* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
-
+
/**
* Uart implementation using a USCI device.
*
* TODO: Implement blocking like in Msp430UartSpiP.nc.
* Implement error checking via UCAxSTAT.
*
- * @author R. Steve McKown <smckown@gmail.com>
+ * @author R. Steve McKown <rsmckown@gmail.com>
*/
-
+
generic module Msp430UartP() {
provides {
interface UartStream;
}
}
implementation {
- #define saveBits(pin, pos, dir, out, ren) { \
- if (call pin.isOutput()) \
- dir |= (1 << pos); \
- if (call pin.getOut()) \
- out |= (1 << pos); \
- if (call pin.isRen()) \
- ren |= (1 << pos); \
- }
-
- #define restoreBits(pin, pos, dir, out, ren) { \
- if (ren & (1 << pos)) \
- call pin.enableRen(); \
- else \
- call pin.disableRen(); \
- if (out & (1 << pos)) \
- call pin.set(); \
- else \
- call pin.clr(); \
- if (dir & (1 << pos)) \
- call pin.makeOutput(); \
- else \
- call pin.makeInput(); \
- }
-
- /* Pin IO configuration storage for later restoration */
- uint8_t m_dir;
- uint8_t m_out;
- uint8_t m_ren;
+ enum {
+ /* Bit positions in m_pins */
+ PINS_RXD = 0,
+ PINS_TXD
+ };
+ uint8_t m_pins;
uint8_t* m_sobuf; /* Original buffer ptr from UartStream.send() */
- uint8_t m_solen; /* Original buffer len from UartStream.send() */
+ uint16_t m_solen; /* Original buffer len from UartStream.send() */
uint8_t* m_sbuf; /* Position of next char to send */
- uint8_t m_slen; /* Len of chars in m_sbuf to send */
+ uint16_t m_slen; /* Len of chars in m_sbuf to send */
bool m_rxie; /* Set if rxie has been enabled to UartStream.receive() */
uint8_t* m_robuf; /* Original receive buffer */
- uint8_t m_rolen; /* Original (maximum) receive len */
+ uint16_t m_rolen; /* Original (maximum) receive len */
uint8_t* m_rbuf; /* Position of next byte in which to receive a char */
- uint8_t m_rlen; /* Remaining length in receive buffer */
+ uint16_t m_rlen; /* Remaining length in receive buffer */
sfrb(MYBRX, 219U);
else
call Registers.clrStat(UCLISTEN);
- /* Save pin IO configuration */
- m_dir = m_out = m_ren = 0;
- saveBits(RXD, 0, m_dir, m_out, m_ren);
- saveBits(TXD, 1, m_dir, m_out, m_ren);
-
- /* Configure RX pin for UART use */
- call RXD.makeInput();
- if (config->ren & USCI_REN_RX) {
- if (config->ren & USCI_REN_RX_PULLUP)
- call RXD.set();
- else
- call RXD.clr();
- call RXD.enableRen();
+ /* Configure pins for UART, saving prior pin states */
+ m_pins = 0;
+ if (call RXD.isIOFunc()) {
+ m_pins |= (1 << PINS_RXD);
+ call RXD.selectModuleFunc();
}
- call RXD.selectModuleFunc();
-
-#if 0 /* pull-ups don't make sense on TXD, since it doesn't appear that
- * enabling an open-drain emulation mode via USCI is not possible.
