diff options
Diffstat (limited to 'src/arch/msp430fr5969lp/driver/i2c.cc')
-rw-r--r-- | src/arch/msp430fr5969lp/driver/i2c.cc | 92 |
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; |