Pi-top hub mk1 control with C language - help needed please

Hi,
I’ve been trying for days to get this to work properly to no avail. Does anyone have any C code to communicate with the hub mk1 to control the screen brightness and retrieve the battery status information? I’m more than capable of writing a couple of apps to sort this out but without the details I can’t proceed. The only information I can find refers to a rricharz github repo that as soon as you compile the brightness.c file and then run it, the pi-top then goes into a shutdown sequence. If I can boost the screen brightness so I can read the content and have a notification of low battery then I’ll be a happy chappy, plus I’m more than willing to post my github repo once it’s done.

Let’s breath some more life into these pi-tops please! Oh and my pi-top is a grey unit with the touchpad to the right hand side with a FHD screen…

Thanks, Dan R

Partially Working Modifications to a Pi-Top 1 FHD with an 8Gb Pi 4
In the mean time, to get this working in a useable state, I did the following mods to the mk1 PCB:

  1. cut the test pad P15 across the full diameter so it can be reverted at a later date.
  2. Soldered a 1K ohm resistor to the half of the P15 pad to the two plated through holes close to pins 7 of U200 (ATTiny24a uC), this pulls the PWM control of the backlight to full so you can actually see the display!
  3. Added a 22K ohm 0805 resistor across R307 to adjust the TPS54332 DC to DC converter, this means we now get 5.3V instead of 5.1V which powers the Pi4 properly and without voltage warnings (so far so good).
  4. I also added a 220uF 10V aluminium electrolytic across the 2 MLCC capacitors to the left of the inductor to improve transient response of the DC to DC converter.
  5. Using 32bit Raspberry Pi OS means I can update the OS and get the power off control and battery monitor working. Shame it doesn’t work on 64bit!

I used a USB to USB-C lead to power the Pi4 and just took the official Raspberry Pi Micro HDMI lead and carefully cut off the white plastic around the connectors. Now the leads fit and are coiled up nicely inside. Heatsinks added and I might add a fan if the temps get too high.

If anyone wants pics I’ll upload them as well, assuming I’m allowed to, so others can benefit from this huge upgrade. I love the case and screen but just wish there was more support so others can use it properly and not throw it in the bin and increase e-Waste which harms the planet!