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#include <xc.h>
#include <stdint.h>
#include "system.h"
#include "types.h"
#include "spi.h"
#include "dac.h"
// Configuration bits:
// buffered, gain=1x, mode=active
typedef enum {
CONFA = 0x7000, // DAC A
CONFB = 0xF000, // DAC B
} Conf;
void
dacInit(void) {
DAC1_CS_TRIS = OUT;
DAC2_CS_TRIS = OUT;
DAC1_CS = 1;
DAC2_CS = 1;
U16 level = 0u;
dacSet1a(level);
dacSet1b(level);
dacSet2a(level);
dacSet2b(level);
}
static void
set(U8 dacNum, Conf conf, U16 level) {
level <<= 2u; // D0 at bit 2
level = ((U16)conf & 0xF000) | (level & 0x0FFF); // set config bits
if (dacNum == 1u) {
DAC1_CS = 0;
} else {
DAC2_CS = 0;
}
_delay(1);
(void)spiTx((level>>8u) & 0xFF); // MSB
(void)spiTx((level>>0u) & 0xFF); // LSB
if (dacNum == 1u) {
DAC1_CS = 1;
} else {
DAC2_CS = 1;
}
}
void
dacSet1a(U16 level) {
set(1u, CONFA, level);
}
void
dacSet1b(U16 level) {
set(1u, CONFB, level);
}
void
dacSet2a(U16 level) {
set(2u, CONFA, level);
}
void
dacSet2b(U16 level) {
set(2u, CONFB, level);
}
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