I had fun making it - and the video.

What do you guys think? (Warning: my 6502asm skills might be painful for some of you to watch)

https://youtu.be/NABU7gQDtcs

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New new new new new video out! Serial Bootloader for my 65uino
Also, check out: I2C on a 6502 Single Board Computer
and Complete hardware overview of my 6502 SBC R1

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

There’s still room for a trace or two but I’m very happy I’m not trying to make this by hand in 1978.

It’s hard to wait with the tape deck, but it’s also so hard to find time to play with homebrew DACs, resistor ladders, relaxation oscillators, comparators and so on.
Simple enough in my head though: 6502 -> DAC -> Tape -> Comparator -> 6502.
Any DACs that were around in 1978(introduced - actual part age doesn’t matter) that can still be sourced (cheaply)? R2R is fine but a dedicated era correct DAC would be cool and more general.
Either way - when I get around to making that video it will look amazing with reels spinning and all!

First I think I have to give a proper introduction to my board though - my friends and family are scratching their heads a lot when they see it…

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New new new new new video out! Serial Bootloader for my 65uino
Also, check out: I2C on a 6502 Single Board Computer
and Complete hardware overview of my 6502 SBC R1

I like this: if I understand correctly, these £2 modules give you serial-over-radio capability, which in your case you drive at the 6502 end with bit-banged SPI and at the other end with the SPI ports on a Pi.

I like the combination of
- low cost
- low complexity
- wireless
- not wifi

And a bootloader is an ideal program - it's all you need on your SBC!

The modules are basically a precursor to Bluetooth, which means they are very low power(like 7-15 mA. @ 3V) but reasonable bandwidth. 2Mbit in theory.
Not exactly serial over SPI. I basically implemented my own layer 2 - 2 bytes every packet for control data (like packet number) and 30 data bytes. Snappy enough that sending a 1k program is a blink.

I have a bunch things connected with these things so it’s fun that I can check my greenhouse temperature and stuff like that with a 6502..

I’m trying very hard to make sure everything I throw at my sbc is pretty cheap - I really should calculate BOM cost as it will definitely be a surprise to a lot of people how cheaply you can build a 6502 sbc with - use at your own risk - IC’s.

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New new new new new video out! Serial Bootloader for my 65uino
Also, check out: I2C on a 6502 Single Board Computer
and Complete hardware overview of my 6502 SBC R1

Ah - I see now, it's packetised over the RF. Interesting.

With an EEPROM shortage and a MAX3421 SPI to USB bridge shortage, your over-the-air binary transfer system could become become very popular.

I'm glad that you note the lack of security. Some people are completely oblivious and would deploy a similar system in a critical environment. Even for prototyping, a robust checksum would be very worthwhile to reduce accidental or malicious error. Over-the-air signed binaries would also be worthwhile, either for an individual unit or a class of hardware.

A general note for video presentation is the journalistic mantra "Tell 'em what you're going to tell 'em. Tell it to 'em. Then tell 'em what you've told 'em." This can be applied fractally and some people are quite able to hide facts like Cantor dust in a huge amount of useless padding. When used productively, it provides an index and a rationale. I distinctly don't follow journalistic practice when I'm writing. My style isn't for everyone but some people prefer a rant and ramble. It is also quite easy to skip around text. When watching most video presentations, it is painfully apparent that more structure is required.

1980s training videos are often good examples of structure because it was hard and expensive to make any production. Casual efforts existed but they had very little distribution. 3M had a well structured (and awfully styled) video about innovation. I think that I found it via the four hours of MIT OCW 15.356: How To Develop Breakthrough Products And Services.

If you have 56 minutes spare, I recommend Architecture of the CM-5, lecture by Daniel Hillis. Daniel Hillis very quickly establishes that the lecture will be a chronology and then draws minimal diagrams while describing the features and limitations of each iteration of massively parallel Connection Machine. At the end, you'll understand some of the quirks in CUDA. More importantly, you'll see that Danny Hillis is arguably following a 10 slide limit while using a chalk board for emphasis.

Richard Hamming's lecture about Hamming codes is more rambling but is also good because it explains rationale and development while giving career advice. Every other video on this topic is inferior; some entertainingly so. Regardless, it is directly relevant because it is the type of integrity check which reduces accidental or malicious error.

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Modules | Processors | Boards | Boxes | Beep, Beep! I'm a sheep!

I certainly couldn’t send this into the wild without noting that people can listen in with very little effort. It does however have a 16 bit CRC in hardware which makes it plenty reliable.
For security however, someone suggested RSA as it is probably easy enough to implement on the 6502 side - I might follow that..

And I will definitely take any and all advice on good presenting - must find the time to check out the lectures

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New new new new new video out! Serial Bootloader for my 65uino
Also, check out: I2C on a 6502 Single Board Computer
and Complete hardware overview of my 6502 SBC R1