1 files changed, 48 insertions, 0 deletions
diff --git a/rf_test/spi.c b/rf_test/spi.c
new file mode 100644
index 0000000..282cdce
--- /dev/null
+++ b/rf_test/spi.c
@@ -0,0 +1,48 @@
+#include <avr/io.h>
+
+#include "spi.h"
+
+#define SS_PIN   PB2
+#define SS_DDR   DDRB
+#define SS_PORT  PORTB
+
+void spi_init(void)
+{
+	SS_DDR |= (1 << SS_PIN);
+	SS_PORT |= (1 << SS_PIN);
+
+	DDR_SPI = (1 << DD_MOSI) | (1 << DD_SCK);
+	SPCR    = (1 << SPE) | (1 << MSTR) | (1 << SPR0);
+}
+
+uint8_t spi_send(uint8_t data)
+{
+	SS_PORT |= (1 << SS_PIN);
+
+	SPDR = data;
+	while (!(SPSR & (1 << SPIF)))
+		;
+	data = SPDR;
+
+	SS_PORT &= ~(1 << SS_PIN);
+
+	return data;
+}
+
+uint8_t spi_send(uint8_t addr, uint8_t data)
+{
+	SS_PORT |= (1 << SS_PIN);
+
+	SPDR = addr;
+	while (!(SPSR & (1 << SPIF)))
+		;
+
+	SPDR = data;
+	while (!(SPSR & (1 << SPIF)))
+		;
+
+	SS_PORT &= ~(1 << SS_PIN);
+
+	return data;
+}
+