Blog · corpus.blog/blogs/michaeldoornbos.com/posts
michaeldoornbos.com
michaeldoornbos.com
2022
29 Jan 2022
It’s just before sunrise and I remembered that exactly 10 years ago today we jumped off a cliff. We uprooted our family from the DC suburbs and moved to the mountains of North Carolina. The view from our front door never disappoints even if you can’t really see the mountains this morning hardly at all.original ↗
29 Jan 2022
I have been looking for a physical copy of this book for some time. The cover on it is a little rough, but the rest of it is in okay shape and usable. SUPER happy to have found this. #commodoreoriginal ↗
28 Jan 2022
Occurs to me that using an Assembler on a Commodore 64 and then loading that program onto a KIM-1 isn't cross assembling. It's just assembling and loading. Not only isn't "cheating" but kinda feels good. #pedanticfridaythoughts #commodoreoriginal ↗
28 Jan 2022
Only have 1 RIOT chip until my second one arrives from overseas so had to modify the classic Asteroid by Stan Ockers (1976ish) for the KIM 1. Another surprisingly playable game on such a simple interface. Loading paper tape format files over serial from a real C64 ;-) #commodoreoriginal ↗
27 Jan 2022
Sooo many great programs to explore on the KIM-1. Spent a bit of time during lunch learning how the seven segments are wired. There is a surprising amount of example code out there with really clever techniques. KIM tribute to @8BitShowAndTell seemed appropriate #commodoreoriginal ↗
26 Jan 2022
Got conferences and shows coming up the next few months so my badge needs updating. Converted Style’s C64 fonts to binary format and I think I’m getting close on the correct screen colors. I think I’ll also implement a 10 PRINT demo on it #commodoreoriginal ↗
25 Jan 2022
Looking forward when I feel comfortable enough to do a 10 minute prototype for an idea on an FPGA platform. Microcontroller for now. Need to put in the work on learning FPGA better #therearenoshortcutsoriginal ↗
25 Jan 2022
Did a full restoration of my wife’s Grandfather’s TI-58C. They are notorious for bad ram and this one needed replacing. Also converted it to a DC wall plug. Now accepts assembly language programs and the built in functions work. Very cool late 70s tech. But .27 amps, yikes!original ↗
23 Jan 2022
I managed to enter all 196 Bytes of Lunar Lander by Jim Butterfield (BYTE April 1977) by hand with no errors on the first try. Such a fun game and a great way to learn 6502 Assembly programming the hard way. #commodore #shortcutsareboringoriginal ↗
23 Jan 2022
Got this KIM-1 replica together in a couple hours tonight. Was a fair bit of soldering but now I can computer like it’s 1976. 17 instructions to do a counter. Tomorrow morning we’re playing Jim Butterfield’s Lunar Lander on this thing! #commodoreoriginal ↗
21 Jan 2022
21 Jan 2022
Mentioned yesterday I've been going through this Math for Deep Learning book this week. The examples are all in Python, so I've been reimplementing every one in Julia. This not only gets me to really think about what I'm doing, but strengthens both my Python and Julia chopsoriginal ↗
21 Jan 2022
The Apple Lisa was released 39 years ago today. While it was a market failure it was crazy innovative. If you think about it, the computer you use today doesn't REALLY do anything more than this computer did.original ↗
19 Jan 2022
This group in my collection contains some really fantastic articles. April 1977 was one of my favorite issues of the whole BYTE magazine run. Never mind that I was 2 years old when it was printed ;)original ↗
18 Jan 2022
Well the fix was to reflow the solder joints around the connector. Must have had a cracked or marginal one. #commodoreoriginal ↗
18 Jan 2022
Hmm, getting a fault on my MiniPET 40/80 on the IEEE port. Anyone know if this needs a loopback to pass or is this really a fault? #commodoreoriginal ↗
18 Jan 2022
When picking up a new language (Julia this time), I like to solve new problems to get used to it or solve a problem I've solved in another language. Monty Hall will do nicely . Since Julia on an i7 is slightly faster than a 6502, I let the 64 do 1000 and Julia did 2^29 #commodoreoriginal ↗
13 Jan 2022
This 1977 game on the KIM-1 is surprisingly playable and really fun. A whopping 196 bytes. The number of things I’ve learned from Jim Butterfield is staggering. Something to think about as I write and try to contribute even a small thing here and there. #commodoreoriginal ↗
12 Jan 2022
Always wanted to add a python example the 100 Door problem article I did with the 8 Bit machines last year. Stumbled onthe fun Asciimatics library and then it was a snap.original ↗
