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Hack Chat Transcript, Page 1

A event log for 6502 Hacking Hack Chat

Making 8-bits matter

tom-nardiTom Nardi 04/03/2024 at 20:440 Comments
Anders Nielsen  3:00 PM
Thanks Dan! Hello everyone! Super excited to answer any questions. Really been itching to jump in ahead of time By day, I'm the MacAdmin at Aalborg University, Denmark, handling about 1000 Macs. In my free time I like to play with old and new IC's and to get as much as possible out of as little as possible - most fun per transistor or most fun pr $ are favorites of mine. I've played with electronics since 2014.. or since early childhood if disassembling anything with a battery counts.. I made my first 6502 computer in 2021, followed it up with an entry for the 2022 Hackaday Prize, and was super happy the to see that go to the semifinals. Since then I've made the 65uino, which is a lot easier to manufacture and put together, but has it's own limitations - like the 8K address space and 128 bytes of RAM. Like an Atari 2600. And I almost have a PCB ready for a super super cheap (E(E))PROM programmer.
Anders Nielsen  3:00 PM
Oh - and I have a small Youtube channel where I try to explain most of the things I make, so it's easier for other people to replicate.
Anders Nielsen  3:01 PM
But ask away - I'm not an expert on any of it though.. Except my day job.
Dan Maloney  3:02 PM
Was the 6502 a nostalgia play for you? IOW, did the chip feature in any of the machines of your younger days?
Anders Nielsen  3:03 PM
Absolutely. When I was a kid in the 90s I had a C64 but I didn't have any of the knowledge to actually use it for anything but games.
wheagy  3:03 PM
Do you ultimately expect this to be a drop-in replacement in machines like the Apple II?
Anders Nielsen  3:04 PM
The Apple II should accept mostly any old NMOS 6502 I believe?
Andy Geppert  3:06 PM
The 65uino is awesome and very inspiring. Thanks for imagining and making it available! I think 65uino Mega is a good name for a future version which adds more memory, a full 6502 maybe some ADCs… ;) and a cartridge slot…
Anders Nielsen  3:06 PM
The waste stream I refer to is slightly abstract. Millions of Atari 2600's have already been recycled and I have a feeling there's still piles of boards in a container somewhere. If we buy those from the usual markets, we encourage the scrappers to save the chips instead of just melting them down.
Anders Nielsen  3:06 PM
@Andy Geppert Someone on Twit.. I mean X.. Suggested a 68Kuino :D
Andy Geppert  3:07 PM
Oh, and thanks for making the bootloader and dev work flow to go with it!
Andy Geppert  3:07 PM
Oh yes, 68Kuino needs to be done too!
Dan Maloney  3:08 PM
One vote for the 1802uino too. Probably the only one :-(
Eric Hertz  3:08 PM
What language do you most-use for 6502 programming?
jdanen  3:09 PM
@Eric Hertz - cool site, but there's an ocean in the way, shipping might get expensive :p @Anders Nielsen - ah, so basically picking the chips out by the invisible hand of the market, not a half bad idea
Anders Nielsen  3:09 PM
I try to explain most pieces of tech and code I use in my videos - but lemme tell you.. Editing video of 6502 assembly code and making it interesting is tough.
Anders Nielsen  3:10 PM
@Eric Hertz I'm slightly interested in that "phone" too :D
Anders Nielsen  3:10 PM
I mostly just go with 6502 assembly - cc65 does a decent job with C i head, but I haven't played with it much.
Jacob Christ  3:11 PM
It so easy to assemble by hand, why do you even use an assembler?
Eric Hertz  3:12 PM
LOL use toggle switches!
Mitsuru Yamada  3:12 PM
In my case, it is my homebrew floating point interpreter (7kB) or hand assembly.
Anders Nielsen  3:12 PM
@Jacob - almost getting there :) Actually want to build one like @Mitsuru's - but RAM only :D I have something to show you @Dan Maloney ...
Andy Geppert  3:13 PM
@Jacob Christ LOL. Reminds me of graph paper and a mechanical pencil to organize the bytes.. Ah, memories. I’m anxious to get back into 6502 assembly.
Jacob Christ  3:14 PM
@Mitsuru Yamada Nice builds!
Mitsuru Yamada  3:14 PM
I think 6502 is suitable for easy to creating machine language programs because of its small number of instructions.
Xark  3:14 PM
llvm-mos is an interesting C/C++ (and even Rust) compiler for 6602 also, but 6502 is a bit "resistant" to higher level code. 🙂 https://github.com/llvm-mos/llvm-mos-sdk
Anders Nielsen  3:15 PM
Mitsuru Yamada  3:16 PM
I used to run a C compiler on APPLE2, but I had to change floppies many times to compile it.
Anders Nielsen  3:16 PM
@Dan Maloney I'm not sure if I'll get to it before or after or in parallel with the 8051 - but I'm getting there
Dan Maloney  3:16 PM
:heart emoji:
Dan Maloney  3:18 PM
I'd honestly love to build a replica of the COSMAC VIP I had way back when. No idea where it went. Must have cost my parents a fortune
DrG  3:18 PM
Anders / Mitsura - do either of you have any stories or experiences with the 6501 [six five zero one]?
Anders Nielsen  3:18 PM
Oh how I wish I had an Apple II to be frustrated with floppies about
Anders Nielsen  3:19 PM
