timcam
Newbie level 1

Reference Previous Thread: https://www.edaboard.com/threads/219637/
Hello RuH_iranga,
Thank you for posting this code. It is very helpful in understanding the PIC spi UART.
I am confused in how we can read more than one byte. Suppose we want to read 16 bits. The data sheet says the buffer holds 8 bits.
Ho do we get the next byte?
Regards,
Tim
Hello RuH_iranga,
Thank you for posting this code. It is very helpful in understanding the PIC spi UART.
I am confused in how we can read more than one byte. Suppose we want to read 16 bits. The data sheet says the buffer holds 8 bits.
Code:
if(SSPSTAT.BF)
{
gdata=SSPBUF;
SSPCON.SSPOV=0;
}
Ho do we get the next byte?
Regards,
Tim
Hi all
This code is working on Proteus as well as tested on 18F452 (Master) and 16F877a (Slave).
Compiler- MikroC
I tried this one several times but it didn't work. When I changed the inbuilt "Spi_read()" command and used direct Registry reading as in the data sheet. Then it worked.
Master
Code:// Mikroc codes for SPI master device void main() { INTCON.GIE = 1; //ADCON1=0b00000111; trisc=0b00010000; trisd=0b00000000; //trisa=0b00000000; portd.f1=1; SSPSTAT.SMP=0; SSPSTAT.CKE=0; SSPCON.SSPEN=1; SSPCON.CKP=1; SSPCON.SSPM3=0; SSPCON.SSPM2=0; SSPCON.SSPM1=0; SSPCON.SSPM0=0; //Spi_Init_Advanced(MASTER_OSC_DIV4, DATA_SAMPLE_END, CLK_Idle_HIGH, LOW_2_HIGH); while(1) { portd.f1=0; SSPCON.WCOL=0; Spi_Write(102); portd.f1=1; portd.f2=0; SSPCON.WCOL=0; Spi_Write(254); delay_ms(100); portd.f2=1; portd.f2=0; SSPCON.WCOL=0; Spi_Write(1); delay_ms(100); portd.f2=1; } }
Slave
Code:// Mikroc codes for SPI slave divice // SIMULATION SUCCEED DSN IN My Doc PLATFORM FOLDER void main() { unsigned int buffer, gdata =0; trisa=0b00100000; trisc=0b00011000; trisd=0b00000000; trisb=0b00000000; INTCON.GIE = 1; SSPSTAT.SMP=0; SSPSTAT.CKE=0; //SSPCON.SSPOV=0; SSPCON.SSPEN=1; SSPCON.CKP=1; SSPCON.SSPM3=0; SSPCON.SSPM2=1; SSPCON.SSPM1=0; SSPCON.SSPM0=0; //Spi_Init_Advanced(SLAVE_SS_ENABLE,DATA_SAMPLE_END,CLK_Idle_HIGH,LOW_2_HIGH); while(1) { if(SSPSTAT.BF) { gdata=SSPBUF; SSPCON.SSPOV=0; } // gdata=Spi_Read(0); if(gdata>100) { portb.f6=1; portb.f7=0; //delay_ms(20); } else { portb.f6=0; portb.f7=1; //delay_ms(20); } } }
Slave 2
Code:// Mikroc codes for SPI slave divice // SIMULATION SUCCEED DSN IN My Doc PLATFORM FOLDER void main() { unsigned int buffer, gdata =0; trisa=0b00100000; trisc=0b00011000; trisd=0b00000000; trisb=0b00000000; INTCON.GIE = 1; SSPSTAT.SMP=0; SSPSTAT.CKE=0; //SSPCON.SSPOV=0; SSPCON.SSPEN=1; SSPCON.CKP=1; SSPCON.SSPM3=0; SSPCON.SSPM2=1; SSPCON.SSPM1=0; SSPCON.SSPM0=0; //Spi_Init_Advanced(SLAVE_SS_ENABLE,DATA_SAMPLE_END,CLK_Idle_HIGH,LOW_2_HIGH); while(1) { if(SSPSTAT.BF) { gdata=SSPBUF; SSPCON.SSPOV=0; } // gdata=Spi_Read(0); //if(gdata>103) //{ portb=gdata; //portb.f6=0; //portb.f7=1; //delay_ms(20); //} //else //{ // portb.f6=1; // portb.f7=0; //delay_ms(20); // } } }
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