diff options
Diffstat (limited to 'src/jtag/bitbang.c')
| -rw-r--r-- | src/jtag/bitbang.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/src/jtag/bitbang.c b/src/jtag/bitbang.c index 82e92a21..198a741f 100644 --- a/src/jtag/bitbang.c +++ b/src/jtag/bitbang.c @@ -132,21 +132,35 @@ void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size) enum tap_state saved_end_state = end_state; int bit_cnt; - if (ir_scan) - bitbang_end_state(TAP_SI); - else - bitbang_end_state(TAP_SD); + if (!((!ir_scan && (cur_state == TAP_SD)) || (ir_scan && (cur_state == TAP_SI)))) + { + if (ir_scan) + bitbang_end_state(TAP_SI); + else + bitbang_end_state(TAP_SD); - bitbang_state_move(); - bitbang_end_state(saved_end_state); + bitbang_state_move(); + bitbang_end_state(saved_end_state); + } for (bit_cnt = 0; bit_cnt < scan_size; bit_cnt++) { + /* set TMS high on the last bit unless we want to end in TAP_SD/SI */ + int tms; + if ((ir_scan && (end_state == TAP_SI)) || + (!ir_scan && (end_state == TAP_SD))) + { + tms = 0; + } else { + tms = (bit_cnt==scan_size-1) ? 1 : 0; + } + /* if we're just reading the scan, but don't care about the output * default to outputting 'low', this also makes valgrind traces more readable, * as it removes the dependency on an uninitialised value */ - if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1)) { + if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1)) + { bitbang_interface->write(0, (bit_cnt==scan_size-1) ? 1 : 0, 1); bitbang_interface->write(1, (bit_cnt==scan_size-1) ? 1 : 0, 1); } else { |