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Diffstat (limited to 'src/arch/msp430fr5994lp/driver/spi_b.cc')
-rw-r--r--src/arch/msp430fr5994lp/driver/spi_b.cc75
1 files changed, 75 insertions, 0 deletions
diff --git a/src/arch/msp430fr5994lp/driver/spi_b.cc b/src/arch/msp430fr5994lp/driver/spi_b.cc
new file mode 100644
index 0000000..0fa71da
--- /dev/null
+++ b/src/arch/msp430fr5994lp/driver/spi_b.cc
@@ -0,0 +1,75 @@
+#include "driver/spi_b.h"
+#include <msp430.h>
+
+#ifndef F_I2C
+#define F_I2C 1000000UL
+#endif
+
+void SPI::setup()
+{
+ UCB0CTLW0 |= UCSWRST;
+
+ /* UCB0CLK Pin 2.2 */
+ P2SEL0 &= ~BIT2;
+ P2SEL1 |= BIT2;
+ P2DIR |= BIT2;
+
+ /* UCB0SIMO Pin 1.6 */
+ P1SEL0 &= ~BIT6;
+ P1SEL1 |= BIT6;
+ P1DIR |= BIT6;
+
+ /* UCB0SOMI Pin 1.7 */
+ P1SEL0 &= ~BIT7;
+ P1SEL1 |= BIT7;
+ P1DIR &= ~BIT7;
+ //P1REN |= BIT6;
+
+ UCB0CTLW0 = UCCKPH | UCMSB | UCMST | UCSYNC | UCMODE_0 | UCSSEL__SMCLK | UCSWRST;
+ UCB0BRW = (F_CPU/F_I2C)-1; // /16 -> 1MHz
+ // UCB0BRW = (F_CPU / F_I2C) - 1
+ UCB0CTLW0 &= ~UCSWRST;
+}
+
+static inline unsigned char clean_rxbuf()
+{
+ return UCB0RXBUF;
+}
+
+signed char SPI::xmit(unsigned char tx_len, unsigned char *tx_buf,
+ unsigned char rx_len, unsigned char *rx_buf)
+{
+ if (tx_len < 1) {
+ return -1;
+ }
+
+ while (UCB0STATW & UCBUSY) ;
+
+ if (!(UCB0IFG & UCTXIFG)) {
+ return -1;
+ }
+
+ UCB0IFG &= ~UCRXIFG;
+ UCB0TXBUF = tx_buf[0];
+
+ unsigned char tx_pos = 1;
+ unsigned char rx_pos = 0;
+
+ while (tx_pos < tx_len || rx_pos < rx_len) {
+ if ((tx_pos < tx_len) && (UCB0IFG & UCTXIFG)) {
+ UCB0TXBUF = tx_buf[tx_pos++];
+ }
+ if (UCB0IFG & UCRXIFG) {
+ if (rx_pos < rx_len) {
+ rx_buf[rx_pos] = UCB0RXBUF;
+ } else {
+ UCB0IFG &= ~UCRXIFG;
+ }
+ rx_pos++;
+ }
+ }
+ while (UCB0STATW & UCBUSY) ;
+ return 0;
+}
+
+SPI spi;