bug #42267: jtag3isp fails to read lock and fuse bytes directly

after changing lock byte
* stk500v2.c (stk500isp_write_byte): As a workaround for broken
tool firmware, add 10 ms of delay before returning from any
single-byte write operation.



git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@1337 81a1dc3b-b13d-400b-aceb-764788c761c2
This commit is contained in:
joerg_wunsch 2014-10-07 15:21:14 +00:00
parent 71e437432f
commit 4822833ce4
3 changed files with 20 additions and 13 deletions

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@ -1,3 +1,11 @@
2014-10-07 Joerg Wunsch <j.gnu@uriah.heep.sax.de>
bug #42267: jtag3isp fails to read lock and fuse bytes directly
after changing lock byte
* stk500v2.c (stk500isp_write_byte): As a workaround for broken
tool firmware, add 10 ms of delay before returning from any
single-byte write operation.
2014-10-06 Joerg Wunsch <j.gnu@uriah.heep.sax.de>
* stk500v2.c: Use stk500isp_read_byte/stk500isp_write_byte for

2
NEWS
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@ -22,6 +22,8 @@ Current:
* Bugfixes
- bug #22248: Read efuse error (partial fix)
- bug #42267: jtag3isp fails to read lock and fuse bytes directly
after changing lock byte
* Internals:
- ...

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@ -2241,19 +2241,16 @@ static int stk500isp_write_byte(PROGRAMMER * pgm, AVRPART * p, AVRMEM * mem,
return -1;
}
if (buf[0] == CMD_PROGRAM_FUSE_ISP) {
/*
* The JTAGICE3 needs one leave progmode / enter progmode cycle
* after writing fuses, before being able to read them back.
*/
buf[0] = CMD_LEAVE_PROGMODE_ISP;
buf[1] = 1; // preDelay;
buf[2] = 1; // postDelay;
stk500v2_command(pgm, buf, 3, sizeof(buf));
pgm->program_enable(pgm, p);
}
/*
* Prevent verification readback to be too fast, see
* https://savannah.nongnu.org/bugs/index.php?42267
*
* After all, this is just an ugly hack working around some
* brokeness in the Atmel firmware starting with the AVRISPmkII (the
* old JTAGICEmkII isn't affected). Let's hope 10 ms of additional
* delay are good enough for everyone.
*/
usleep(10000);
return 0;
}