spi and eeprom modules

1 files changed, 30 insertions, 0 deletions

diff --git a/sw/spi.c b/sw/spi.c
new file mode 100644
index 0000000..1793c4d
--- /dev/null
+++ b/sw/spi.c
@@ -0,0 +1,30 @@
+#include <xc.h>
+
+#include <stdint.h>
+
+#include "sys.h"
+#include "types.h"
+
+#include "spi.h"
+
+void
+spiInit(void) {
+	U8 junk;
+
+	TRISBbits.TRISB4 = IN; // SDI
+	TRISCbits.TRISC7 = OUT; // SDO
+	TRISBbits.TRISB6 = OUT; // SCK
+
+	SSPSTAT = 0x00;
+	SSPCON1 = 0x01; // FOSC/16 => 3MHz SPI clock
+	SSPCON1bits.SSPEN = 1; // enable
+	junk = SSPBUF; // dummy read to clear BF
+	(void)junk;
+}
+
+U8
+spiTx(U8 c) {
+	SSPBUF = c;
+	while (!SSPSTATbits.BF) {}
+	return SSPBUF;
+}