Blog · corpus.blog/blogs/michaeldoornbos.com/posts
michaeldoornbos.com
michaeldoornbos.com
2023
I’ve completed all 25 days of #adventofcode the last 4 years. Last year I did about 1/3 of them on my Commodore PET 2001. Sometimes the data was too unruly to try to get onto it so for those I resorted to Julia. Should I use the PET again this year or a different 8 bit computer?original ↗
27 Nov 2023
I take excellent notes, but every once in a while, I'll take something out and stare at it wondering... where is the CPU for this one, and why did I take it out?original ↗
27 Nov 2023
In case you were just sitting there wondering... C64Forever/AmigaForever seems to run okayish in Whiskey on an M1 Mac.original ↗
26 Nov 2023
A little light ARM assembly reading this morning. And yes, we have three Christmas trees. You’re not the boss of us.original ↗
26 Nov 2023
Got a fun emulator project in the works with a mechboard. Since the keycaps are breadbin colored I went with the breadbin colored case even if it’s not traditional for the C64c case.original ↗
25 Nov 2023
I keep seeing this 1982-3 ad of a Commodore 64 in a briefcase. It DOES, in fact, fit in a standard-sized briefcase, although I'm not sure I know why I would have wanted to.original ↗
24 Nov 2023
10print on the TI-nspire. Also Python and feels like cheating. Still fun though. Happy Friday!original ↗
24 Nov 2023
Happy thanksgiving in the US. For Today’s 10PRINT the @NumWorks calculator has Python instead of Basic and I got it on one line even if it’s hard to read like that. This calculator sure is fast!original ↗
23 Nov 2023
A little Thanksgiving week fun. Here's 10PRINT on a TI-92. I couldn't find a way to escape a new line, so I tried a different approach. Also, iPhones have difficulty locking focus on this screen.original ↗
22 Nov 2023
Has anyone considered that maybe the AI is coordinating the board coup at OpenAI? Where are my wire cutters?original ↗
20 Nov 2023
A little sanity/verification that my two's compliment circuit is working. It is, and it was without any debugging, which freaks me out. Happy Monday!original ↗
20 Nov 2023
Okay, I'm putting the C128 away and going to my happy place. I've always wanted to love the 128 but give me a VIC-20 or C64, and that's where I'm truly happy.original ↗
19 Nov 2023
A little Friday night VIC-20 VIC chip replacement fun. Finally getting around to NTSC. My test bench looks right for the clocks I need to generate. Wild and crazy around here on Friday nights ;)original ↗
17 Nov 2023
These ROMs have 8 switchable ROM images on them. And by using a rotary switch to select them, you can play Russian roulette. Which ROM did we get this time, Dad?original ↗
16 Nov 2023
16 Nov 2023
Sometimes, I've just got to step away. Went to build my FPGA test bench, and now GTKWave on my Mac needs an obsolete module from an ancient Perl version to launch via the command line. I give up for today. The VIC-20 video test will have to wait. Sigh.original ↗
15 Nov 2023
When I sit and think about WHY I'm building a VIC chip drop-in, I sometimes lose sight of the goal. But just today, one of the CIAs on my Commodore 128 died. So happy for products like the J-CIA. This 128 has many drop-in replacement parts and is a good motivator.original ↗
13 Nov 2023
A donated 1541 with nice VIC colors. It does work but the fuse holder is broken and there’s a scorch mark next to it. Might replace it with modernish power supply after I thoroughly clean it. Cool to have a long board variant.original ↗
11 Nov 2023
Designed a simple demo in Logisim, which worked great. But it's not nearly as satisfying as making it for real. So... out comes the breadboard. I wonder if I can make the wires neat... probably not. Happy Friday!original ↗
10 Nov 2023
9 Nov 2023
7 Nov 2023
The Mechboard64 does not work out of the box with a KeyRah v3. I did figure out a workaround so I’m going to write up some detailed instructions in case anyone else wants to put these two things together. VIC-20 colored keycaps for me of course.original ↗
6 Nov 2023
Looking forward to when those new keycaps will be available again. I CANNOT bring myself to cannibalize a perfectly working original C64 keyboard for this.original ↗
4 Nov 2023
4 Nov 2023
I love these things but it took a long time to get here. Going in a Breadbin tonight in time for some holiday tunes.original ↗
3 Nov 2023
3 Nov 2023
