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lf t55xx chk m - tweaking the algo

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This commit is contained in:
iceman1001
2020-08-21 17:46:29 +02:00
parent 4a09a1e17f
commit dc6e4ea4ea
1 changed files with 8 additions and 2 deletions
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10
armsrc/lfops.c
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@@ -2074,7 +2074,7 @@ void T55xx_ChkPwds(uint8_t flags) {
b1 = 0; b1 = 0;
T55xxReadBlock(0, 0, true, 0, 0, downlink_mode); T55xxReadBlock(0, 0, true, 0, 0, downlink_mode);
for (uint16_t j = 0; j < CHK_SAMPLES_SIGNAL; ++j) { for (uint16_t j = 0; j < CHK_SAMPLES_SIGNAL; ++j) {
b1 += buf[j]; b1 += (buf[j] * buf[j]);
} }
b1 *= b1; b1 *= b1;
b1 >>= 8; b1 >>= 8;
@@ -2082,6 +2082,9 @@ void T55xx_ChkPwds(uint8_t flags) {
} }
baseline_faulty >>= 5; baseline_faulty >>= 5;
if (DBGLEVEL >= DBG_DEBUG)
Dbprintf("Baseline " _YELLOW_("%llu"), baseline_faulty);
uint8_t *pwds = BigBuf_get_EM_addr(); uint8_t *pwds = BigBuf_get_EM_addr();
uint16_t pwd_count = 0; uint16_t pwd_count = 0;
@@ -2133,7 +2136,7 @@ void T55xx_ChkPwds(uint8_t flags) {
uint64_t sum = 0; uint64_t sum = 0;
for (uint16_t j = 0; j < CHK_SAMPLES_SIGNAL; ++j) { for (uint16_t j = 0; j < CHK_SAMPLES_SIGNAL; ++j) {
sum += buf[j]; sum += (buf[j] * buf[j]);
} }
sum *= sum; sum *= sum;
sum >>= 8; sum >>= 8;
@@ -2141,6 +2144,9 @@ void T55xx_ChkPwds(uint8_t flags) {
int64_t tmp_dist = (baseline_faulty - sum); int64_t tmp_dist = (baseline_faulty - sum);
curr = ABS(tmp_dist); curr = ABS(tmp_dist);
if (DBGLEVEL >= DBG_DEBUG)
Dbprintf("%08x has distance " _YELLOW_("%llu"), pwd, curr);
if (curr > prev) { if (curr > prev) {
idx = i; idx = i;
prev = curr; prev = curr;