- */
-
- /* Configure TX pin for UART use */
- if (config->ren & USCI_REN_TX) {
- if (config->ren & USCI_REN_TX_PULLUP)
- call TXD.set();
- else
- call TXD.clr();
- call TXD.enableRen();
+ if (call TXD.isIOFunc()) {
+ m_pins |= (1 << PINS_TXD);
+ call TXD.selectModuleFunc();
}
- call TXD.selectModuleFunc();
-#endif
+
+ /* Reset important state variables */
+ m_robuf = 0;
+ m_sobuf = 0;
/* Clear interrupts; we'll add them as needed */
call Registers.clrIeRx();
/* Enable the device */
call Registers.clrCtl1(UCSWRST);
+
+ /* TOS convention is for receive interrupts on by default. */
+ call Registers.clrIfgRx();
+ call Registers.setIeRx();
}
}
{
atomic {
/* Disable the device */
- call Registers.setCtl1(UCSYNC);
+ call Registers.setCtl1(UCSWRST);
/* Clear interrupts and interrupt flags */
call Registers.clrIeRx();
call Registers.clrIeTx();
call Registers.clrIfgRx();
- call Registers.clrIfgTx();
- /* Restore pins to their preconfigured state */
-#if 0
- restoreBits(RXD, 0, m_dir, m_out, m_ren);
- restoreBits(TXD, 0, m_dir, m_out, m_ren);
-#endif
- call RXD.selectIOFunc();
- call TXD.selectIOFunc();
+ /* Reset important state variables */
+ m_robuf = 0;
+ m_sobuf = 0;
+
+ /* Restore pins to their pre-configure state */
+ if (m_pins & (1 << PINS_RXD))
+ call RXD.selectIOFunc();
+ if (m_pins & (1 << PINS_TXD))
+ call TXD.selectIOFunc();
}
}
async command error_t UartByte.send(uint8_t byte)
{
- /* FIXME: race with UartStream.send() */
atomic {
- if (m_sobuf)
- return FAIL;
while (!call Registers.getIfgTx());
call Registers.setTxbuf(byte);
return SUCCESS;
atomic {
if (m_sobuf || !buf || !len)
return FAIL;
- m_sobuf = buf;
- m_solen = len;
+ m_sbuf = m_sobuf = buf;
+ m_slen = m_solen = len;
call Registers.setIeTx();
- call Registers.setTxbuf(*m_sobuf);
- m_slen = m_solen - 1;
- if (m_slen)
- m_sbuf = m_sobuf + 1;
return SUCCESS;
}
}
async event void Interrupts.tx()
{
- while (m_slen && call Registers.getIfgTx()) {
- call Registers.setTxbuf(*m_sbuf);
- if (--m_slen)
- m_sbuf++;
- }
- if (m_slen == 0 && m_sobuf) {
- call Registers.clrIeTx();
- call Registers.clrIfgTx();
- m_sobuf = 0;
- signal UartStream.sendDone(m_sobuf, m_solen, SUCCESS);
+ /* FIXME: this can cause an arbitrarily long ISR, if m_slen is large.
+ * But depending on timing, we may always only write 1 byte.
+ */
+ if (m_sobuf) {
+ while (!call Registers.getIfgTx()); /* in case interleaved UB.send */
+ while (m_slen && call Registers.getIfgTx()) {
+ call Registers.setTxbuf(*m_sbuf);
+ if (--m_slen)
+ m_sbuf++;
+ }
+ if (m_slen == 0) {
+ call Registers.clrIeTx();
+ m_sobuf = 0;
+ signal UartStream.sendDone(m_sobuf, m_solen, SUCCESS);
+ }
}
}
async event void Interrupts.rx(uint8_t byte)
{
- atomic {
- if (m_robuf) {
- /* receive() takes precedence if active */
- while (m_rlen && call Registers.getIfgRx()) {
- *m_rbuf = byte;
- if (--m_rlen)
- m_rbuf++;
- }
- if (m_rlen == 0 && m_robuf) {
- if (m_rxie) {
- call Registers.clrIeRx();
- call Registers.clrIfgRx();
- }
- m_robuf = 0;
- signal UartStream.receiveDone(m_robuf, m_rolen, SUCCESS);
+ if (m_robuf) {
+ /* receive() takes precedence if active */
+ /* FIXME: an arbitrarily long ISR may occur if m_rlen is large.
+ * But depending on timing, we may always only read 1 byte.
+ */
+ while (m_rlen && call Registers.getIfgRx()) {
+ *m_rbuf = byte;
+ if (--m_rlen)
+ m_rbuf++;
+ }
+ if (m_rlen == 0 && m_robuf) {
+ if (m_rxie) {
+ call Registers.clrIeRx();
+ call Registers.clrIfgRx();
}
- } else
- signal UartStream.receivedByte(byte);
- }
+ m_robuf = 0;
+ signal UartStream.receiveDone(m_robuf, m_rolen, SUCCESS);
+ }
+ } else
+ signal UartStream.receivedByte(byte);
}
default async command const msp430_usci_uart_t* Configure.get()
{
- const static msp430_usci_uart_t def = {
+ const static msp430_usci_uart_t def = {
ctl0: UCMODE_0, /* async, lsb first, 8N1 */
ctl1: UCSWRST | UCSSEL_3, /* clock uart from SMCLK */
brx: UBRX_1MHZ_115200,
projects / tinyos-2.x.git / blobdiff