I have tried several 80 column solutions. The RGBtoHDMI by @TexElecUSA is the best by a long shot. Happy Friday!original ↗
3 Nov 2023
Saved my #NaNoWriMo2023 work to a 5.25 today to keep @GetOuttaHeah from yelling at me for using modern stuff like 3.5 inch floppies. Happy Thursday!original ↗
2 Nov 2023
Both of the programmer calculators I have are missing y^x functions. At least on the HP-16C I can write a short program to do that. I use y^x more than the average bear. Still like this Casio a lot though.original ↗
1 Nov 2023
My post earlier about writing on a KIM-1 by typing in hex ASCII codes by hand was a joke, obviously. My real distraction-resistant writing platform for #Nanowrimo2023 is my HP t5710 Thin Client running FreeDOS and WordPerfect 6. Just for fun, I'm going to save my work on floppiesoriginal ↗
1 Nov 2023
Alight @8BitShowAndTell, challenge accepted. Until 3 minutes ago I wasn’t even sure the 128 had the Kernal routines for the Datasette.original ↗
31 Oct 2023
Working on my distraction free #NaNoWriMo setup. Using this table I’m up to typing as fast as two words a minute. If I don’t sleep, there’s 43200 minutes in November so I can hit the 50000 word goal for the month of I account for the inevitable going crazy from lack of sleeporiginal ↗
31 Oct 2023
My copy of David Youd's book came today. I had already implemented $3A earlier this week, which timed nicely with my n-queens implementation in BASIC. Pretty fun!original ↗
25 Oct 2023
Untested 1541. Just spins and spins. I’m sure this capacitor came from the factory like that :)original ↗
23 Oct 2023
That is quite the clever hex-to-decimal converter for the 6502. Embrace constraints and happy Friday!original ↗
20 Oct 2023
The N-Queens problem feels easier to understand and more fun to implement on old computery things.original ↗
12 Oct 2023
It's October, so Halloween themed Zoom meeting help is in order. Just in case this game wasn't hard enough, try the Commodore 64 version on a joystick with a single button. Jump is up... so hard like this.original ↗
2 Oct 2023
30 Sept 2023
Solving the 8-queens problem on a Commodore 64. I won't leave it in the final version, but sometimes it's fun to print the output of loops to watch your backtracking algorithm work. Happy Friday!original ↗
29 Sept 2023
27 Sept 2023
On my morning walk/hike and I just saw a bear run through that foggy area. I think I will turn around a little bit early this morning.original ↗
26 Sept 2023
These are the two keyboards in my office. Both brown mechanical switches and are fantastic to type on, but the fact that they have different arrow key layouts really trips me up sometimes. Anyway, happy Monday!original ↗
25 Sept 2023
Some people say my 35 year old bow should be retired. New bow technology is better or some nonsense. The secret to archery is in the archer, not the bow. That’s why I shoot better than you, whipper snapper.original ↗
23 Sept 2023
Still my best distraction-resistant writing setup. FreeDOS, Wordperfect 6.22, mechanical keyboard with brown switches on an HP t5710 thin client (they make GREAT DOS machines).original ↗
22 Sept 2023
I'm stuck on something in my day job. Gonna switch gears and do some therapy, back to implementing Enigma 8-bit style. Where we're going, there's gonna be a lot of assembly coding ;-) Happy Fall!original ↗
21 Sept 2023
I read every single page and typed in every single line of code in both of these books. Something I told myself I would do when I was a kid, but you know kids. Definitely worth the effort.original ↗
20 Sept 2023
18 Sept 2023
GM touch screens are comically unreliable. Dealer wanted $800 to fix it. A little parts research, Torx bits and a heat gun and I did it for $34 in an hour. New touch screen is all shiny. Hack the planet.original ↗
16 Sept 2023
I'm trying to decide if I knew you could do this in MS style BASIC before just now or not. Surely I did right?original ↗
15 Sept 2023
Found this receipt in this book being used as a bookmark. Decided to keep using it as a bookmark. Happy Friday!original ↗
15 Sept 2023
Had a lot of fun learning TI Extended BASIC for the TI 99/4A to port a Rail Fence Cipher from my Commodore 64 version.original ↗
8 Sept 2023
Alright, the TI 99/4A is really growing on me. Decided to get my hands a little dirtier and write a simple Cipher in Extended BASIC. There is a lot of string manipulation in Cipher work. Commodore version, side by side, and article tomorrow. 34 lines of code, easy peasy.original ↗