11 Jan 2022
I’ve collected something like 30 calculators over the years. Most at least 30 years old. In the “modern” category I have 4 graphing calculators. In theory I should like the HP the most, but in practice the order of most to least used left to right is this. Even I’m surprised.original ↗
11 Jan 2022
Got the offending RAM off no problem but I just realized I don’t have a socket that will fit here. Off to mouser…original ↗
10 Jan 2022
In case you were just sitting there asking yourself “what DOES the inside of an HP-58c calculator from 1977 look like”original ↗
10 Jan 2022
I've been on Udemy for a decade and started but never finished many courses. And this is now the second one I've completed this week. Learn. All. The. Things.original ↗
9 Jan 2022
Creating a simple hello world DApp. Have I ever mentioned how much a loathe nodejs and Javascript in general? Urg.original ↗
9 Jan 2022
This is gonna need some work. My shots at 25 yards are consistently grouped like this which ain’t gonna cut it. Practice practice practice.original ↗
8 Jan 2022
So cool. Made a jet engine sounding cook fire with a handful of dry twigs. Science is awesome.original ↗
8 Jan 2022
8 Jan 2022
Doing a couple thousand-word article on the history and some usage of the Logo language, including code examples. Here's an example of some supporting stuff I'm creating for it. Fractal tree on Python (turtle) next to the same algorithm on a C64. Super fun. #commodore #pythonoriginal ↗
7 Jan 2022
I've signed up for 43 Udemy courses over the years. This is the VERY FIRST course I've EVER completed to the end. And… I'm planning to go through it from start to finish again.original ↗
7 Jan 2022
The Commodore 64 was introduced 40 ago at CES. You couldn't get one until about August, but you could argue that today is its 40th birthday. It was and continues to be a heavy influence in my career. This very C64 was in my bedroom for a decade. Still runs like a champ #commodoreoriginal ↗
7 Jan 2022
I love a program example that starts with "contrary to most available literature about USR…". This book is SO dense I have to go slow to keep from missing nuggets (rushing is dumb anyway). Like pulling the return address off of the stack at the end. SOOO GOOD. #commodoreoriginal ↗
6 Jan 2022
Okay, Julia's plotting syntax is SO much better. Kinda just fits the way I think without having to look things up. Might be my new goto language… #JuliaLangoriginal ↗
6 Jan 2022
Alright, resistors are all placed. I’m leaving two out until I decide if this is going to be a PAL or NTSC board. #commodoreoriginal ↗
5 Jan 2022
I’ve had this 250407 replica board for months and haven’t built it yet. Time to get started. #commodoreoriginal ↗
5 Jan 2022
I hate it when I break something that’s a result of my carelessness. And… I don’t have any spares. Sighoriginal ↗
5 Jan 2022
Okay, now I can clearly see why I'm going to keep learning Julia. Python took 18 seconds to do 100k iterations. Julia (almost identical code, definitely same approach) took 706 milliseconds. Dayuummm.original ↗
5 Jan 2022
Completely unscientific and meaningless benchmarks are fun. My favorite BASIC program of all time is this maze from 1981 originally written for the Atari 400/800 and the PET. Turbo BASIC XL sure does help the Atari 800XL be the machine it really is. Impressive. #atari #commodoreoriginal ↗
4 Jan 2022
These warnings exist because someone did it. I reserve ruining my broadheads by missing and hitting a tree… like a man.original ↗
4 Jan 2022
Seriously my new favorite album. Listening through my late 80s Boze speakers in my office all day. @lukhash is amazing. Does anyone want to sell me their Vinyl copy?original ↗
4 Jan 2022
Finally acquired an UnoCart (used, chip shortage and all that) for my Atari machines. Now I can properly try Turbo BASIC XL. This evening will be some completely ridiculous and shockingly unscientific benchmarking. #atarioriginal ↗
4 Jan 2022
Stealing my own Assembly code from my Enigma project for another project. Kinda love when you get to that point where you say "oh, I've done a bunch of the work for this already" #commodoreoriginal ↗
3 Jan 2022
Working on the next article in my "ciphers on old computer things" series and reviewing some supporting code for a couple of the articles I did last year. Very simple code here but the BASIC built-in string slicing routines are fast enough for many fun visuals. #commodoreoriginal ↗
3 Jan 2022
I think this is the first time I've ever used the BIT operator in my life. No longer a virgin ;-) #commodoreoriginal ↗
