0x09); //extended function set (4-lines)
SendCommand(0x06); //COM SEG direction
SendCommand(0x72); //function selection B
SendData(0x00); //ROM CGRAM selection
SendCommand(0x2A); //function set (extended command set)
SendCommand(0x79); //OLED command set enabled
SendCommand(0xDA); //set SEG pins hardware configuration
SendCommand(0x10); //set SEG pins hardware configuration
SendCommand(0xDC); //function selection C
SendCommand(0x00); //function selection C
SendCommand(0x81); //set contrast control
SendCommand(0x7F); //set contrast control
SendCommand(0xD9); //set phase length
SendCommand(0xF1); //set phase length
SendCommand(0xDB); //set VCOMH deselect level
SendCommand(0x40); //set VCOMH deselect level
SendCommand(0x78); //OLED command set disabled
SendCommand(0x28); //function set (fundamental command set)
SendCommand(0x01);
SendCommand(0x02); //return home
for(iLoop=0;iLoop<20;iLoop++)
{
SendData(0x1F); //write solid blocks
}
return (EXIT_SUCCESS);
}0
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