7 Sept 2023
One issue with the TI fixed. Cassette interface now good to go. I have another cassette player around here somewhere with a counter on it which would be useful. On to what’s wrong with the cart port.original ↗
5 Sept 2023
Slowly undressed the TI 99/4a… made bow chica wow wow sounds while I did it. Cassette interface and cartridges don’t work. Time to find some schematics.original ↗
3 Sept 2023
2 Sept 2023
Whelp, it's #Septandy. Since I only have Cocos, we'll see how long I can look at the soothing toxic green before turning into a Ninja Turtle. Is it #VICober yet?original ↗
1 Sept 2023
More Septandy prep. Still my least favorite line of retro computers to actually use but I’m gonna try to find some parts to love.original ↗
30 Aug 2023
Tandy Coco 1 keyboard: it’s nice and clean inside but the plungers on this side are mechanically difficult to press and get hung up. Ideas?original ↗
30 Aug 2023
Without using TI Extended BASIC (yet), this is the shortest I've managed a 10 PRINT on a TI 99/4A. It's not 1 line, but it's easy to understand and has the advantage of making any two characters you want quickly on the fly to randomly print.original ↗
30 Aug 2023
Attempt #3 of 10 PRINT on the TI 99/4A: While a far cry from the elegance and simplicity of the Commodore 10 PRINT, this version at least got me to learn how to redefine characters on the fly and make it look much better.original ↗
29 Aug 2023
Take number two is even uglier so I decided to do it a second pass vertically. It's also super slow which is... nice... Next I think we redefine some characters to at least make the "maze" look better. If we can't make it fast or even close to one line, we can at least put some lipstick on it.original ↗
29 Aug 2023
Playing around a little with TI 99/4A BASIC. It's different than what I'm used to, but I do like the IF-THEN-ELSE. Here's try #1 at a 10 PRINT program. Surely we can do better than this.original ↗
29 Aug 2023
Always a good morning when there's @8BitShowAndTell Turbo Macro Pro code to study and contemplate. Happy Tuesday!original ↗
29 Aug 2023
Traded a Coco2 for my first TI-99/4A "untested." I don't have direct experience with TI hardware. Assumed my experience meant I would be able to fix whatever might be wrong. It works just fine, which is slightly disappointing because I love restoring old computery things.original ↗
24 Aug 2023
I was a guest on @8BitShowAndTell's last video (https://www.youtube.com/watch?v=JTxiR4ZKfvo) and in it he gave me a new title. This is a longstanding inside joke between Robin, @DarrenFoulds and me from their 80s podcast (which is on a break). I decided to make it official by getting it in print.original ↗
23 Aug 2023
I’m about a year into the DM42 replacing my 32SII that was my daily driver for almost 30 years. Hard to argue with how well that HP stood up to being abused in my laptop bag all that time and still works like a champ. They don’t often make ‘em like they used to.original ↗
22 Aug 2023
Had these two books on my shelf as a kid. Always thought that I should spend the time to understand them. At 11, self-discipline was hard. I might be late, but just finished the first one. Every page, every line of code. Starting the second tonight. First principles is the way.original ↗
14 Aug 2023
I’m trying to imagine getting my VIC replacement even close to the size of this thing. Really impressed.original ↗
12 Aug 2023
Just another random stretch of my daily walk. This is the only flat part. I’ve been doing more or less the same 3.5 mile walk 3-5 times a week for 10 years. It wasn’t until I took out the headphones and stopped tracking my health stats that it became really transformative.original ↗
10 Aug 2023
I don't think Forth is some closet technology waiting for its moment. But it makes me think about problems differently, so I continue studying it.original ↗
9 Aug 2023
8 Aug 2023
Many asked about making the grid with the stock BASIC. It can be done, and is even fairly straightforward, but it's awfully slow (40 minutes). Still fun though.original ↗
7 Aug 2023
French Broad was low today. Julie led most of the way for about 6 miles as we picked our way through the rocks.original ↗
6 Aug 2023
It's rumored that @elonmusk's first computer was a VIC-20. I thought doing the logo would be easier than it turned out to be, but it's still just 10 lines of code, thanks to Super Expander. #commodore #vic20original ↗
5 Aug 2023
5 Aug 2023