DownconverterFirmware/main.c
Marco Vitchi Thulin 81b93a2372 Correct documentation
Made som changes to docs and comments to be more accurate
2024-01-23 10:25:45 +01:00

122 lines
No EOL
3.3 KiB
C

#include<avr/io.h>
#include "common.h"
// XXX - ADF4350 LE
// PB2 - SCK to ADF4350 CLK
// PB1 - DO (MOSI) to ADF4350 DATA
// XXX - ADF4350 LD
String tosend="Test";
void Delay(uint32_t);
uint8_t SendReceiveSPIData(uint8_t);
void SendSPIDataADF4350 (uint32_t);
void spi_setup()
{
// set direction of PB1 (DO) and PB2 (USCK) as output
DDRB=(1<<PB1)|(1<<PB2);
// set to three wire mode (SPI)
USICR=(1<<USIWM0);
//USICR=(0<<USIWM1); not needed
}
int main()
{
// set instructions to configure the ADF4350 for a 1 GHz +5dBm output
uint32_t ar0=0x500000;
uint32_t ar1=0x8008011;
uint32_t ar2=0x4e42;
uint32_t ar3=0x4b3;
uint32_t ar4=0xac803c;
uint32_t ar5=0x580005;
// alternative instructions for a 1001.25 MHz +5dBm output
//uint32_t ar0=0x500008;
//uint32_t ar1=0x8008029;
//uint32_t ar2=0x4e42;
//uint32_t ar3=0x4b3;
//uint32_t ar4=0xac803c;
//uint32_t ar5=0x580005;
spi_setup();
}
// general purpose delay
void Delay(uint32_t tmax)
{
uint32_t i;
for (i=0;i < tmax ; i++)
{
asm("nop");
}
}
// send an 8 bit word via SPI1 and receive an 8 bit word at the same time
uint8_t SendReceiveSPIData(uint8_t value)
{
uint8_t lout = 0;
short int i=0;
for(i=0;i<=3;i++)
{
USIDR=value[i]; // write data bytes in Data register, will cause them to get sent on clock
while(USIOIF==0) // check USI data counter overflow flag to detect the end of transmission every byte
{
USICR|=(1<<USICLK)|(1<<USITC); // enable clock for transmission and generate clock for slave deivce
}
USISR|=(1<<USIOIF) // clear USI data counter overflow flag
}
// Read in a 16 bit frame (replace with proper reading response thing)
///uint16_t inbyte = *(uint32_t *)(SPI1_BASE + 0x0c);
while (lout == 0)
{
// do stuff to check response?
lout = 1;
// Read the SPI status register
///uint32_t statusSPI = *(uint32_t *)(SPI1_BASE + 0x08);
// Just bit 1 the transmit buffer empty flag - wait for this to go high then leave this function
/// &= BIT_1;
// The condition has been met so signal to get out of this loop
///if (statusSPI == BIT_1) lout = 1;
}
return inbyte;
}
// send a 32 bit register value to the ADF4350
void SendSPIDataADF4350 (uint32_t outval)
{
// split into 4 x 8-bit words
uint8_t byte1 = (outval & 0xFF000000) >> 24;
uint8_t byte2 = (outval & 0x00FF0000) >> 16;
uint8_t byte3 = (outval & 0x0000FF00) >> 8;
uint8_t byte4 = outval & 0x000000FF;
// send these to the ADF4350 via SPI
SendReceiveSPIData (byte1);
SendReceiveSPIData (byte2);
SendReceiveSPIData (byte3);
SendReceiveSPIData (byte4);
uint8_t lout = 0;
// Loop waiting for the the SPI BSY flag to go low
while (lout == 0)
{
// Read the SPI status register
uint32_t statusSPI = *(uint32_t *)(SPI1_BASE + 0x08);
// Just bit 7 the SPI BSY flag - wait for this to go low then leave this function
statusSPI &= BIT_7;
// The condition has been met so signal to get out of this loop
if (statusSPI == 0) lout = 1;
}
// Add a delay here so the clock has gone low before LE is taken high
Delay(10);
// Take LE high to load the data into the register
*(uint32_t *)(GPIOA_BASE + 0x10) = BIT_2;
// Short delay while LE is high (minimum of 20ns)
Delay(30);
// Take LE low again
*(uint32_t *)(GPIOA_BASE + 0x14) = BIT_2;
}