Blog · corpus.blog/blogs/michaeldoornbos.com/posts
michaeldoornbos.com
michaeldoornbos.com
2022
20 Sept 2022
18 Sept 2022
14 Sept 2022
I don’t understand the TV in the bathroom at restaurants thing but I’m at a taco place on Florida that has one. Princess Leia watching you pee is unsettling.original ↗
13 Sept 2022
Long tree searches on a Commodore 128. Some things are better explained and learned on older hardware. Easier to see what’s happening and feels less like magic.original ↗
13 Sept 2022
Traveling to Orlando this week for work. Want to be in the right mindset for the rest of 2022, so this new book is my theme for the week.original ↗
12 Sept 2022
I sold my airplane project and I feel really good about it. An enthusiastic guy outside of Charlotte bought it. I don’t subscribe to the “you must finish a book because you started it” type philosophy.original ↗
11 Sept 2022
Workout done before 6am, so might as well move to some light reading. Much of this book I practice every day already, but getting the basics right is always a good plan.original ↗
10 Sept 2022
I suppose it IS #septandy so I can spend 15 minutes this year with my Coco 2. Soon it’ll be #victober and all will be right with the world. Until then….original ↗
9 Sept 2022
Why would they take a clean, natural, healthy food and turn it into an artificially flavored bastardization?original ↗
7 Sept 2022
7 Sept 2022
7 Sept 2022
31 Aug 2022
I’ve been using a modified version of Ryan Holiday’s notecard system for a week and it’s already transformative. Analog for the win.original ↗
30 Aug 2022
30 Aug 2022
30 Aug 2022
29 Aug 2022
Sometimes the Sunday project chooses you. New water heater since the old one tried to flood the basement. Basic dude stuff.original ↗
28 Aug 2022
27 Aug 2022
This game came pretty late in Commodore 64 history, but I'll never forget the look on my younger brother's face when he first saw it. And yes, the gameplay is still really awkward with a lack of mouse on the 64. Happy Friday!original ↗
26 Aug 2022
25 Aug 2022
We collect many old cookbooks. This gem from 1942 has a wartime supplement section and tips on a healthy weight. Example, a 5’8” thirty year old man should not be more than 154 pounds. Also sections for things like box lunches for “hard workers” and “a business girl”. Fun read.original ↗
21 Aug 2022
Breaking in a C64 repair I did for a local friend with my favorite 8 Bit Maze generator. This one never gets old. Happy Friday! #commodoreoriginal ↗
19 Aug 2022
18 Aug 2022
18 Aug 2022
Just in case this game wasn't hard enough... try it on a Commodore with a single button joystick. Decrunching to the REU is a nice add on :-) #commodoreoriginal ↗
18 Aug 2022
Adding the Genie framework to my @JuliaLanguage toolkit. The OscarsExplorer example is pretty neat.original ↗
12 Aug 2022
Everyone has 3 keyboards on their #Commodore PET clone right? No? Just me? Okay then. #WoodPET buildoriginal ↗
11 Aug 2022
Multiple Dispatch is kinda @JuliaLanguage 's super power. Never really grokked it until I followed this example. Mind explodey.original ↗
10 Aug 2022
Pretty happy with the way this turned out. 5 coats of acrylic should hold the vinyl on the keycap labels. A PET with Cherry Black switches is a PET you could even write a novel on :) #commodoreoriginal ↗
9 Aug 2022
8 Aug 2022
8 Aug 2022
6 Aug 2022
As a long time Commodore guy, I've under appreciated the Apple 8Bit computers. Really quite amazing for the early 80s. This took just over 3 hours. Happy Friday!original ↗
5 Aug 2022
Still testing the timing with the W65C02S-14 running on this VIC-20. Super expander cart seems to be fine and it can do math well enough. 90 minutes to complete this isn't bad for 1981. #commodoreoriginal ↗
4 Aug 2022
4 Aug 2022
The VIC-20 palette voltages are kinda tricky. For this alpha version of the project I’m just going to have to be okay with this particular background blue for now. Funny, if you pick up 470 ohm resistors out of the box instead of 270 how much trouble you can make :) #commodoreoriginal ↗
3 Aug 2022
Probably only funny to me… I was working out some resistor ladders for the VIC replacement project and got two values wrong. Think anyone would mind #commodore 64 colors on their VIC-20? Happy Wednesday!original ↗
3 Aug 2022
I wonder if there's any value in writing a VIC chip and 6502 protocol decoder. Hmmm #commodoreoriginal ↗
3 Aug 2022
New stretch goal: get the most accurate pixel timings on VIC-20s possible with equipment I already have. We'll have to resort to... dun dun dun... math! #commodoreoriginal ↗
2 Aug 2022