3 Jan 2022
Compute's BASIC Toolkit book example 3 is passing parameters to SYS. So satisfying to be just getting into the weeds with 412 pages to go in the book ;-) #commodoreoriginal ↗
2 Jan 2022
My linear algebra is really rusty so I'm going back and reviewing today. SO much better if you can visualize along the way and the tools for this these days are crazy good. How can you not love open source and the people who pour themselves into these libraries?original ↗
2 Jan 2022
Still not decided on Assemblers on the VIC-20 so just doing it in the monitor for now. #commodoreoriginal ↗
1 Jan 2022
Cold front will be here soon, so putting some miles in. We moved here 10 years ago this month and I still have to pinch myself that we live here.original ↗
1 Jan 2022
I'm planning to go through this book this year on the 64 and VIC-20 at the same time. It may very well take me a good part of the year, but there really aren't shortcuts to anything worth doing. Means I need to re-evaluate VIC-20 assemblers again which is fun. #commodoreoriginal ↗
1 Jan 2022
I eat broccoli sprouts by the fistful. If you grow then at home a quart costs like 3 cents.original ↗
1 Jan 2022
Might not seem like much, but set out at the beginning of the week to get past the raw beginning stages of FPGA development. Button presses, LEDs, seven segments, counting… check. Super happy with my progress.original ↗
1 Jan 2022
2021
Spending some time learning @JuliaLanguage this week. Just realized arrays are 1 based instead of zero. I don't know Julia, this new relationship might not be working for me.original ↗
31 Dec 2021
Went the fairly traditional route to get this @lukhash program from the album onto my 64. Played it onto a tape and into the datasette. Other than having to hook up one my PAL 64s, was a snap. Very very cool. But I NEED this on Vinyl now ;-) #commodoreoriginal ↗
30 Dec 2021
This finally arrived today. I was disappointed the LP was sold out when I ordered it back in November, but having it on CD does make it easier to get the bonus track, a Commodore program, onto my C64 so there’s that. Awesome artwork @lukhash #commodoreoriginal ↗
30 Dec 2021
Challenging by myself to do this part, but got the elevator on today and it has all the right clearances for good movement. Now to balance it. #myzenith750original ↗
30 Dec 2021
Change of pace for the build today. Working on the interior which is currently a hot mess. #myzenith750original ↗
30 Dec 2021
Adding @JuliaLanguage to Jupyter is easy, but it's interesting that labs still calls this an ipynb by default which can't be right…original ↗
29 Dec 2021
It’s raining, so back inside this afternoon. In the interest of keeping to my principals, switching to a Lattice FPGA since at the moment it’s the best if you want a 100% open source tool chain. My Alchitry CU will do. BTW Digikey looks to have iCEsticks available mid Janoriginal ↗
29 Dec 2021
We started this puzzle on Christmas morning. She just put the last piece in place. Julie did about 80% of it :)original ↗
29 Dec 2021
Taking a break from FPGAs this morning to get the 5 of these I bought earlier in 2021 up and running. Got a lot of uses for these.original ↗
29 Dec 2021
Great first day progress learning FPGAs. Seven segment display counting from a Xilinx Artix 7 in Verilog and I even understand what's happening which makes it even sweeter.original ↗
27 Dec 2021
My bow is 32 years old. It has zero fancy features. Shoots true. I’m finding many things in my life that I prefer to have less features.original ↗
27 Dec 2021
I’m off all week and not a “relaxing is actually relaxing” kinda guy. I bought this a year ago and always meant to really get into FPGAs. No time like the present.original ↗
27 Dec 2021
Easily my favorite food and stupid easy to make. Somehow I scored this at $6 per pound last week.original ↗
25 Dec 2021
One of my favorite Christmas gifts… my wife found an unopened vintage Mastermind from the early 70s.original ↗
25 Dec 2021
My twitter account was locked for this tweet which contained only a video of my own code. No music, nothing offensive.original ↗
24 Dec 2021
Definitely have the hang of Logo on the C64 now. Since it's Christmas eve, I'm calling challenge from @101Computing done for now. I'll do more snowflake leg randomization here and there, but was fun to play with Logo this morning. #commodoreoriginal ↗
24 Dec 2021
Yet another rabbit hole I'm down thanks to @8bitshowandtell. Been REALLY enjoying this book and through some patience (okay, A LOT...took like 6 months) I acquired a physical copy for less than highway robbery. #commodoreoriginal ↗
