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Merge pull request #828 from tharexde/check_em4x50

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speed up "lf search" process (EM4x50)
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Iceman 2020-07-01 10:21:11 +02:00 • committed by GitHub
commit 9d727bca7d
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1 changed files with 42 additions and 4 deletions
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46
armsrc/em4x50.c
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@ -74,6 +74,7 @@ static em4x50_tag_t tag = {
#define EM4X50_T_TAG_FULL_PERIOD 64
#define EM4X50_T_TAG_TPP 64
#define EM4X50_T_TAG_TWA 64
#define EM4X50_T_WAITING_FOR_SNGLLIW 50
#define EM4X50_T_WAITING_FOR_DBLLIW 1550
#define EM4X50_TAG_TOLERANCE 8
@ -420,6 +421,34 @@ static void em4x50_send_word(const uint8_t bytes[4]) {
em4x50_send_bit(0);
}
static bool find_single_listen_window(void) {
// find single listen window
int cnt_pulses = 0;
while (cnt_pulses < EM4X50_T_WAITING_FOR_SNGLLIW) {
// identification of listen window is done via evaluation of
// pulse lengths
if (check_pulse_length(get_pulse_length(), 3 * EM4X50_T_TAG_FULL_PERIOD)) {
if (check_pulse_length(get_pulse_length(), 2 * EM4X50_T_TAG_FULL_PERIOD)) {
// listen window found
return true;
}
} else {
cnt_pulses++;
}
}
return false;
}
static bool find_double_listen_window(bool bcommand) {
// find two successive listen windows that indicate the beginning of
@ -482,6 +511,15 @@ static bool find_double_listen_window(bool bcommand) {
return false;
}
static bool find_em4x50_tag(void) {
// function is used to check wether a tag on the proxmark is an
// EM4x50 tag or not -> speed up "lf search" process
return (find_single_listen_window());
}
static bool request_receive_mode(void) {
// To issue a command we have to find a listen window first.
@ -764,7 +802,7 @@ void em4x50_info(em4x50_data_t *etd) {
em4x50_setup_read();
// set gHigh and gLow
if (get_signalproperties()) {
if (get_signalproperties() && find_em4x50_tag()) {
if (etd->pwd_given) {
@ -803,7 +841,7 @@ void em4x50_read(em4x50_data_t *etd) {
em4x50_setup_read();
// set gHigh and gLow
if (get_signalproperties()) {
if (get_signalproperties() && find_em4x50_tag()) {
if (etd->addr_given) {
@ -924,7 +962,7 @@ void em4x50_write(em4x50_data_t *etd) {
em4x50_setup_read();
// set gHigh and gLow
if (get_signalproperties()) {
if (get_signalproperties() && find_em4x50_tag()) {
// reorder word according to datasheet
msb2lsb_word(etd->word);
@ -979,7 +1017,7 @@ void em4x50_write_password(em4x50_data_t *etd) {
em4x50_setup_read();
// set gHigh and gLow
if (get_signalproperties()) {
if (get_signalproperties() && find_em4x50_tag()) {
// login and change password
if (login(etd->password)) {