Latest GPIO module on old RPi
Robin Hounsome (1539) 25 posts |
I’m trying to use an old RPi B dated ©2011 with a 26 pin GPIO header with RISCOS 5.24 and have hit a problem. It seems that the old RPi is not compatible with later versions of RISCOS 5.23/4 (sometime after 20-Dec-15) and GPIO 1.00 I’ve made tests as follows: RISCOS 5.23 13-Apr-17 and GPIO 1.00 GPIO Module is dormant, trying to enable the module reports Hardware not supported RISCOS 5.23 13-Apr-17 and GPIO 0.60 25-Feb-15 *gpiomachine reports We are running on Machine not detected! RISCOS 5.23 20-Dec-15 and GPIO 0.60 25-Feb-15 *gpiomachine reports We are running on RaspberryPi Mk2 B Rev1 So question. Is this a bug or has support for early RPis been dropped in the latest versions of RISCOS / GPIO? I can always roll back to an earlier version of RISCOS / GPIO if that’s whats needed. |
Rick Murray (539) 13406 posts |
Earlier versions of RISC OS used to have a way of detecting the board in use (as described here) but at some point this was removed (probably part of the somewhat flawed “you don’t need to know what the device is” logic). So that may explain why GPIO 0.60 behaves differently on the older and newer versions of RISC OS 5.23. As for GPIO 1.00, I can only assume it’s a bug. I don’t see any specific reason to drop support for the original Pi. |
Chris Hall (132) 3504 posts |
So question. Is this a bug or has support for early RPis been dropped in the latest versions of RISCOS / GPIO? What does !ScreenHelp report as your machine type please? AFAIK GPIO uses the RPi’s revision code to determine hardware GPIO pin assignments (using each known specific code rather then the bits in the later bit-map type revision field) and the module will remain dormant if it does not recognise the revision code. For example: !ScreenHelp will identify the hardware revision code. |
Robin Hounsome (1539) 25 posts |
For 5.24 and 5.23 13-Apr-17 Raspberry Pi model 1 B (256Mbytes) PCB revision 1 (02)[over-volted] For 5.23 20-Dec-15 Raspberry Pi (with firmware/ROM older than April 2016) For all 3 tests the Firmware date was 18-Feb-17 |
Chris Hall (132) 3504 posts |
I have a revision 02 Pi somewhere, I’ll see what I can do to help. Don’t hold your breath though! |
Robin Hounsome (1539) 25 posts |
Thanks Chris, don’t waste time on this. I guess my problem is a low priority edge case and I can simply roll back to using older versions of RISCOS and GPIO |