I've recently acquired a Raspberry Pi 4/4GB, which I'm planning to use in place of a failed motherboard/GPU in an old 24" iMac, re-using only the display, PSU, fans and speakers.
Initially, I'm at the point of trying to get the board to boot to a usable state with Raspbian Desktop, connected to the official Raspberry Pi USB C PSU, an external HDMI display and a USB keyboard and mouse.
After downloading and installing the February 2020 (release date 2020-02-13) "Raspbian Buster with desktop and recommended software" to a 32GB SanDisk SD card, I can get the board to boot, but appears to be totally frozen after getting to display the graphical desktop - the mouse cursor does not move, neither does it respond to keyboard input.
I'm aware there at least have been issues with the 4GB variant of this board with some versions of Linux, in terms of not enabling USB, but I've not managed to ascertain whether this should now be fixed. The Raspbian Release notes suggest the distro does support the Raspberry Pi 4, but makes no mention of specific fixes, other than a change to ensure the SPI EEPROM is updated to the latest version.
What I've tried so far:
/boot/config.txtfrom my Mac and making the following changes, before transferring to the card to the Raspberry Pi:
- Trying 3 different USB keyboards and mouse, including one known to work with other Raspberry Pi boards.
- One optical mouse I've tried which uses visible red light flashes briefly when plugged in (drawing too much power?).
- Trying the keyboard and mouse in both the USB and USB 3 ports.
Unfortunately the board will only boot once like this - I have to reflash the whole SD card before it will boot again, probably because I'm not able to properly shut down the system before powering off.
My questions are therefore:
- how can I avoid having to reflash the SD each time? This is really slowing down troubleshooting!
- is there any way to test whether the system is running or has frozen without working USB?
- would changes written to
/boot/config.txton a Mac prior to boot take effect? If not, what would be the correct approach, given I cannot currently interact with the system?
- is there another way to interact with the booted system other than USB? For example, does the default install enable
- is my Raspberry Pi 4 potentially faulty? The RP4 has been out a while now, and it seems reasonable to expect it to work out-of-the-box with Raspbian.