--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hp34comm.cpp Tue Sep 20 23:50:45 2016 +0200
@@ -0,0 +1,252 @@
+#include "hp34comm.h"
+#include "mbed.h"
+#include "CircularBuffer.h"
+
+/***** HP 34970A communication class ***/
+
+#define HP_SERIAL_TX PC_7 // serial6 RX
+#define HP_SERIAL_RX PA_1 // serial4 RX
+
+#ifdef DEBUG
+
+DigitalOut inrx(PC_0);
+DigitalOut intx(PC_1);
+DigitalOut ack(PC_3);
+DigitalOut staterx(PC_2);
+DigitalOut statetx(PH_1);
+
+#endif
+
+
+HPSerial::HPSerial():
+ ncmd(0),
+ serial_tx(NC, HP_SERIAL_TX), serial_rx(NC, HP_SERIAL_RX) {
+
+ //pc.printf("HPSerial init\n");
+
+ for(uint8_t i=0; i<MAX_ERRS; i++)
+ errs[i] = 0;
+ reset();
+
+ serial_tx.baud(187500);
+ serial_tx.attach(this, &HPSerial::txIrq, Serial::RxIrq); //sic!
+
+ serial_rx.baud(187500);
+ serial_rx.attach(this, &HPSerial::rxIrq, Serial::RxIrq);
+}
+
+bool HPSerial::cmd_available(void) {
+ return !cmdbuf.empty();
+}
+
+bool HPSerial::pop(CMD& cmd) {
+ return cmdbuf.pop(cmd);
+}
+
+bool HPSerial::cmd_buf_full(void) {
+ return cmdbuf.full();
+}
+
+unsigned int HPSerial::nerrors(uint8_t errorno) {
+ return errs[errorno];
+}
+
+
+
+void HPSerial::reset(uint8_t errorno) {
+ timeouter.detach();
+ head = 0;
+ tx_state = Idle;
+ setstatedbg();
+ tx_cmd = 0xFF;
+ tx_ack = false;
+ tx_len = 0xFF;
+ memset(buf, 0, BUF_SIZE);
+ if (errorno != 0xFF){
+ errs[errorno]++;
+ }
+
+}
+
+void HPSerial::handleAck(uint8_t val) {
+ if ((tx_state == Rx) & (tx_cmd == 0xFF) & (tx_ack == false) & (val == 0x66)) {
+ // special case: keypad does not acknwledge and takes precedence
+ // on the "bus"
+ tx_state = Tx;
+ setstatedbg();
+ } else
+
+ if (tx_ack == true)
+ reset(0);
+
+ else
+ if (tx_cmd == 0xFF) // still at the beginning of a packet, expect 0x99 as ack
+ if (val == 0x99)
+ {
+ tx_ack = true;
+#ifdef DEBUG
+ ack = 1;
+ wait_us(2);
+ ack = 0;
+#endif
+ }
+ else
+ reset(1);
+
+ else // expect 0x00 as ack
+ if (val == 0x00)
+ {
+ tx_ack = true;
+#ifdef DEBUG
+ ack = 1;
+ wait_us(2);
+ ack = 0;
+ wait_us(2);
+ ack = 1;
+ wait_us(2);
+ ack = 0;
+#endif
+ }
+ else
+ reset(2);
+}
+
+void HPSerial::pushCmd(TrState direction, uint8_t cmd, uint8_t size, char *payload) {
+ CMD val;
+ uint8_t i;
+ val.id = ncmd++;
+ val.direction = direction;
+ val.cmd = cmd;
+ val.size = size;
+ for(i=0; i<size; i++)
+ val.value[i] = payload[i];
+ val.value[i] = 0x00;
+ cmdbuf.push(val);
+}
+
+void HPSerial::handleChar(uint8_t val) {
+ if (tx_ack == false)
+ reset(3);
+ else // remaining of the state machine
+ if (tx_cmd == 0xFF) {
+ // begin of transmission, expect a cmd
+ tx_cmd = val;
+ tx_ack = false;
+ if (tx_state == Rx)
+ tx_len = 0xFF;
+ else
+ tx_len = 0x00; // no payload: tx_cmd is the key stroke
+ }
+ else if (tx_len == 0xFF) {
+ // got a cmd, expect a payload size
+ tx_len = val;
+ tx_ack = false;
+ }
+ else if (tx_len > 0) {
+ // a payload char
+ buf[head++] = val;
+ tx_len--;
+ tx_ack = false;
+ }
+ else { // end of payload, manage sent content
+ uint8_t cur_state = tx_state;
+ pushCmd(tx_state, tx_cmd, head, buf);
+
+ switch(val) {
+ case 0x66: // a new transmisson
+ reset();
+ tx_state = cur_state;
+ setstatedbg();
+ break;
+ case 0x55:
+ reset();
+ break;
+ default:
+ reset(6);
+ break;
+ }
+ }
+}
+
+
+
+void HPSerial::setstatedbg(void) {
+ /*
+ if (tx_state == Rx)
+ staterx = 1;
+ else
+ staterx = 0;
+ if (tx_state == Tx)
+ statetx = 1;
+ else
+ statetx = 0;
+ */
+}
+
+void HPSerial::rxIrq(void) {
+ uint8_t val;
+ if(serial_rx.readable()) { // no reason why we would end here without this condition, but hey
+#ifdef DEBUG
+ inrx=1;
+#endif
+ val = serial_rx.getc();
+
+ timeouter.attach(this, &HPSerial::timeout, 0.001); // if nothing else happen in the next ms, reset
+
+ if (tx_state == Idle)
+ if (val == 0x66) {
+ // no transmission in progress, expect a start of transmission
+ tx_state = Rx;
+ tx_ack = false;
+ setstatedbg();
+ }
+ else
+ reset(4);
+
+ else if (tx_state == Tx) // manage the acks
+ handleAck(val);
+
+ else
+ handleChar(val);
+#ifdef DEBUG
+ inrx=0;
+#endif
+ }
+}
+
+void HPSerial::txIrq(void) {
+ uint8_t val;
+ if(serial_tx.readable()) { // no reason why we would end here without this condition, but hey
+#ifdef DEBUG
+ intx=1;
+#endif
+ val = serial_tx.getc();
+
+ timeouter.attach(this, &HPSerial::timeout, 0.001); // if nothing else happen in the next ms, reset
+
+ if (tx_state == Idle)
+ if (val == 0x66) {
+ // no transmission in progress, expect a start of transmission
+ tx_state = Tx;
+ tx_ack = false;
+ setstatedbg();
+ }
+ else
+ reset(5);
+
+ else if (tx_state == Rx) // manage the acks
+ handleAck(val);
+
+ else
+ handleChar(val);
+ }
+#ifdef DEBUG
+ intx=0;
+#endif
+}
+
+void HPSerial::timeout(void) {
+ if (tx_state != Idle) {
+ reset(7);
+ }
+}