From 47b78133a07719094a01d745c6beea0f0954b615 Mon Sep 17 00:00:00 2001 From: pwpiwi Date: Wed, 22 Nov 2017 17:46:00 +0100 Subject: [PATCH] minor iso14443a timing fixes to avoid select errors: * take setup frame guard time (SFGT) into account * adjust iso14a_timeout by FPGA delays * don't give up on first WUPA. Retry several times --- armsrc/iso14443a.c | 95 +++++++++++++++++++++++++++++++--------------- 1 file changed, 64 insertions(+), 31 deletions(-) diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c index 89ef23d4..a0fe2326 100644 --- a/armsrc/iso14443a.c +++ b/armsrc/iso14443a.c @@ -189,33 +189,15 @@ void iso14a_set_trigger(bool enable) { void iso14a_set_timeout(uint32_t timeout) { - iso14a_timeout = timeout; - if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106); + iso14a_timeout = timeout - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8); + if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", timeout, timeout / 106); } -static void iso14a_set_ATS_timeout(uint8_t *ats) { - - uint8_t tb1; - uint8_t fwi; - uint32_t fwt; - - if (ats[0] > 1) { // there is a format byte T0 - if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1) - if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1) - tb1 = ats[3]; - } else { - tb1 = ats[2]; - } - fwi = (tb1 & 0xf0) >> 4; // frame waiting indicator (FWI) - fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc - - iso14a_set_timeout(fwt/(8*16)); - } - } +uint32_t iso14a_get_timeout(void) { + return iso14a_timeout + (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/(16*8); } - //----------------------------------------------------------------------------- // Generate the parity value for a byte sequence // @@ -1277,7 +1259,7 @@ static void PrepareDelayedTransfer(uint16_t delay) // Transmit the command (to the tag) that was placed in ToSend[]. // Parameter timing: // if NULL: transfer at next possible time, taking into account -// request guard time and frame delay time +// request guard time, startup frame guard time and frame delay time // if == 0: transfer immediately and return time of transfer // if != 0: delay transfer until time specified //------------------------------------------------------------------------------------- @@ -1685,6 +1667,59 @@ int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) return Demod.len; } + +static void iso14a_set_ATS_times(uint8_t *ats) { + + uint8_t tb1; + uint8_t fwi, sfgi; + uint32_t fwt, sfgt; + + if (ats[0] > 1) { // there is a format byte T0 + if ((ats[1] & 0x20) == 0x20) { // there is an interface byte TB(1) + if ((ats[1] & 0x10) == 0x10) { // there is an interface byte TA(1) preceding TB(1) + tb1 = ats[3]; + } else { + tb1 = ats[2]; + } + fwi = (tb1 & 0xf0) >> 4; // frame waiting time integer (FWI) + if (fwi != 15) { + fwt = 256 * 16 * (1 << fwi); // frame waiting time (FWT) in 1/fc + iso14a_set_timeout(fwt/(8*16)); + } + sfgi = tb1 & 0x0f; // startup frame guard time integer (SFGI) + if (sfgi != 0 && sfgi != 15) { + sfgt = 256 * 16 * (1 << sfgi); // startup frame guard time (SFGT) in 1/fc + NextTransferTime = MAX(NextTransferTime, Demod.endTime + (sfgt - DELAY_AIR2ARM_AS_READER - DELAY_ARM2AIR_AS_READER)/16); + } + } + } +} + + +static int GetATQA(uint8_t *resp, uint8_t *resp_par) { + +#define WUPA_RETRY_TIMEOUT 10 // 10ms + uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP + + uint32_t save_iso14a_timeout = iso14a_get_timeout(); + iso14a_set_timeout(1236/(16*8)+1); // response to WUPA is expected at exactly 1236/fc. No need to wait longer. + + uint32_t start_time = GetTickCount(); + int len; + + // we may need several tries if we did send an unknown command or a wrong authentication before... + do { + // Broadcast for a card, WUPA (0x52) will force response from all cards in the field + ReaderTransmitBitsPar(wupa, 7, NULL, NULL); + // Receive the ATQA + len = ReaderReceive(resp, resp_par); + } while (len == 0 && GetTickCount() <= start_time + WUPA_RETRY_TIMEOUT); + + iso14a_set_timeout(save_iso14a_timeout); + return len; +} + + // performs iso14443a anticollision (optional) and card select procedure // fills the uid and cuid pointer unless NULL // fills the card info record unless NULL @@ -1692,7 +1727,6 @@ int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) // and num_cascades must be set (1: 4 Byte UID, 2: 7 Byte UID, 3: 10 Byte UID) // requests ATS unless no_rats is true int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades, bool no_rats) { - uint8_t wupa[] = { 0x52 }; // 0x26 - REQA 0x52 - WAKE-UP uint8_t sel_all[] = { 0x93,0x20 }; uint8_t sel_uid[] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00}; uint8_t rats[] = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0 @@ -1712,11 +1746,9 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u p_hi14a_card->ats_len = 0; } - // Broadcast for a card, WUPA (0x52) will force response from all cards in the field - ReaderTransmitBitsPar(wupa, 7, NULL, NULL); - - // Receive the ATQA - if(!ReaderReceive(resp, resp_par)) return 0; + if (!GetATQA(resp, resp_par)) { + return 0; + } if(p_hi14a_card) { memcpy(p_hi14a_card->atqa, resp, 2); @@ -1845,8 +1877,9 @@ int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, u // reset the PCB block number iso14_pcb_blocknum = 0; - // set default timeout based on ATS - iso14a_set_ATS_timeout(resp); + // set default timeout and delay next transfer based on ATS + iso14a_set_ATS_times(resp); + } return 1; } -- 2.39.2