Skip to content

Commit

Permalink
add em4100 protocol decoder
Browse files Browse the repository at this point in the history
  • Loading branch information
@merlokk
merlokk committed Jul 24, 2024
1 parent a7d08eb commit 32f6ab8
Showing 1 changed file with 119 additions and 14 deletions.
133 changes: 119 additions & 14 deletions firmware/application/src/rfid/reader/lf/protocols/protocol_em4100.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@
#include <stdlib.h>
#include <string.h>
#include <utils/manchester_decoder.h>
#include <utils/bit_buffer.h>
#include "lfrfid_protocols.h"

typedef uint64_t EM4100DecodedData;
Expand All @@ -25,13 +26,16 @@ typedef uint64_t EM4100DecodedData;
#define EM4100_DECODED_DATA_SIZE (5)
#define EM4100_ENCODED_DATA_SIZE (sizeof(EM4100DecodedData))

#define EM_READ_SHORT_TIME_BASE (256)
#define EM_READ_LONG_TIME_BASE (512)
#define EM_READ_JITTER_TIME_BASE (100)
#define EM4100_RAW_DATA_SIZE (50)

#define EM_READ_TIME1_BASE (0x40)
#define EM_READ_TIME2_BASE (0x60)
#define EM_READ_TIME3_BASE (0x80)
#define EM_READ_JITTER_TIME_BASE (0x10)

typedef struct {
uint8_t data[EM4100_DECODED_DATA_SIZE];

uint8_t data[EM4100_DECODED_DATA_SIZE];
EM4100DecodedData encoded_data;
uint8_t encoded_data_index;
bool encoded_polarity;
Expand Down Expand Up @@ -66,26 +70,54 @@ uint32_t protocol_em4100_get_t5577_bitrate(ProtocolEM4100* proto) {
}
}

uint16_t protocol_em4100_get_short_time_low(ProtocolEM4100* proto) {
return EM_READ_SHORT_TIME_BASE / protocol_em4100_get_time_divisor(proto) -
uint8_t protocol_em4100_get_time1_low(ProtocolEM4100* proto) {
return EM_READ_TIME1_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

uint8_t protocol_em4100_get_time1_high(ProtocolEM4100* proto) {
return EM_READ_TIME1_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

bool protocol_em4100_get_time1(ProtocolEM4100* proto, uint8_t interval) {
return
interval >= protocol_em4100_get_time1_low(proto) &&
interval <= protocol_em4100_get_time1_high(proto);
}

uint8_t protocol_em4100_get_time2_low(ProtocolEM4100* proto) {
return EM_READ_TIME2_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

uint16_t protocol_em4100_get_short_time_high(ProtocolEM4100* proto) {
return EM_READ_SHORT_TIME_BASE / protocol_em4100_get_time_divisor(proto) +
uint8_t protocol_em4100_get_time2_high(ProtocolEM4100* proto) {
return EM_READ_TIME2_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

uint16_t protocol_em4100_get_long_time_low(ProtocolEM4100* proto) {
return EM_READ_LONG_TIME_BASE / protocol_em4100_get_time_divisor(proto) -
bool protocol_em4100_get_time2(ProtocolEM4100* proto, uint8_t interval) {
return
interval >= protocol_em4100_get_time2_low(proto) &&
interval <= protocol_em4100_get_time2_high(proto);
}

uint8_t protocol_em4100_get_time3_low(ProtocolEM4100* proto) {
return EM_READ_TIME3_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

uint16_t protocol_em4100_get_long_time_high(ProtocolEM4100* proto) {
return EM_READ_LONG_TIME_BASE / protocol_em4100_get_time_divisor(proto) +
uint8_t protocol_em4100_get_time3_high(ProtocolEM4100* proto) {
return EM_READ_TIME3_BASE / protocol_em4100_get_time_divisor(proto) -
EM_READ_JITTER_TIME_BASE / protocol_em4100_get_time_divisor(proto);
}

bool protocol_em4100_get_time3(ProtocolEM4100* proto, uint8_t interval) {
return
interval >= protocol_em4100_get_time3_low(proto) &&
interval <= protocol_em4100_get_time3_high(proto);
}

ProtocolEM4100* protocol_em4100_alloc(void) {
ProtocolEM4100* proto = malloc(sizeof(ProtocolEM4100));
proto->clock_per_bit = 64;
Expand Down Expand Up @@ -240,11 +272,84 @@ bool protocol_em4100_decoder_feed(ProtocolEM4100* proto, bool level, uint32_t du
return result;
};

void protocol_em4100_decoder_decode(ProtocolEM4100* proto, uint8_t* data, size_t datalen) {
protocol_em4100_decoder_start(proto);
uint8_t read_bit_interval(ProtocolEM4100* proto, uint8_t interval) {
if (protocol_em4100_get_time1(proto, interval))
return 1;

if (protocol_em4100_get_time2(proto, interval))
return 2;

if (protocol_em4100_get_time3(proto, interval))
return 3;

return 0;
}


uint8_t decode(ProtocolEM4100* proto, uint8_t* data, size_t datalen) {
BitBuffer* bit_buffer = bit_buffer_alloc(EM4100_RAW_DATA_SIZE);

uint8_t sync = 1; //After the current interval process is processed, is it on the judgment line
uint8_t cardindex = 0; //Record change number
for (int i = 0; i < datalen; i++) {
uint8_t bit_interval = read_bit_interval(proto, data[i]);
switch (sync) {
case 1: //Synchronous state
switch (bit_interval) {
case 0: //TheSynchronousState1T,Add1Digit0,StillSynchronize
bit_buffer_append_bit(bit_buffer, 0);
cardindex++;
break;
case 1: // Synchronous status 1.5T, add 1 digit 1, switch to non -synchronized state
bit_buffer_append_bit(bit_buffer, 1);
cardindex++;
sync = 0;
break;
case 2: //Synchronous2T,Add2Digits10,StillSynchronize
bit_buffer_append_bit(bit_buffer, 1);
cardindex++;
bit_buffer_append_bit(bit_buffer, 0);
cardindex++;
break;
default:
return 0;
}
break;
case 0: //Non -synchronous state
switch (bit_interval) {
case 0: //1TInNonSynchronousState,Add1Digit1,StillNonSynchronous
bit_buffer_append_bit(bit_buffer, 1);
cardindex++;
break;
case 1: // In non -synchronous status 1.5T, add 2 digits 10, switch to the synchronous state
bit_buffer_append_bit(bit_buffer, 1);
cardindex++;
bit_buffer_append_bit(bit_buffer, 0);
cardindex++;
sync = 1;
break;
case 2: //The2TOfTheNonSynchronousState,ItIsImpossibleToOccur,ReportAnError
return 0;
default:
return 0;
}
break;
}
if (cardindex >= EM4100_RAW_DATA_SIZE * 8)
break;
}

bit_buffer_dump(bit_buffer);

bit_buffer_free(bit_buffer);

return 1;
}

void protocol_em4100_decoder_decode(ProtocolEM4100* proto, uint8_t* data, size_t datalen) {
protocol_em4100_decoder_start(proto);

decode(proto, data, datalen);
}

static void em4100_write_nibble(bool low_nibble, uint8_t data, EM4100DecodedData* encoded_data) {
Expand Down

0 comments on commit 32f6ab8

Please sign in to comment.