Jos van 't Hof
/
Eavesdropper
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Dependencies: FastIO FastPWM mbed
Revision 0:050184ab5c0d, committed 2014-09-02
- Comitter:
- Josvth
- Date:
- Tue Sep 02 08:20:13 2014 +0000
- Commit message:
- Commit!
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/FastIO.lib Tue Sep 02 08:20:13 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/Sissors/code/FastIO/#b0d725519c4f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/FastPWM.lib Tue Sep 02 08:20:13 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/Sissors/code/FastPWM/#cdefd9d75b64
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Tue Sep 02 08:20:13 2014 +0000
@@ -0,0 +1,131 @@
+#include "mbed.h"
+#include "FastIO.h"
+#include "FastPWM.h"
+
+FastOut<LED1> led;
+
+//Pin 29 and 30 are connected to pin 21
+FastIn<p29> CAP_2_1_input;
+FastIn<p30> CAP_2_0_input;
+FastPWM pwm(p21);
+
+
+Serial pc(USBTX, USBRX); // tx, rx
+
+#define TIM2CR0 LPC_TIM2->CR0
+#define TIM2CR1 LPC_TIM2->CR1
+
+//void _cap_2_1_falling() {
+ // pc.printf("Interrupt: %X\n", LPC_TIM2->IR);
+ //led = 1;
+//}
+
+int main()
+{
+
+ unsigned int ticks = 226;
+
+ // This signal should give a manchester encoded 101010101
+ pwm.period_ticks(ticks);
+ pwm.pulsewidth_ticks(ticks / 2);
+
+ // Setup TIM2
+
+ // SC
+ LPC_SC->PCONP |= (1<<22); // Power on the Timer2
+ LPC_SC->PCLKSEL1 &= ~(3<<12); // Select CCLK/4 for TIM2 (whipes previous clock setting)
+ LPC_SC->PCLKSEL1 |= (1<<12); // Select CCLK for TIM2
+
+ // CCR
+ LPC_TIM2->CCR |= (3 << 1); // Set CAP2.0 on falling edge with interrupt
+ LPC_TIM2->CCR |= (1 << 3); // Set CAP2.1 on rising edge
+
+ pc.printf("CCR: %X\n", LPC_TIM2->CCR);
+
+ // TCR
+ LPC_TIM2->TCR = 0x0002; // Reset TIM2
+ LPC_TIM2->TCR = 0x0001; // Enable TIM2
+
+ bool buffer [16];
+ int bits = 0;
+
+ //NVIC_DisableIRQ(TIMER2_IRQn);
+ //NVIC_SetVector(TIMER2_IRQn, (uint32_t)&_cap_2_1_falling);
+ //NVIC_EnableIRQ(TIMER2_IRQn);
+
+ while(1) {
+
+ //pc.printf("Interrupt: %X\n", LPC_TIM2->IR);
+
+ // Poll CRO (falling edge) intterupt
+ if (LPC_TIM2->IR & (1 << 4)) {
+
+ led = 1;
+
+ wait(100);
+
+ led = 0;
+
+ int diff = (TIM2CR0 - TIM2CR1) % 0xFFFFFFFF;
+
+ if (diff > 90 && diff < 136) { // Check if diff is equal to T=1/848kHz with 20% error
+ // bit transition
+
+ if (bits == 0) { // Start of sequence
+ buffer[0] = 1;
+ } else {
+ buffer[bits] = !buffer[bits-1];
+ }
+
+ pc.printf("Trasition: %u\n", diff);
+
+ } else if (diff > 45 && diff < 68) { // Check if diff is equal to T/2
+ // repeat last bit
+
+ if (bits == 0) { // Start of sequence
+ buffer[0] = 1;
+ } else {
+ buffer[bits] = buffer[bits-1];
+ }
+
+ pc.printf("Repeat: %u\n", diff);
+
+ } else {
+ // error, default to 1
+ pc.printf("Error: %u\n", diff);
+ }
+
+ bits = bits + 1 % 16;
+
+ LPC_TIM2->IR |= (1 << 4); // Clear IR by writing a one
+
+ }
+
+// if (bits == 0) {
+//
+// for (int i = 0; i< 16; i++) {
+// pc.printf("%u", (int) buffer[i]);
+// }
+//
+// pc.printf("\n");
+//
+// }
+
+// // Poll CRO (rising edge) intterupt
+// if (LCP_TIM2-IR != (1 << 5)) {
+//
+// int diff = (TIM2CR1 - TIM2CR2) % 0xFFFFFFFF;
+//
+// // Do checks
+//
+// // End checks
+//
+//
+// LCP_TIM2->IR &= ~(1 << 5);
+// }
+
+
+
+ }
+
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Tue Sep 02 08:20:13 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/9327015d4013 \ No newline at end of file