www.pudn.com > EM4469firmware.zip > main.c
/*
*-------------------------------------------------------------------------------
*-- RCSId: $Id: main.c,v 0.17 2003-10-10 10:55:40+02 mjg Exp mjg $
*-- $Name: $
*-------------------------------------------------------------------------------
*-- main.c (level1)
*-------------------------------------------------------------------------------
*-- $Log: main.c,v $
*-- Revision 0.17 2003-10-10 10:55:40+02 mjg
*-- *** empty log message ***
*--
*-- Revision 0.16 2003-08-21 16:00:21+02 mjg
*-- RTF capture problem
*--
*-- Revision 0.15 2003-08-20 10:53:20+02 mjg
*-- to redesign SearchPattern
*--
*-- Revision 0.14 2003-08-20 10:00:46+02 mjg
*-- to add debug features
*--
*-- Revision 0.13 2003-08-07 08:01:30+02 mjg
*-- *** empty log message ***
*--
*-- Revision 0.11 2003-07-22 13:27:48+02 mjg
*-- cloned firmware
*--
*-------------------------------------------------------------------------------
*/
#include
#include
#include
#include
#include
#include
#include
#include "level4.h"
#include "level3.h"
#include "level2.h"
// ==================================================================
// capture variables
uint8_t halfDataRate; //half period data rate modul
uint8_t counter1set; //counter1 settings
uint8_t lwr; //last word read
uint8_t delayed; //delayed value
uint8_t forward_link_type; //forward link modulation type
uint8_t decode_number; //decoder routine number
void (*decode)(void); //decoder routine variable
uint8_t enable_capture; //enable capture (0=disable, 1=capture enable, 2=debug pulse capture)
uint16_t last_capture; //counter1 is now reset at capture start, we make a difference
//between current and last value
uint8_t currentMaxTimeHi; //actual hi value of maximum capture time
uint8_t watchdog_reset; //watchdog activated
// ==================================================================
// level 1 local variables
register uint8_t captured_byte asm ("r6"); //store_bit current capture bits
register uint8_t captured_valid asm ("r7"); //store_bit current capture valid bits
register uint8_t capture_cnt asm ("r8"); //store_bit current capture byte index
register uint8_t captured_bit_count asm ("r9"); //store_bit current capture bit counter
uint8_t bit_pos; //bit position in demodulation
uint8_t last_bit; //for biphase and miller usage
uint8_t edge; //for manchester usage
uint8_t last_valid; //last valid value for invalid sequence compression
uint8_t treshold_0;
uint8_t treshold_1;
// ==================================================================
// function declarations
// ==================================================================
void avr_ini(void)
{
// ---------------------------------------------------------------
// UART initialization
// ---------------------------------------------------------------
UARTIni(); // level4 uart init routine
// ---------------------------------------------------------------
// 16-bit Timer/Counter1 initialization
// ---------------------------------------------------------------
TCCR1A = 0; // no compare otuput, no PWM mode ...
