"Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Arc/RPCs, peripherals, RISCOS operating system & ARM kit eg GP2x, BeagleBoard
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Wed Mar 06, 2019 8:47 pm

IanS wrote:
Wed Mar 06, 2019 8:12 pm
Impressive.
How much of the OS have you had to include/re-implement to do the text display?
Thanks!

A reasonable amount of the low level stuff... initializing MEMC and VIDC took a while to get right, as did keyboard IO. Once I had it starting up and clearing the screen, plotting text was just a matter of decoding the bytes from the RISC OS system font and writing them to the appropriate place in screen memory. Took me a while because I haven't written that much ARM assembly. Luckily the gnu-arm-embedded / arm-eabi-none-gcc toolchain seems to generate ARMv2 code just fine, so I could write most of it in C/C++ -- things sped up a lot at that point. There's no heap, so malloc() etc won't work, but that hasn't been an impediment so far. Here's most of the code:

- Low level startup (assembly) - mem size detection, MEMC and VIDC init, banner printer. The intention here is to also provide a basic POST, so nothing in this file should depend on working RAM; it only uses registers for storage.
- Main menu code
- IOC registers
- Text display code and font from RISC OS source
- Keyboard IO routines

Plus some open source bits:
- nanopb, which lets me use the protobuf format for OS/CMOS/menu metadata.
- Some C library routines (divmod, memcpy, memset) from arm-trusted-firmware.
- stb_sprintf for string formatting

I just realized that most of this probably won't work on a Risc PC... not looking forward to getting it all working there! I wonder if I can steal more of the RISC OS startup code and do a less "bare metal" version there, given that the open source version will build and run on IOMD machines.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sun Mar 10, 2019 8:09 am

Risc PC update: I’ve managed to strip out pretty much everything from the ROOL RISC OS 5.27 source except for the HAL and kernel, plus keyboard and mouse drivers, which gives a rom image slightly below the 500kB mark, and boots to the supervisor prompt in RPCemu. This should be a nice base to get the Arcflash bootloader working there!
Last edited by myelin on Sun Mar 10, 2019 8:09 am, edited 1 time in total.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by danielj » Sun Mar 10, 2019 8:28 am

Haha! Awesome! What are you using to compile? gcc again?

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sun Mar 10, 2019 11:31 am

danielj wrote:
Sun Mar 10, 2019 8:28 am
Haha! Awesome! What are you using to compile? gcc again?
Haha... that would be a bit ambitious :) Just using the standard RO build environment and the ROOL DDE for this! Fitting my GCC built Arc bootloader together with the DDE built RPC one is going to be interesting...
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sun Mar 10, 2019 6:48 pm

Actually on second thoughts it looks like it won’t be too hard. I found the FileSwitch FSControl Run source and all it does is copy the app to &8000, call a SWI to flush the StrongARM cache, and jump to the exec address. I thought I’d have to get something to map RAM in there, but I guess the OS does that on startup.

As such I’ll just get the Kernel boot process (NewReset) to jump to my code once it’s done, and I’ll do the copy and run from there — and I should be able to use the same build system (GCC etc) as for the Arc bootloader.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Tue Apr 16, 2019 5:48 am

I haven’t posted in here for a bit... here’s a status update:

- The Risc PC bootloader is working under emulation; I’m yet to test it on actual hardware.
- The dual platform bootloader works great; one rom image for both Archimedes and RPC.
- I’ve acquired an A310 and verified that the Arcflash hardware works fine there.

... and the first test board is about to leave my hands; IanS is going to try it out on his “difficult” A3000. If it works there, I think I’ll feel confident doing a small production run for people with A3xx/4xx/A3000 machines :)
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by stevebubs » Sat Apr 20, 2019 12:25 pm

Is it too late to declare an interest in both a 4 ROM version, and a RPC version?

