[bug #52886] Incorrectly hardcoded fuse addresses in STK500v2 ISP mode

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[bug #52886] Incorrectly hardcoded fuse addresses in STK500v2 ISP mode

Joerg Wunsch-6
URL:
  <http://savannah.nongnu.org/bugs/?52886>

                 Summary: Incorrectly hardcoded fuse addresses in STK500v2 ISP
mode
                 Project: AVR Downloader/UploaDEr
            Submitted by: None
            Submitted on: Sun 14 Jan 2018 03:41:54 PM UTC
                Category: None
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: None
                  Status: None
                 Privacy: Public
             Assigned to: None
         Originator Name: Joao Rosa
        Originator Email: [hidden email]
             Open/Closed: Open
                 Release: SVN snapshot
         Discussion Lock: Any
     Programmer hardware:
             Device type:

    _______________________________________________________

Details:

On file "stk500v2.c", functions stk500isp_write_byte() and
stk500isp_read_byte() incorrectly hardcode the address of "fuse"/"lfuse",
"hfuse" and "efuse".

This is only needed for HVSP and PP modes, not ISP (probably copy/paste
error?). Though this is a "silent" bug that currently doesn't have any effect,
it may conceivably manifest itself in the future if future chips access the
fuses using some kind of addressing scheme, that is, using a0, a1, a2, etc. in
the avrdude.conf definitions.

In fact I found this bug because I'm writing a programmer for UPDI chips and
want to use the STK500v2 interface.

I'll copy a few lines of code from "stk500v2.c" as example:

1942  } else if (strcmp(mem->desc, "hfuse") == 0) {
1943    buf[0] = CMD_READ_FUSE_ISP;
1944    addr = 1;   /* This line is not needed/bug */

I believe lines like this one can be safely deleted.




    _______________________________________________________

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  <http://savannah.nongnu.org/bugs/?52886>

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