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authorDaniel Friesel <derf@finalrewind.org>2017-12-14 15:51:11 +0100
committerDaniel Friesel <derf@finalrewind.org>2017-12-14 15:51:11 +0100
commit51a00f59ea9ecb49471b30921f36821fdfa75bc4 (patch)
tree4c237974cf044d5a7067aba48070ad7f6e3c7d11 /src/arch/msp430fr5969lp/driver/i2c.cc
parent693afffd7b89507916ecd759767b0b7e947dca60 (diff)
Add I2C and LM75 drivers
Diffstat (limited to 'src/arch/msp430fr5969lp/driver/i2c.cc')
-rw-r--r--src/arch/msp430fr5969lp/driver/i2c.cc92
1 files changed, 92 insertions, 0 deletions
diff --git a/src/arch/msp430fr5969lp/driver/i2c.cc b/src/arch/msp430fr5969lp/driver/i2c.cc
new file mode 100644
index 0000000..80f33b0
--- /dev/null
+++ b/src/arch/msp430fr5969lp/driver/i2c.cc
@@ -0,0 +1,92 @@
+#include "driver/i2c.h"
+#include <msp430.h>
+
+signed char I2C::setup()
+{
+ UCB0CTL1 = UCSWRST;
+ UCB0CTLW0 = UCMODE_3 | UCMST | UCSYNC | UCSSEL_2 | UCSWRST | UCCLTO_1;
+ UCB0BRW = 0xf00;
+ P1DIR &= ~(BIT6 | BIT7);
+ P1SEL0 &= ~(BIT6 | BIT7);
+ P1SEL1 |= BIT6 | BIT7;
+
+ UCB0CTL1 &= ~UCSWRST;
+ UCB0I2CSA = 0;
+
+ __delay_cycles(1600);
+
+ if (UCB0STAT & UCBBUSY)
+ return -1;
+
+ return 0;
+}
+
+void I2C::scan(unsigned int *results)
+{
+ for (unsigned char address = 0; address < 128; address++) {
+ UCB0I2CSA = address;
+ UCB0CTL1 |= UCTR | UCTXSTT | UCTXSTP;
+
+ while (UCB0CTL1 & UCTXSTP);
+
+ if (UCB0IFG & UCNACKIFG) {
+ UCB0IFG &= ~UCNACKIFG;
+ } else {
+ results[address / (8 * sizeof(unsigned int))] |= 1 << (address % (8 * sizeof(unsigned int)));
+ }
+ }
+ UCB0IFG = 0;
+}
+
+signed char I2C::xmit(unsigned char address,
+ unsigned char tx_len, unsigned char *tx_buf,
+ unsigned char rx_len, unsigned char *rx_buf)
+{
+ unsigned char i;
+ UCB0I2CSA = address;
+ if (tx_len) {
+ UCB0CTL1 |= UCTR | UCTXSTT;
+ for (i = 0; i < tx_len; i++) {
+ while (!(UCB0IFG & (UCTXIFG0 | UCNACKIFG | UCCLTOIFG)));
+ if (UCB0IFG & (UCNACKIFG | UCCLTOIFG)) {
+ UCB0IFG &= ~UCNACKIFG;
+ UCB0IFG &= ~UCCLTOIFG;
+ UCB0CTL1 |= UCTXSTP;
+ return -1;
+ }
+ UCB0TXBUF = tx_buf[i];
+ }
+ while (!(UCB0IFG & (UCTXIFG0 | UCNACKIFG | UCCLTOIFG)));
+ //if (UCB0IFG & (UCNACKIFG | UCCLTOIFG)) {
+ // UCB0IFG &= ~UCNACKIFG;
+ // UCB0IFG &= ~UCCLTOIFG;
+ // UCB0CTL1 |= UCTXSTP;
+ // return -1;
+ //}
+ }
+ if (rx_len) {
+ UCB0I2CSA = address;
+ UCB0IFG = 0;
+ UCB0CTL1 &= ~UCTR;
+ UCB0CTL1 |= UCTXSTT;
+
+ while (UCB0CTL1 & UCTXSTT);
+ UCB0IFG &= ~UCTXIFG0;
+
+ for (i = 0; i < rx_len; i++) {
+ if (i == rx_len - 1)
+ UCB0CTL1 |= UCTXSTP;
+ while (!(UCB0IFG & (UCRXIFG0 | UCNACKIFG | UCCLTOIFG)));
+ rx_buf[i] = UCB0RXBUF;
+ UCB0IFG &= ~UCRXIFG0;
+ }
+ UCB0IFG &= ~UCRXIFG0;
+ }
+
+ UCB0CTL1 |= UCTXSTP;
+
+ while (UCB0CTL1 & UCTXSTP);
+ return 0;
+}
+
+I2C i2c;