23 Dec 2021
After quite a bit of work, I'm now getting a VERY good video signal out of this VIC-20(PAL). Even my cheap video capture device does a good job with it. #commodoreoriginal ↗
23 Dec 2021
Today's beginner python challenge from @101Computing is a randomized snowflake challenge with Turtle. Since I'm not a beginner in Python (25 years), I figure Logo on the Commodore 64 was not cheating. Should be fun. #commodoreoriginal ↗
23 Dec 2021
Just pulling this one out of storage. It was my wife’s grandfather’s who was an aerospace engineer at Lockheed. Works great but needs a bath. Am I reading this price tag right?original ↗
22 Dec 2021
Six month check on my Vicky-20 build: I’m going to either have to remove and replace most of the precision sockets or figure out a way to hold the chips in. Every few days the ICs work their way out. Maybe zip ties? Double wipe sockets for me from now on. Sigh. #commodore #vic20original ↗
22 Dec 2021
This HP32SII has been in my bag every day for about 25 years. Simple, rugged and powerful. But this HP Prime is really growing on me… hmmm.original ↗
21 Dec 2021
Working on "cracking" simple ciphers on old computers next. Letter frequency, then word frequency. Step one works well enough #commodoreoriginal ↗
21 Dec 2021
21 Dec 2021
Permutations of 1 to 9 in Assembly/Machine Language, BASIC, and Python. It only took 30 hours in BASIC ;-) (Python was 2 seconds without optimizing) You know, for science https://imapenguin.com/permutations-of-1-to-9-in-6502-assembly/ #commodore #pythonoriginal ↗
20 Dec 2021
Sonic for the C64 is out today. I happen to have a 64C in my collection that's PAL. So combined with the UltimateII+, its 1581 drive, and 16MB REU, this game runs very very well. #commodoreoriginal ↗
19 Dec 2021
Some people watch TV, I sort out graph theory concepts in a machine code monitor with my “laptop”. Like what you like and don’t apologize for it. #commodoreoriginal ↗
18 Dec 2021
I was just thinking that this morning instead of being productive or doing holiday stuff I’d count how many times I can unintentionally hit the CAPS and break keys. #atarioriginal ↗
18 Dec 2021
I really enjoyed Nick’s “Racing the Beam” so I figure this will be my next weekend reading.original ↗
17 Dec 2021
Can you do #adventofcode with 40 year old machines? The answer is “some of it”. Even counting takes a long time, let's get into some of the details. https://imapenguin.com/can-you-do-advent-of-code-on-8-bit-machines/ #commodoreoriginal ↗
14 Dec 2021
Finally getting back to writing up some of the ciphers I’ve done but not yet published. Only took like a 5 month break (detour?) Tomorrow I’ll post the VIC Cipher on the VIC20 which does just barely fit on an unexpanded VIC. #commodoreoriginal ↗
13 Dec 2021
Hard not to be in awe of nature sometimes. These burrs are particularly good at clinging to sweatshirts.original ↗
12 Dec 2021
I have been doing Breadth and Depth First Searches on Apple II and Commodore for a couple months, so Day 12 of #AdventOfCode was doable (but slow) on a C64. END is a keyword in BASIC so I changed it to FIN #commodoreoriginal ↗
12 Dec 2021
We bought a whole Mangalica pig from a local farm, used a local butcher. Having the whole animal means you have to use scraps, everything. Made some “cottage bacon” with some pieces and happened to have decent ingredients for an English breakfast (dinner).original ↗
9 Dec 2021
For #AdventOfCode Day 8 Part 2, figured it out in Python first to wrap my brain around how to do it iteratively. After an "ah ha" moment in sorting the unique segments it clicked. Python: 0.04 seconds and PET: 25 minutes.I could refactor it to be faster but not bad. #commodoreoriginal ↗
8 Dec 2021
Still having fun doing these #AdventOfCode puzzles in the morning. I changed the delimiter from "|" to a zero since old computers don't always have that character. Part one was a lot of data, but the PET got through it pretty quickly. #commodoreoriginal ↗
8 Dec 2021
Something interesting I like to do on these long calculations is to compare machines to the fastest Commodore computer, the PAL VIC-20. In this case, the VIC-20 finished 48 minutes sooner than the NTSC C64. Very scientific of course 😉 #commodoreoriginal ↗
7 Dec 2021
Part 2 of #AdventOfCode Day 7: my rough estimate is that my current code will run for… well a LONG time on a lowly #C64. So what to do… I know! Run the exact same code on BBC Basic on a 2.6Ghz i7 in 60 seconds ;-) Cheating? Maybe. Am I happy anyway? Yes #commodore #BBCBASICoriginal ↗
7 Dec 2021