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sat Apr 20, 2019 3:06 pm

stevebubs wrote:
Sat Apr 20, 2019 12:25 pm
Is it too late to declare an interest in both a 4 ROM version, and a RPC version?
Not at all! I’ve only just sent out the first board for testing, so there’s plenty of time before I do the first run, even. That’ll be a small run of 8-9 boards, which will go to folks who are either very hardware/software minded or use their Archimedes machines a lot (I’ll send out a questionnaire nearer that time)... then once they’ve had a go at it and I’ve made the software work a little more smoothly, I’ll do a bigger run and everyone can get their boards :)
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by paulv » Sat Apr 20, 2019 3:17 pm

I really need to get my ar*e into gear and get my A410/1 dev machine up and running so I can look at building a ROM compatible version of AutoVIDC so it can go into a 3.2x ROM Image at the moment it uses too much of the original codebase I inherited with self modifying code instead of allocating some working memory for what it needs to do.

Paul

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Thu Apr 25, 2019 8:28 pm

Well... I should have done this test earlier:
2019-04-25 Risc PC rom separation.JPG
I just tried plugging in an Arcflash board with Risc PC adapter, only to find that I'm about 0.05" off. Looks like the Risc PC ROM sockets are about 0.25" apart (c.f. 0.1" for A5000, 0.2" for all other 4-ROM machines).
Last edited by myelin on Thu Apr 25, 2019 8:29 pm, edited 1 time in total.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by Kazzie » Fri Apr 26, 2019 12:10 pm

I've been reading the thread quietly thus far, mainly because my A420/1 wasn't really up and running yet.

Now that it is, I'd like to mention my interest in a board, and also willingness to help with testing where I can.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by stevebubs » Fri Apr 26, 2019 7:09 pm

myelin wrote:
Thu Apr 25, 2019 8:28 pm
Well... I should have done this test earlier:

2019-04-25 Risc PC rom separation.JPG

I just tried plugging in an Arcflash board with Risc PC adapter, only to find that I'm about 0.05" off. Looks like the Risc PC ROM sockets are about 0.25" apart (c.f. 0.1" for A5000, 0.2" for all other 4-ROM machines).
Are there any other motherboards you'd like checked? I've started going through and refurbing my machines so can check as I go...

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Fri Apr 26, 2019 7:54 pm

stevebubs wrote:
Fri Apr 26, 2019 7:09 pm
Are there any other motherboards you'd like checked? I've started going through and refurbing my machines so can check as I go...
Yes please! So far I've personally checked A3000 (0.2" separation), A310 (0.2"), A5000 (0.1"), and RPC600 (0.25"), and IanS has checked A540 (0.2"). Remaining to verify for sure:

- A4xx/1 (probably 0.2" like A3000/A310/A540?)
- A3010 (maybe 0.25" like RPC600?)
- A3020 (maybe 0.25" like RPC600?)
- A4000 (maybe 0.25" like RPC600?)

I'd be surprised if the A4xx/1 is any different to the other three-digit machines, but given that there were never carrier boards for the A3010/3020/4000, they could be all over the place :)
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by daveejhitchins » Fri Apr 26, 2019 8:06 pm

You need a rule with 1/10ths of an inch scale - a 6" and 12" - still available in this country, but hard to find. Should be readily available in the US?

Nearly all PCBs BITD were laid out on a 0.1" grid (thank goodness) - So it easy to measure where everything is. The AP6 is a case in point I had to line-up with 4 x ICs on the Plus 1 motherboard.

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by stevebubs » Fri Apr 26, 2019 8:08 pm

myelin wrote:
Fri Apr 26, 2019 7:54 pm
stevebubs wrote:
Fri Apr 26, 2019 7:09 pm
Are there any other motherboards you'd like checked? I've started going through and refurbing my machines so can check as I go...
Yes please! So far I've personally checked A3000 (0.2" separation), A310 (0.2"), A5000 (0.1"), and RPC600 (0.25"), and IanS has checked A540 (0.2"). Remaining to verify for sure:

- A4xx/1 (probably 0.2" like A3000/A310/A540?)
- A3010 (maybe 0.25" like RPC600?)
- A3020 (maybe 0.25" like RPC600?)
- A4000 (maybe 0.25" like RPC600?)

