I love my Instant Pot. It’s a slow cooker, it’s a pressure cooker… on Sunday I cooked three separate things in it. This is the middle one.

Gemsbok shin curry, recipe adapted from Food & Home’s Blesbok curry.

Instant Pot on saute, 20ml oil, fry one chopped onion for about five minutes. Add some ginger and some garlic, I use the little plastic jars from the Spar because I’m lazy. Add half a teaspoon or so chili flakes. Give it a few minutes.

Add 400 to 500g meat, in 1cm-ish cubes. Give it a few more minutes.

Add 1/2 tsp turmeric, 1/2 tsp cayenne pepper, 1 tsp ground coriander seeds, 1 tin chopped peeled tomatoes, mix it all up, let it simmer a bit. Add a couple cardamom pods and some cinnamon (I used about half a teaspoon ground cinnamon).

Add six to eight baby potatoes, halved.

Close the lid, set to pressure cook for 15 minutes, have a beer.

Depressurise, stir in about a teaspoon garam masala, let rest while you quickly rinse the pot and use it to boil some rice (2 minutes at pressure, maybe five minutes total).

 





6
May
'18

So I’m messing around with a Burroughs TD831 terminal which uses a 6800 processor, 8 kilobytes of DRAM and 16 kilobytes of mask PROM.

The PROMs are fairly typical of the era, in that the chip select lines are also programmable. So you program the first one in a bank of four to have two active low chip selects, the middle two ones to have an active low and an active high, as well as the reverse, and the fourth one to have two active high chip selects. That way you can run address lines into the chip selects and four PROMs act like one PROM four times the size, effectively.

How I figured this out: the PROMs have 24 pins, the largest 24 pin PROM is a 2732. Told my EXPRO that’s what they were, not much joy. Went down to 2716s, and that gave data out of one of each bank of four PROMs. I figured that this means the devices are similar to for example the 82S191. So it was time to write some code.

I was lazy and just told the code that the three potential chip select lines were address lines. This gave me a 16 kilobyte per PROM dump, three quarters of which is blank Looking at how the banks were located in the 16 kilobyte address space makes it look like pin 21 (A10 on the 82S191) is an active high Chip Select, while pin 20 is A10 and pins 19 and 18 are the programmable Chip Selects.

I suppose I can rewrite my code to map things that way, but I should be able to paste my dumps together into something that can be disassembled. If ever I am arsed to do that.

But if you are here on a quest to restore one of these things to life, I think I have given you everything you need in order to be enlightened.

Edit: You might notice that I did change the code and re-dump the ROMs in nice neat 2k binaries.