@DrG As far as I know it barely existed. MOS created it as a gimmick to show it could be done cheaper but everyone was supposed to want the 6502 for the builtin oscillator driver
Anders Nielsen  3:20 PM
You'll notice the programming manual is actually called the MSC6500 Family Programming manual
Xark  3:20 PM
I read it never actually shipped.
Xark  3:21 PM
6507! 😅
Anders Nielsen  3:21 PM
From what I've head they did bring it to WESCON but after that, not so much.
CJ Keithley  3:21 PM
I quite enjoyed the Rockwell R6501Q… quip (quad in-line package)
Anders Nielsen  3:22 PM
I wish the 6504 was easier to get my hands on. It should also be compatible with the #65uino if you have one of those.
CJ Keithley  3:23 PM
Rockwell also made a 68000 quip… they must have sold hundreds of those! :-)
Xark  3:23 PM
6501Q....cool, I have not heard of those before.
Mitsuru Yamada  3:24 PM
In my experiments, the built-in oscillator did not have a good duty cycle.
Pete Willard  3:24 PM
Quad Inline is such an odd bird... and kind of a nightmare
CJ Keithley  3:24 PM
The R6501Q had (in a single chip) a 6502 variant, (a little bit of) RAM, parallel IO, and a serial port.
Pete Willard  3:24 PM
MC6800 also has some weird clock requirements, for comparison.
Jacob Christ  3:26 PM
So when I was learning 6502 assembly on an Apple II there was program that let you visualize an assembly program running that ran on an Apple II. It would show data moving from memory into registers and the registers feeding the ALU and to the accumulator then back to memory again. It was a great visualization tool. I'm wondering if others have seen it, knows what its called and know if there is a web page based equivalent that exists?
CJ Keithley  3:26 PM
https://web.archive.org/web/20221102041722if_/http://archive.6502.org/datasheets/rockwell_r6501q.pdf
Anders Nielsen  3:26 PM
@Mitsuru Yamada Exactly. It's there but everyone is better off generating the clock elsewhere.
Andy Geppert  3:27 PM
@Anders Nielsen What tricks have stood out to you as you use 6502 assembly to do fast pulses/timing stuff? I know some of them are in your video about driving serially addressable LEDs. Curious where you bump into timing limitations between 6502 and the modern area, and what tricks you use to bridge to more modern ‘tronics.
Xark  3:27 PM
@Jacob Christ Perhaps https://www.youtube.com/watch?v=aZvss4XnceU ?
Anders Nielsen  3:27 PM
@Pete Willard The big difference was the 6800 required you to input both phase clocks yourself
DrG  3:28 PM
DrG  3:28 PM
My first computer - still have it and it still works (it is a rev b)
Pete Willard  3:28 PM
Yup, it did... and therefore... excess glue logic outside the CPU
Xark  3:28 PM
Nice!
Anders Nielsen  3:29 PM
@Andy Geppert I lean a lot on cool people like George Foot, Garth Wilson and good folks over at forum.6502.org
Andy Geppert  3:29 PM
@DrG That is SOOO on my shopping list.
Jacob Christ  3:29 PM
@Xark That's exactly the program!
Andy Geppert  3:30 PM
Oh, I recognize the Garth Wilson name - he has shared so many great resources.
Pete Willard  3:30 PM
Cool. Mine was an MEK6800... Still have it.
Anders Nielsen  3:30 PM
Timing can usually be fixed with a 74'74 and a gate if it's that bad - usually I try to avoid the edge cases. Driving ws2812's was one of those XD
Anders Nielsen  3:30 PM
@DrG Wow. Hang on to that one!
Mitsuru Yamada  3:32 PM
As for the difficulty with the 6800 clock, I solved it with the 6802, which can generate a stable clock using only an external crystal.
Andy Geppert  3:33 PM
I recently learned of, and purchased, and EMMA II which is a 6502 microprocessor trainer. Very similar to the KIM, but not a KIM. Anyone else here know about the EMMA II or have experience with one? I’m a 6502 enthusiast and I was surprised to learn about it recently. Apparently more popular in Europe, and I’m in the US.
Anders Nielsen  3:34 PM
@Mitsuru Yamada I see it was released in '76.. Wasn't that the reason MOS counter sued Motorola? :D
Pete Willard  3:35 PM
While the 6802 got a lot of things right, it still could not touch a 6502 in terms of price...
Xark  3:35 PM
I never heard of EMMA II, but pic from 6502.org (looks pretty nice). http://forum.6502.org/download/file.php?id=288&sid=30b5fe24dca784d18184aa56102bde21&mode=view
Anders Nielsen  3:36 PM
@Andy Geppert Hans Otten to the rescue: http://retro.hansotten.nl/6502-sbc/emma-by-l-j-technical-systems/
Andy Geppert  3:36 PM
It was sold with several mechatronic accessories and training manuals, originally, intended for tech/trade school use. From my understanding.
Anders Nielsen  3:36 PM
@Andy Geppert So someone made a remake?
Andy Geppert  3:37 PM
No, it’s an original. I purchased at a VCF. Costed much less than a KIM!
DrG  3:37 PM
DrG  3:37 PM
+1 on the importance of 6502 price.
Andy Geppert  3:38 PM
Thanks for the Hans link.
Anders Nielsen  3:38 PM
We have way too few VCF's in Denmark :D
Andy Geppert  3:41 PM
Well, VCF is growing in the US right now and there are some people that would happy to help enable growth in Denmark with their experience! VCF does an amazing job of filling the niche.

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