#include "pioLib.h" IMPORT DAADIO daadio; IMPORT PIO pio; void pioPoll (port, msgQId) int port; MSG_Q_ID msgQId; { PIO_MSG_Q_DATA msgQData; UINT8 currentState; UINT8 lastState[PIO_MAX_CHANNELS_PER_PORT]; int channel; IMPORT int errno; UINT8 * pOutputEnablePort; /* Error checking */ if (pio.initialized == FALSE) { printf ("pio not initialized\n"); return; } /* Fail if not an input port, i.e. if the corresponding bit in the output enable register is on */ pOutputEnablePort = (UINT8 *) daadio.baseAddr + PIO_OUTPUT_ENABLE_OFFSET; if (*pOutputEnablePort & (1 { printf ("Cannot poll an output port\n"); return; } /* Initialize our record of the last state of each channel to be OFF */ for (channel=0; channel lastState[channel] = OFF; FOREVER { /* check each channel in port */ for (channel=0; channel { /* Get the current state of the channel */ currentState = pioGet (port, channel); /* Check to see if the current state differs from the state of the channel the last time we checked. If it is, we need to generated a message. */ if (lastState[channel] != currentState) { /* Initialize the message structure and send it. */ msgQData.port = port; msgQData.channel = channel; msgQData.state = currentState; msgQData.timeStamp = tickGet(); if (msgQSend (msgQId, &msgQData, sizeof (PIO_MSG_Q_DATA), NO_WAIT, MSG_PRI_NORMAL) == ERROR) { /* If failure was because queue is full, just print warning and continue. Any other failure, print message and terminate. */ if (errno == S_objLib_OBJ_UNAVAILABLE) printf ("Msg Queue full: dumping data for port %d, channel %d, status is %s at clock tick %d\n", port, channel, (currentState) ? "ON" : "OFF", msgQData.timeStamp); else { printf ("Msg Queue fatal error: aborting poll task\n"); return; } } /* Update our record of the last state for this channel. */ lastState[channel] = currentState; } taskDelay (PIO_POLL_DELAY); } } }
