17:27 Actually, quite a lot of processors were like this. I think the Z80 did the same. And IBM POWER/PowerPC (as used for a while in Apple Macs, and still in a few servers and supercomputers being sold to this day) similarly had no predefined hardware stack: the “stack” was purely a convention of the software ABI, and the hardware interrupt handling didn’t require any stack.
15:21 That sounds like enough room for 4 screenfuls. Do you set a hardware register to specify which screenful to display? And do quick switching between displays that way?
@@stephenwalters9891 True, but there may be replacements. Or you could hook it up to a serial terminal or terminal emulation. THat's super simple for an 1802. You don't need to add a UART to the computer. The only additional hardware would be a relatively cheap MAX232 to do the level shifting to RS232 levels on the serial I/O lines. It would be the processor that emulated a UART in software. I have one on a breadboard. Just 6 ICs, the processor, 32k ROM, 32k RAM, the MAX232 and two 74HCXXX logic ICs. Not complicated or expensive at all. The simplest 1802 based computer possible if you overlook the need for a serial terminal.
@@stephenwalters9891 You really would not need a FPGA for that. These ICs all worked in a similar way, working closely together with the processor's interrupt and DMA features. Look up Lee Hart's VIP 2000. It generated similar graphics with an EPROM and some logic ICs. In a higher resolution and allowing the processor a little higher clock frequency. But, like all these solutions, this stole quite a fe bus cycles from the processor with all these DMA and interrupt cycles. That's also the reason why the computer in this video appears to be so slow. The processor could easily be twice as fast without this kind of graphics. But for 1976 it was the simplest and cheapest solution to have graphics at all.
@@AlsGeekLab Actually - the principal purpose of the lens is not to embiggen the display, but to focus it (Emfocussen?) - the wall is too close to the projector :)
Interesting, and a nice example of an attempt at gaslighting in the title. It was very far from the first microcomputer in New Zealand. The universities and polytechs were already teaching design based on the more popular and better supported 8080 and 6800 systems. Auckland University introduced students to their 8085 boards in Q3 of 1976. By 1977, there was widespread design and construction of such Motorola and Intel systems across New Zealand dating from at least 2 years earlier due to the high import duties prevailing at the time for assembled boards and systems. Magazines of the time (QST, 73, NZ's Break-In ham journal, etc) all describe these efforts clearly. The 1802 was an odd out-of-step late and largely ignored entry into the vibrant microprocessor development community with the sole useful feature of low current drain. That was largely obviated by the high current peripherals and support devices needed in a working system.
The 1802 was available in 1974 and could be purchased from an RCA dealer for $20 (mid 70s money granted) and had onboard I/O similar to what an Arduino offers today. Anything from Intel would have been five times that and needed additional support chips. Other than being CMOS which allowed for a single 5V supply and no minimum clock frequency, the instruction set was very friendly for beginners.
And here we are 40 years later and we are still repeating the same old songs. Yes, it was not derived from anything made by Intel. You and your magazines call that odd. In reality these were more like ideas that were not appreciated and undersupported at that time yet. An early RISC architecture, CMOS architecture. You can even take the modern instructions on how to overclock a modern processor and apply them to the ancient 1802. In many ways the 1802 was more a preview of the things to come than any of the other 8 bit processors at the time. I always wondered how much inspiration the designers of the the most popular processors of all, the ARM processors, took from the 'odd' 1802.
I would LOVE to get one of these computers to put on display at the VCF Shows. That way, everyone can get to see it in person!
Love this story. Did hear about these but never got to see one
His memory of technical details is very good!
I thought so! Especially for the information he worked on was approx 45 years old!
17:27 Actually, quite a lot of processors were like this. I think the Z80 did the same. And IBM POWER/PowerPC (as used for a while in Apple Macs, and still in a few servers and supercomputers being sold to this day) similarly had no predefined hardware stack: the “stack” was purely a convention of the software ABI, and the hardware interrupt handling didn’t require any stack.
15:21 That sounds like enough room for 4 screenfuls. Do you set a hardware register to specify which screenful to display? And do quick switching between displays that way?
Very cool, I wonder if the schematics and ROMs are available as I have a 1802 chip sitting around waiting for a project.
There are no more CDP1864's !
@@stephenwalters9891 True, but there may be replacements. Or you could hook it up to a serial terminal or terminal emulation. THat's super simple for an 1802. You don't need to add a UART to the computer. The only additional hardware would be a relatively cheap MAX232 to do the level shifting to RS232 levels on the serial I/O lines. It would be the processor that emulated a UART in software. I have one on a breadboard. Just 6 ICs, the processor, 32k ROM, 32k RAM, the MAX232 and two 74HCXXX logic ICs. Not complicated or expensive at all. The simplest 1802 based computer possible if you overlook the need for a serial terminal.
@@CDP1861 There was a guy in the USA making a tiny board with fpga etc on it, but he's gone now.
@@stephenwalters9891 You really would not need a FPGA for that. These ICs all worked in a similar way, working closely together with the processor's interrupt and DMA features. Look up Lee Hart's VIP 2000. It generated similar graphics with an EPROM and some logic ICs. In a higher resolution and allowing the processor a little higher clock frequency. But, like all these solutions, this stole quite a fe bus cycles from the processor with all these DMA and interrupt cycles. That's also the reason why the computer in this video appears to be so slow. The processor could easily be twice as fast without this kind of graphics. But for 1976 it was the simplest and cheapest solution to have graphics at all.
23:02 Was there also an issue with patents over the PAL delay line?
This is hardcore.... projection using a makeshift screen :)
He also has a magnifying glass to big the display bigger!
@@AlsGeekLab Actually - the principal purpose of the lens is not to embiggen the display, but to focus it (Emfocussen?) - the wall is too close to the projector :)
@@hughanderson6801 I admire your work !
You got featured on Hackaday, by the way 😀
Interesting, and a nice example of an attempt at gaslighting in the title. It was very far from the first microcomputer in New Zealand. The universities and polytechs were already teaching design based on the more popular and better supported 8080 and 6800 systems. Auckland University introduced students to their 8085 boards in Q3 of 1976. By 1977, there was widespread design and construction of such Motorola and Intel systems across New Zealand dating from at least 2 years earlier due to the high import duties prevailing at the time for assembled boards and systems. Magazines of the time (QST, 73, NZ's Break-In ham journal, etc) all describe these efforts clearly. The 1802 was an odd out-of-step late and largely ignored entry into the vibrant microprocessor development community with the sole useful feature of low current drain. That was largely obviated by the high current peripherals and support devices needed in a working system.
The 1802 was available in 1974 and could be purchased from an RCA dealer for $20 (mid 70s money granted) and had onboard I/O similar to what an Arduino offers today. Anything from Intel would have been five times that and needed additional support chips. Other than being CMOS which allowed for a single 5V supply and no minimum clock frequency, the instruction set was very friendly for beginners.
The 1802 was available from 1976 @@senorverde09
A bit of click bate at best!:) I don't see any psychological manipulation taking place here!
And here we are 40 years later and we are still repeating the same old songs. Yes, it was not derived from anything made by Intel. You and your magazines call that odd. In reality these were more like ideas that were not appreciated and undersupported at that time yet. An early RISC architecture, CMOS architecture. You can even take the modern instructions on how to overclock a modern processor and apply them to the ancient 1802. In many ways the 1802 was more a preview of the things to come than any of the other 8 bit processors at the time. I always wondered how much inspiration the designers of the the most popular processors of all, the ARM processors, took from the 'odd' 1802.