[avrdude-dev] [bug #43912] PATCH avrdude direct SPI mode NULL pointer crash

[David Fries]

URL:
  <http://savannah.nongnu.org/bugs/?43912>

                 Summary: PATCH avrdude direct SPI mode NULL pointer crash
                 Project: AVR Downloader/UploaDEr
            Submitted by: dfries
            Submitted on: Fri 02 Jan 2015 02:34:56 AM GMT
                Category: None
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: None
                  Status: None
                 Privacy: Public
             Assigned to: None
         Originator Name: David Fries
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any

    _______________________________________________________

Details:

The AVR serial programmer protocol is SPI, so it would be nice to use avrdude
to send and receive data over SPI for debugging while the microcontroller is
up and running, seems someone else agreed and implemented a direct SPI
terminal mode, however use USBtiny and avrdude crashes when giving spi to
enter direct SPI mode.  The man page lists "Only supported on parallel bitbang
programmers.", however the requirement really is to be able to be able to set
RESET high (or float), and the circuit must allow SS (slave select) to be
pulled low, but unlike RESET can be left low the entire time, making it easy
enough to get around in the circuit.

I'm including a patch for both 5.x and 6 avrdude to fix the crash for any
programmer that doesn't support setpin, and implementing support for USBtiny,
the limitation is SS held low and transferring multiples of 4 bytes at a
time.

I would prefer to use a "spi_send", "spi_bytes" or some command different from
the "send" because it would be really easy to accidentally be in programming
mode without the normal checks.



    _______________________________________________________

File Attachments:


-------------------------------------------------------
Date: Fri 02 Jan 2015 02:34:56 AM GMT  Name: spi_fix_5.11.1.patch  Size: 4kB  
By: dfries
fix for version 5 and 6
<http://savannah.nongnu.org/bugs/download.php?file_id=32744>
-------------------------------------------------------
Date: Fri 02 Jan 2015 02:34:56 AM GMT  Name: spi_fix_6.patch  Size: 6kB   By:
dfries
fix for version 5 and 6
<http://savannah.nongnu.org/bugs/download.php?file_id=32745>

    _______________________________________________________

Reply to this item at:

  <http://savannah.nongnu.org/bugs/?43912>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.nongnu.org/