SAMx4 1.0
Posted: Fri Dec 22, 2023 11:40 am
So thanks to lots of testing by Pedro Peña across his CoCo collection, SAMx4 now supports 4K and 16K ram sizes (and the extra 16K ram size in the '785).
https://www.6809.org.uk/dragon/samx4/
Pedro's also designed a smaller version of the board, which is in the "rockyhill" branch in the gitlab repository.
He did come across a slight problem in his CoCo 2 during testing which I've noticed also affects my PAL machine: the SAM sits under the keyboard, really close, and the keyboard has a metal backing plate! Means the JTAG pins kinda need to be bent over to clear it, and even some shielding may be required... Maybe I need to get me one of those pogo pin programming cables...
No clearance issues in a Dragon, of course.
One thing that's not been tested yet is the multi-bank support, so it might work in early Dragon 32s with 16 * 16K DRAMs, but I don't know that yet.
Edit: oh yeah here's Pedro's testing video
https://www.6809.org.uk/dragon/samx4/
Pedro's also designed a smaller version of the board, which is in the "rockyhill" branch in the gitlab repository.
He did come across a slight problem in his CoCo 2 during testing which I've noticed also affects my PAL machine: the SAM sits under the keyboard, really close, and the keyboard has a metal backing plate! Means the JTAG pins kinda need to be bent over to clear it, and even some shielding may be required... Maybe I need to get me one of those pogo pin programming cables...
No clearance issues in a Dragon, of course.
One thing that's not been tested yet is the multi-bank support, so it might work in early Dragon 32s with 16 * 16K DRAMs, but I don't know that yet.
Edit: oh yeah here's Pedro's testing video