USCI I2C support.

[tinyos-2.x.git] / tos / chips / msp430 / usci / HplMsp430UsciInt1P.nc

diff --git a/tos/chips/msp430/usci/HplMsp430UsciInt1P.nc b/tos/chips/msp430/usci/HplMsp430UsciInt1P.nc
index 45eada48e2e7a5972823b945deef99492b28311d..1e18eb70bf9605c83845b19f4e219bb2a557b63b 100644 (file)
--- a/tos/chips/msp430/usci/HplMsp430UsciInt1P.nc
+++ b/tos/chips/msp430/usci/HplMsp430UsciInt1P.nc
@@ -100,7 +100,11 @@ implementation
    */
   TOSH_SIGNAL(USCIAB1TX_VECTOR) {
     if (READ_FLAG(UC1IFG & UC1IE, UCB1RXIE))
-      signal IntB.rx(UCB1RXBUF); /* I2C receive */
+      /* I2C receive.  Do not read UCB1RXBUF here, as the code receiving
+       * IntB.rx() may first need to set stop and/or start bits.  The receiver
+       * must read UCB1RXBUF.
+       */
+      signal IntB.rx(0);
     else if (READ_FLAG(UC1IFG & UC1IE, UCA1TXIFG))
       signal IntA.tx();
     else if (READ_FLAG(UC1IFG & UC1IE, UCB1TXIFG))