Got it working. It wasn’t an electrical problem but a software one. I used the software from another built that was running the PIC with a 20 MHz crystal while I intended to run the board at 16 MHz. Therefore I had to adjust some settings in order get the oscillator set up correctly. Additionally some header were still missing. Below the nearly complete board. One header is still unpopulated.Ok…Now focussing on the software…
After I received the PCB (PIC LCD Backpack) from Dangerous Prototypes it was lying around for some time because I wanted to finish some other projects first. I used that time for sourcing the required parts. Finally I started working on this and populating the PCB was quite quick. The result is not that bad. First checks showed that the power supply is doing fine and the first program upload (using a PICkit 3) was also successful.
When connecting it to the USB to a computer it turns out that the USB communication is not ok. The computer is recognizing that something is connected to the USB bus but is not able to identify the device (VID and PID zeroed). Well something is wrong here. I suppose an electrical problem. The PIC itself seems to be fine. At least I could debug it from the IDE.
Ok. Need to check if there’s any cold soldering joint…To be continued…
Version 12.09 of OpenWRT is running really well on my TL-WA801ND access points and in the meantime the OpenWRT project is working on the upcoming version named “Barrier Breaker”. I ported this version to the TL-WA801ND v2 as well and it is also running fine.
If anyone is interested in this I uploaded the required patches here and a precompiled firmware binary here. The precompiled binary provides the same feature set as the one for version 12.09 does. In case that you wish to compile it your own you need to retrieve commit c3e1e1cb2f09ebc8c35455f2ff77061f937dfb05 (r37917) from the OpenWRT git repository in order to get the patch applied without error. I.e. issue
git reset --hard c3e1e1cb2f09ebc8c35455f2ff77061f937dfb05 after cloning the repository.