Revision 0:bc8591a28ec2, committed 2010-01-02

Comitter:

kevin

Date:

Sat Jan 02 18:05:33 2010 +0000

Commit message:

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sat Jan 02 18:05:33 2010 +0000
@@ -0,0 +1,131 @@
+#include "mbed.h"
+#include "TextLCD.h"
+// included in libmbed rev14
+#include "CAN.h"
+
+//enable additional serial debug messages
+//#define DEBUG_CAN_TX 1
+#define DEBUG_IR_RAW 1
+
+AnalogIn ain(p20);
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+TextLCD lcd(p14, p15, p16, p17, p18, p19, p21, 8);
+
+Ticker TickerSerialTx;
+Ticker TickerLcdUpdate;
+Ticker TickerCanTx;
+
+// conversion from IR sensor input voltage to nominal gas value
+#define CAN_GAS_MAX  4000
+#define CAN_GAS_MIN  700
+#define IR_MIN  0.28
+#define IR_MAX  0.76
+// 0.12 - 0.13   idle   update: seen 0.02 ..
+// 0.76          max
+
+// CAN defines
+#define CAN_ID_EGAS_CTRL   0x700
+#define CAN_DLC_EGAS_CTRL  1
+#define CAN_ID_EGAS_NOMINAL_VALUE   0x701
+#define CAN_DLC_EGAS_NOMINAL_VALUE  2
+#define CAN_BYTE_HIGH_EGAS_NOMINAL_VALUE  1
+#define CAN_BYTE_LOW_EGAS_NOMINAL_VALUE   0
+
+// CAN_RS pin at Philips PCA82C250 can bus controller.
+// activate transceiver by pulling this pin to GND.
+// (Rise and fall slope controlled by resistor R_s)
+// (+5V result in tranceiver standby mode)
+// For further information see datasheet page 4
+DigitalOut can_Pca82c250SlopePin(p28);
+// We use can on mbed pins 29(CAN_TXD) and 30(CAN_RXD).
+CAN can2(p30, p29);
+
+// value which will be sent via can
+unsigned short u16_CanGasNominal = CAN_GAS_MIN;
+// IR sensor value
+float f_IrDistance = 0.0;
+// 2 can objects for TX
+CANMessage can_MsgTx_EgasCtrl;
+CANMessage can_MsgTx_EgasNominalValue;
+
+
+void CanSendEgas() {
+    // idle
+    if ( (f_IrDistance > IR_MAX) || (f_IrDistance < IR_MIN) ) {
+        u16_CanGasNominal = CAN_GAS_MIN;
+    }
+    // valid input range
+    else {
+        u16_CanGasNominal = (unsigned short)( (((CAN_GAS_MAX-CAN_GAS_MIN)*(f_IrDistance-IR_MIN))/(IR_MAX-IR_MIN))+CAN_GAS_MIN );
+    }
+    // debug
+    //printf("u16_CanGasNominal: %d\n\r", u16_CanGasNominal);
+
+    if (can2.write(can_MsgTx_EgasCtrl)) {
+#ifdef DEBUG_CAN_TX
+        printf("CanTx--> id: 0x%x  dlc: %d  data: ", can_MsgTx_EgasCtrl.id, can_MsgTx_EgasCtrl.len);
+        for (char i=0; i<can_MsgTx_EgasCtrl.len; i++) {
+            printf("%x ", can_MsgTx_EgasCtrl.data[i]);
+        }
+        printf("\n\r");
+#endif
+    }
+
+    can_MsgTx_EgasNominalValue.data[CAN_BYTE_LOW_EGAS_NOMINAL_VALUE] = (unsigned char)(u16_CanGasNominal);
+    can_MsgTx_EgasNominalValue.data[CAN_BYTE_HIGH_EGAS_NOMINAL_VALUE] = (unsigned char)(u16_CanGasNominal>>8);
+    if (can2.write(can_MsgTx_EgasNominalValue)) {
+#ifdef DEBUG_CAN_TX
+        printf("CanTx--> id: 0x%x  dlc: %d  data: ", can_MsgTx_EgasNominalValue.id, can_MsgTx_EgasNominalValue.len);
+        for (char i=0; i<can_MsgTx_EgasNominalValue.len; i++) {
+            printf("%x ", can_MsgTx_EgasNominalValue.data[i]);
+        }
+        printf("\n\r");
+#endif
+    }
+
+}
+
+void SerialSendIrDistance() {
+    printf("f_IrDistance: %f\r\n", f_IrDistance);
+}
+
+void LcdPrintIrDistance() {
+    lcd.printf("IrDist: %f", f_IrDistance);
+}
+
+int main() {
+    // 500kbit/s
+    can2.frequency(500000);
+    // activate external can transceiver
+    can_Pca82c250SlopePin = 0;
+    // init everything
+    can_MsgTx_EgasCtrl.id = CAN_ID_EGAS_CTRL;
+    can_MsgTx_EgasCtrl.len = CAN_DLC_EGAS_CTRL;
+    can_MsgTx_EgasCtrl.data[0] = 1;
+    can_MsgTx_EgasNominalValue.data[CAN_BYTE_LOW_EGAS_NOMINAL_VALUE] = (unsigned char)(u16_CanGasNominal);
+    can_MsgTx_EgasNominalValue.data[CAN_BYTE_HIGH_EGAS_NOMINAL_VALUE] = (unsigned char)(u16_CanGasNominal>>8);
+    can_MsgTx_EgasNominalValue.id = CAN_ID_EGAS_NOMINAL_VALUE;
+    can_MsgTx_EgasNominalValue.len = CAN_DLC_EGAS_NOMINAL_VALUE;
+
+#ifdef DEBUG_IR_RAW
+    TickerSerialTx.attach(&SerialSendIrDistance, 0.35);
+#endif
+    TickerLcdUpdate.attach(&LcdPrintIrDistance, 0.75);
+    TickerCanTx.attach(&CanSendEgas, 0.1);
+
+    while (1) {
+        // get new distance from sensor
+        f_IrDistance = ain.read();
+
+        // show distance with the 4 leds
+        led1 = (f_IrDistance > 0.11) ? 1 : 0;
+        led2 = (f_IrDistance > 0.30) ? 1 : 0;
+        led3 = (f_IrDistance > 0.47) ? 1 : 0;
+        led4 = (f_IrDistance > 0.74) ? 1 : 0;
+    }
+}
+
+// TODO: no global variables
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Sat Jan 02 18:05:33 2010 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/a0336ede94ce