TCCR1B = (1<255) store_pulse(255); else store_pulse((uint8_t)capt);
}
y = 0;
(uint8_t)capt += halfDataRate >> 2; // dynamic resolution (dependent on datarate)
(uint8_t)capt -= halfDataRate; // always subtract datarate/2
if ((uint8_t)capt > halfDataRate) { // when longer than that, try to subtract once more
y++;
(uint8_t)capt -= halfDataRate;
}
if ((capt<<1) > halfDataRate) { // check overflow of counter and range
// this check is also dynamic, depends on current datarate
// the faster datarate the more precise must the signal be
if(last_valid == 0) {
last_bit = ((~edge)>>ICES1)&1; // rtf feature
store_bit(last_bit, 0); // rtf feature
store_bit ( 0, 1); // store bad bit
last_valid = 1;
}
last_bit = 0;
} else {
if (y) {
last_bit = ((~edge)>>ICES1)&1;
store_bit(last_bit, 0);
last_valid = 0;
bit_pos = 0;
} else {
if (bit_pos++) {
store_bit(last_bit, 0);
bit_pos = 0;
last_valid = 0;
}
}
}
}
// ==================================================================
void biphase_capture(void)
{
uint8_t y;
uint16_t capt;
uint16_t icr = ICR1;
TCCR1B ^= (1<255) store_pulse(255); else store_pulse((uint8_t)capt);
}
y = 0;
capt += halfDataRate >> 2; // dynamic resolution (dependent on datarate)
capt -= halfDataRate; // always subtract datarate/2
if (capt > halfDataRate) { // when longer than that, try to subtract once more
y++;
capt -= halfDataRate;
}
if ((capt<<1) > halfDataRate) { // check overflow of counter and range
// this check is also dynamic, depends on current datarate
// the faster datarate the more precise must the signal be
if (last_valid == 0) {
store_bit(bit_pos^1, 0); // rtf feature
store_bit ( 0, 1); // store bad bit
last_valid = 1;
}
bit_pos = 0;
} else {
if (y) {
store_bit(1, 0);
bit_pos = 0;
last_valid = 0;
} else {
if (bit_pos++) {
store_bit(0, 0);
bit_pos = 0;
last_valid = 0;
}
}
}
}
// ==================================================================
void miller_capture(void)
{
uint8_t y;
uint16_t capt;
uint16_t icr = ICR1;
TCCR1B ^= (1<255) store_pulse(255); else store_pulse((uint8_t)capt);
}
y = 0; //first operation must be 16 bits wide (counter can be up to 256 !)
capt -= halfDataRate << 1; // always subtract datarate
// from now on, 8bit operations are enough
capt += halfDataRate >> 2; // dynamic resolution (dependent on datarate)
if ((uint8_t)capt > halfDataRate) { // when longer than that, try to subtract once more
y++;
(uint8_t)capt -= halfDataRate;
}
if ((uint8_t)capt > halfDataRate) { // when longer than that, try to subtract once more
y++;
(uint8_t)capt -= halfDataRate;
}
if ((capt<<1) > halfDataRate) { // check overflow of counter and range
// this check is also dynamic, depends on current datarate
// the faster datarate the more precise must the signal be
last_bit = 0;
store_bit ( 0, 1); // store bad bit
} else {
if (y==2) { // only combination "101"
store_bit(0, 0);
store_bit(1, 0);
last_bit = 1;
} else if (!y) { // the same bit as previously
store_bit(last_bit, 0);
} else if (last_bit) { // y==1, last_bit=1
store_bit(0, 0);
last_bit = 0;
} else { // y==1, last_bit=0
store_bit(0, 0);
store_bit(1, 0);
last_bit = 1;
}
}
}
// ==================================================================
// Down Link setup function
// Requires: maxCaptureTimeLow and maxCaptureTimeHi
// (located here instead of level2 because of register variables)
void Capture(uint8_t style) {
ClearCaptureBuffers();
last_valid = 0;
TCCR1B = 0; //disable Counter1
captured_bit_count = 0;
capture_cnt = 0;
bit_pos = 0;
TCNT1 = ~maxCaptureTimeLow; //set timer with initial time
currentMaxTimeHi = ~maxCaptureTimeHi;
TIFR = TIFR | (1<>ICES1)&1;
store_bit(last_bit, 0);
break;
case 2 :
store_bit(bit_pos ^ 1, 0);
break;
default :
break;
}
}
if (capture_cnt != CAPTURE_SIZE) //flush captured bits
while (captured_bit_count != 0) {
store_bit(0,1);
}
enable_capture = 0;
TCCR1B = counter1set; //counter T1 running
sbi (TIMSK, TICIE1); //enable dummy capture
}
// ==================================================================
// Wait
void Wait(uint16_t period) {
TCCR1B = 0; //disable Counter1
TCNT1 = ~period; //set timer with initial time
currentMaxTimeHi = 0xFF;
TIFR = TIFR | (1<