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Soekris net4501 GPIO on FreeBSD 7.0

I finally picked up some small parts (leds, breadboard, leads, multimeter) from Fry's to start work on my universal remote project. Yes, I know you can buy universal remotes. I want to learn more electronics, so why not use this as a starter project?

Since my Soekris box is now free of it's router duties, I can use it for this project. To do this, I'll need two pieces: an infrared receiver, and an infrared emitter. I bought an infrared emitter led today, and I just need to buy a receiver online (they're like $2).

Before getting there, I needed to learn how to drive the GPIO ports on the net4501.

It was pretty simple to do, nd after hooking up a few wires I had an LED that blinked after a few hours of reading and hacking. The code itself was trivial to write, I just had to learn how to talk to the GPIO ports.

After writing the blinking code, I decided the next step was clearly to add fading to the LED. This is commonly done with PWM (pulse-width modulation). Apple made this technique famous with its "breathing" LED lights on the monitors and laptops when the devices were in sleep mode.

At any rate, I have successfully written code that makes both the error led and the PIO5 (GPIO 0) pin "breathe".

Download glow.c

Soekris net4501 upgrade to FreeBSD 7.0

I've definitely spent 10+ hours in the past 2 days trying to get this system upgraded from 6.0 to 7.0...

Why? First, I was using the wrong power supply, so it would randomly reboot during startup (4 hours, after before I figured that one out, after compiling zillions of kernels, even trying GENERIC from 6.2, 6.3, and 7.0). Then, I couldn't get a stable system image that would boot successfully. It would halt trying to run /sbin/init. Not sure why.

I was initially making my own image with mdconfig, and rsyncing the entire system into a file-backed fs. Then I dd'd this image to my compactflash and put it in the net4501. I gave up on that after several hours, and did this instead:

  1. Bring up a new vmware instance with 2 disks. 1 800mb disk and 1 5gb disk.
  2. Install 7.0-RC1, only install kernel and base.
  3. Mount the 5gb disk (newfs /dev/sd1, mount /dev/sd1 /usr/src) and unpack the kernel sources there. Build kernel (For the soekris box).
  4. Make any necessary config changes (serial console, etc)
  5. Shutdown machine
  6. Use qemu-img to convert the vmware disk into a raw disk image
  7. dd the new image to compact flash.
  8. Rejoice. I have a working net4501 now.
In testing in qemu, I get random timeouts talking to ad0. On the soekris board, I get random timeouts to ad0. wtf :(

Boot into safe-mode, and everything seems find. (Safe mode turns off DMA, iirc)