Before day job two steps back on the VIC replacement project: since PAL was progressing nicely I switched to NTSC to catch up but broke something along the way. Hmm… that isn’t right AT ALL #commodoreoriginal ↗
2 Aug 2022
I’ve always wanted an original Commodore PET 2001, but they are now crazy expensive. What’s a guy to do? I’ll just make one :)original ↗
31 Jul 2022
Today marks the first time in history that a human has managed to wrestle a tent back into the bag they sell them in. Rainy day garage projects…original ↗
31 Jul 2022
This might be my favorite thrift store find to date. And it’s fully working. We will add all the things.original ↗
30 Jul 2022
No one is ever going to accuse me of being good at surface mount soldering. But they are at least on and it works :) #commodoreoriginal ↗
29 Jul 2022
My all time favorite book is $1 at the thrift store. Never mind I already own like 7 copies…original ↗
29 Jul 2022
I'm still SUPER tempted to use VGA instead of composite for the VIC-20 VIC replacement. Much of this is known but in multiple places. Probably will make a dedicated page for all of the calculations I do for myself. If others can use it, then cool. #commodoreoriginal ↗
26 Jul 2022
Replaced the 65c02s adapter on the Vicky Twenty with @shieladixon’s board of who was very kind to send me a couple from the UK with a nice note and postcard. Not using a transceiver seems to be working fine on this board and definitely takes up less space. #commodoreoriginal ↗
26 Jul 2022
Fixing a friend’s VIC-20 and I hastily assembled a character ROM adapter. I then spent an embarrassing number of Mississippi’s wondering why it didn’t work. Details Michael, details. #commodoreoriginal ↗
25 Jul 2022
Good grief, these are still waaayyy too long. I’m gonna have to break down and buy an IDC cable connector crimper. Until then, let’s get the VIC-20 memory map more organized in my Verilog shall we? #commodoreoriginal ↗
22 Jul 2022
Back on the VIC chip FPGA replacement this evening after a needed break. Having to level shift both directions between the VIC-20(5V) and the FPGA(3.3V) is a recipe for a crazy breadboard mess. Working on tidying it up. Looking better already.#vicsrevenge #commodoreoriginal ↗
21 Jul 2022
21 Jul 2022
This is what I settled on for the @TexElecUSA #commodore PET keyboard arrangement using ANSI 104 keycaps. Now I need to get stickers printed but I’m very happy with the way this is turning out. Went with Cherry MX blacks on this one.original ↗
20 Jul 2022
Today’s side quest: take these 208 ANSI keycaps and come up with a reasonable arrangement for my #commodore PET replica keyboard. Should be interesting.original ↗
20 Jul 2022
14 pounds (not a typo) of the last of the local Mangalitsa we bought over the winter is spending all day on my ancient, beat up, hand me down smoker. It’s a hard knock life. :)original ↗
17 Jul 2022
15 Jul 2022
More CPU testing. The 65c02s with the transceiver is consistently slower. Gonna have to break out the scope and look carefully at timing and propagation delays. Same machine, same code, different CPU setups. #commodoreoriginal ↗
14 Jul 2022
Had my romulator for about a year. Unfortunately came pre assembled with square header pins which are VERY hard on sockets. Anyone have any adapter ideas for square headers? Can’t get them off without removing the cpu socket so I’m reluctant to desolder 80 pins if I can help itoriginal ↗
14 Jul 2022
Fun with strings anyone? Making and breaking codes Part 14 - VIC Cipher on the unexpanded Commodore VIC-20. Who needs more than 3583 Bytes of Memory? Not this guy. #commodoreoriginal ↗
14 Jul 2022
Alrighty this VIC-20 is now running a brand new WDC65C02S manufactured recently thanks to the @AtticThe adapter. Now the only part left without an easy to source or modern replacement is the VIC chip. I did hear some nutball is making a replacement for that though. #commodoreoriginal ↗
13 Jul 2022
Took me a minute to figure out what these are. There’s a 100 foot section of my daily walk lined by Rugosa roses. Sometimes called potato roses. Can’t wait to see what they look like when they bloom.original ↗
13 Jul 2022
Been using these in one form or another for 40+ years and still not remotely tired of them.original ↗
13 Jul 2022
RGB green for the win! The real reason for the RGBtoHDMI purchase is for my MiniPET case build. Currently code named WoodPET. Coming soon to theaters near you. Er, my office. One of those. #commodoreoriginal ↗
11 Jul 2022
I have tried about a half dozen solutions to get reasonable color 80 columns out of my flat Commodore 128. The RGBtoHDMI is hands down the winner here. #commodoreoriginal ↗
11 Jul 2022
