diff options
| -rw-r--r-- | src/jtag/core.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/src/jtag/core.c b/src/jtag/core.c index 3021a103..e23cbaa2 100644 --- a/src/jtag/core.c +++ b/src/jtag/core.c @@ -975,10 +975,12 @@ int jtag_examine_chain(void) return ERROR_JTAG_INIT_FAILED; } - for (unsigned bit_count = 0; bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31;) + for (unsigned bit_count = 0; + tap && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31; + tap = jtag_tap_next_enabled(tap)) { uint32_t idcode = buf_get_u32(idcode_buffer, bit_count, 32); - tap->hasidcode = true; + if ((idcode & 1) == 0) { /* LSB must not be 0, this indicates a device in bypass */ @@ -990,7 +992,9 @@ int jtag_examine_chain(void) } else { - /* + tap->hasidcode = true; + + /* * End of chain (invalid manufacturer ID) some devices, such * as AVR will output all 1's instead of TDI input value at * end of chain. @@ -1015,10 +1019,8 @@ int jtag_examine_chain(void) tap->idcode = idcode; // ensure the TAP ID does matches what was expected - if (!jtag_examine_chain_match_tap(tap)) + if (!jtag_examine_chain_match_tap(tap)) return ERROR_JTAG_INIT_FAILED; - - tap = jtag_tap_next_enabled(tap); } /* see if number of discovered devices matches configuration */ |