a few details about this site
2013 February 06 11:46
After a few recent breakthroughs, I’m now able to connect to the CMSIS-DAP firmware on my Freescale Freedom board and successfully read and write core registers and memory – using muFORTH!
Two days ago, after modifying the OSX USB support in muFORTH (to support USB HIDs), I was able to turn the “connect” LED on the board on and off. This meant that the connection between muFORTH and the HID firmware was working.
Then, yesterday afternoon I successfully read the IDCODE from the on-chip SW-DP. This required getting the connection sequence right – sending a binary string to the SW-DP. ARM’s documentation – the ARM Debug Interface v5 spec and the ADI v5.1 supplement – disagreed on what this sequence should be. I settled on sending 56 ones followed by 8 zeros, and this seemed to work.
My next hurdle was to try to read the chip’s memory. But any access to AP (access port) registers failed, returning a FAULT. It turns out that it is necessary to first turn on the CSYSPWRUPREQ and CSYSDBGREQ bits in the DP.CTRLSTAT register... Once I did this, the chip was mine!
Very cool.
2013 January 23 13:01
A new start?
I’m putting this crufty old site online again, but in an entirely new way: it’s now statically generated – using Lua! – and then pushed to GitHub, to be served by their (free!) GitHub Pages service.
I’m not sure how much time I’m going to spend in the near future grooming this site, since my next project is to tackle some form of blog for muFORTH, but I’m happy to have it online again.
See earlier journal entries at