Most asked question of the drop in VIC chip replacement is: when will I be able to buy it. The trick is that I would be TERRIBLE at supporting a “consumer” product. Apparently “I find you too annoying to answer this question” is not a good tech support response. #commodoreoriginal ↗
10 Jul 2022
Friday VIC chip replacement progress: this is an NTSC VIC-20 without a VIC chip (or internal clock) running as PAL off of the FPGA (clocks and video)outputting composite correctly. No RAM access yet, but I'll take a square box at this point. Happy Friday! #commodore #vicsrevengeoriginal ↗
8 Jul 2022
6 Jul 2022
Not that I'm surprised… I need ONE 74HCT245N for a @AtticThe adapter. Do I have one in my huge parts inventory? Not one. But if you need 74LS245Ns, I'm your guy. Mouser has 12,500 back-ordered until May 2023. Sigh. #commodoreoriginal ↗
6 Jul 2022
Not that I need another project, but I’ve been gathering things I need to make a PET 2001 replica out of wood. Working chicklet keyboard: check. Gonna disassemble and do a restoration and preservation session. Anyone have one that can measure the case for me? #commodoreoriginal ↗
6 Jul 2022
Deep woods #Vicsrevenge VIC drop-in FPGA progress: Finally have an internal pixel clock 4.434Mhz driving a composite (no color yet) pulse with the correct timings for a 2µs character width (225.5ns per pixel). Probably doesn't seem like much but it matters a lot to me #commodoreoriginal ↗
5 Jul 2022
When I said “drop in VIC replacement” did you take that as “true to the original in every respect”? Because Composite video with the VIC-20 colors is a royal PIA. VGA is much more easier. I know, I know, there are no shortcuts. This is also why I gave myself a year. #commodoreoriginal ↗
3 Jul 2022
Finally got me some real (r@re) punched paper tape. Actually have no idea what’s on these so I’m gonna have to break out the worlds worst paper tape reader to give it a go.original ↗
2 Jul 2022
Lived here 10 years and gone for a walk 4-5 times a week (including winter). So I’ve probably come over this hill 2000+ times. Still not tired of the view around here. Happy Saturday.original ↗
2 Jul 2022
Wow this book arrived crazy fast. Guess the Apple IIe is the vintage machine I’m keeping on my desk for July.original ↗
1 Jul 2022
I need an ESP32 that's like an Arduino Mega. Can I have like 60 usable GPIOs please? Sigh.original ↗
1 Jul 2022
I'm a decent 6502 assembly programmer (milage may vary) so I figured hopping onto an assembler on the Apple II would be a snap. It is... except I never learned ProDOS... got hung up there. Much reading and now I'm comfortable. #appleiieoriginal ↗
30 Jun 2022
Taking a break from a VMWare certification to have a little Apple IIe fun. I don't have a color monitor (my Apple monitor is Green) so to get color I HAVE to use my capture setup. Works pretty well ;-)original ↗
30 Jun 2022
Designing composite video in FPGA for the 6560/1 VIC replacement project #vicsrevenge... this might be the most useful visualizer/synthesis tool I've ever seen. Load your Verilog and get a visual representation AND what amounts to a test bench setup. Brilliant! #FPGA #commodoreoriginal ↗
28 Jun 2022
Today's side quest is to get back into computer vision. Might was well kit-bash it with reading paper tape right?original ↗
28 Jun 2022
A year later and I finally soldered the keyboard header pins in. Coming soon :) #commodoreoriginal ↗
27 Jun 2022
I need the 80 column mode on my 128 for a long number project this week. July is my scheduled maintenance month for this machine so I might as well do that first since I have it out. No retrobrighting happens in my shop. This thing earned it's yellow ;-) #commodoreoriginal ↗
27 Jun 2022
I forgot that I have this butane powered soldering iron. Very convenient for a single quick job. Gotta keep it in mind.original ↗
24 Jun 2022
I needed some window tint for the overhead window in the airplane, and it’s just a bonus that it is just the thing you need on a KIM-1 (clone) to increase the visibility of the LED display. Before and after is pretty stark. #commodore #kim1original ↗
20 Jun 2022
Pulled out the FabGL board. Apparently I was running Windows 3.0 last time. Seemed more fitting to turn it into a VIC-20. And what’s the first game on the list in the distribution? Splatform by @8BitShowAndTell… That guy sure gets around #commodoreoriginal ↗
20 Jun 2022
Squeezing @BrunoLevy01's RISC-V core onto an Icestick #FPGA is a lesson in "you really can do a lot with just a little". So many lessons to be learned. At 50Mhz Pi and Mandelbrot work really well. I'll leave the Icestick permanently hung off of this Raspberry Pi from now on.original ↗
20 Jun 2022
19 Jun 2022