URL: <https://savannah.nongnu.org/bugs/?60008>
Summary: linuxspi programmer does not seem to release AVR reset when finished Project: AVR Downloader/UploaDEr Submitted by: None Submitted on: Thu 04 Feb 2021 10:27:28 PM UTC Category: None Severity: 3 - Normal Priority: 5 - Normal Item Group: None Status: None Privacy: Public Assigned to: None Originator Name: Ralf Herrmann Originator Email: ralf.herrm...@ilmsens.com Open/Closed: Open Release: SVN snapshot Discussion Lock: Any Programmer hardware: ARMv7 embededed computer Device type: ATmega328pb _______________________________________________________ Details: Dear avrdude team, first of all thanks for your nice work! I'm currently working on an embedded platform based on an ARMv7 embedded CPU and Linux (Debian Buster). The board has an AVR ATmega328pb attached to the A7 via SPI (AVR is slave) and the A7 also has one of its GPIOs connected to nRST of the AVR. Yesterday I fetched r1450 from svn, build it, and tested communication with the AVR. I'm using programmer linuxspi (obviously) and specify reset pin via command line as per man page. At first it went fine and avrdude let me upload my app to flash. Verification was successful. However, after uploading the app, the AVR did not respond any more to SPI commands i sent from the A7. Long story short, i ended up checking the source code in linuxspi.c and did not see any code that releases the reset GPIO line of the AVR. To test my suspicion i copied a few lines from linuxspi_open() to linuxspi_close() and changed it so that nRST is released. That did the trick for me, after upload to flash AVR immediately reacts to SPI connection from A7. I'm not 100% sure this is unintended behaviour, however, i found a way older version of avrdude that has the initial code for linuxspi programmer (i think based on 6.1). This older code used the (now deprecated) sysfs-way to operate the reset pin. It has indeed code to release the reset pin through linuxspi_close() (it actually makes the GPIO an input to the host CPU again thereby letting the pullup resistor do the actual release). I hope you fond this report useful. If you need more detail, let me know. Keep up the good work! BR, Ralf _______________________________________________________ Reply to this item at: <https://savannah.nongnu.org/bugs/?60008> _______________________________________________ Message sent via Savannah https://savannah.nongnu.org/