I'd be surprised if the A4xx/1 is any different to the other three-digit machines, but given that there were never carrier boards for the A3010/3020/4000, they could be all over the place :)
OK.. I can do all the above except 3020.. Bear with me..

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Fri Apr 26, 2019 8:10 pm

daveejhitchins wrote:
Fri Apr 26, 2019 8:06 pm
You need a rule with 1/10ths of an inch scale - a 6" and 12" - still available in this country, but hard to find. Should be readily available in the US?
Very readily available in the US! So much so that it's hard to find things denominated in sensible units like millimetres here :)

A good trick is to use a strip of 0.1" pin header (as seen in all IanS's posts on the first page of this thread), or a DIP ROM chip (pictured above), all of which have 0.1" pin spacing.
stevebubs wrote:
Fri Apr 26, 2019 8:08 pm
OK.. I can do all the above except 3020.. Bear with me..
Excellent! No hurry... I'm going to do a respin of the Risc PC adapter board next time I send something off (which will hopefully be a big order including Arcflash v1 and the Elk ULA FPGA board), but that won't be for a few weeks at least.
Last edited by myelin on Fri Apr 26, 2019 8:12 pm, edited 1 time in total.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sat Apr 27, 2019 6:06 am

This might just work to let me try out a Risc PC... if I solder the pins in on an angle, then bend the ends back slightly, I think I can get them in, maybe using a second socket to align them all.
1FD47AC2-9F8F-43B4-ACB7-53D97B731FB6.jpeg
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sat Apr 27, 2019 10:10 pm

Success! It works on my RPC600, although the communication channel that uses the last 16 bytes of the ROM area is causing ROM checksums to fail. RISC OS 4.02 boots fine, and when I replace the StrongARM-233 card with an ARM610 card, RISC OS 3.60 and 3.71 also work.

I didn't have any luck with the bootloader, and something I did managed to make the Risc PC attempt to power itself from the USB supply, which is a bit concerning (I may have to abandon the ability to power the board over USB, for safety), so there's obviously a bit more work to do, but I'm glad to see that the basic function of providing ROM images is working.

Update: I thought I'd fried my Risc PC there after it didn't come back to life when I removed the Arcflash board and put the RO402 ROMs back in... except an hour later I took another look and realized I'd put the chips in BACKWARDS. Flipping them around, my machine worked fine again. Phew!
Last edited by myelin on Sat Apr 27, 2019 11:32 pm, edited 1 time in total.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by IanS » Sat Apr 27, 2019 10:36 pm

myelin wrote:
Sat Apr 27, 2019 10:10 pm
Success! It works on my RPC600
Excellent news.

I can confirm that the board you sent me also works fine on my A3000.
IMG_20190427_200235_HDR.jpg
Bootloader Menu
IMG_20190427_201337_HDR.jpg
RISC 3.20

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sat Apr 27, 2019 11:34 pm

IanS wrote:
Sat Apr 27, 2019 10:36 pm
I can confirm that the board you sent me also works fine on my A3000.
Very cool! Is this the "difficult" A3000 that was causing all sorts of trouble with the early versions of Chris Morley's 4MB RAM cards? If it passes muster in that one, I think it's probably safe to say it works :)

Time for me to put the finishing touches on the v2 PCB design and get some more test units made...
Last edited by myelin on Sat Apr 27, 2019 11:44 pm, edited 1 time in total.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by IanS » Sun Apr 28, 2019 11:09 am

myelin wrote:
Sat Apr 27, 2019 11:34 pm
Very cool! Is this the "difficult" A3000 that was causing all sorts of trouble with the early versions of Chris Morley's 4MB RAM cards? If it passes muster in that one, I think it's probably safe to say it works :)
I think my A3000 has unfairly got a bad reputation. It may be marginally worse than others, but most (if not all) issues I saw with the RAM card were also seen by Chris on his A3000.

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by stevebubs » Sat May 11, 2019 12:52 pm

myelin wrote:
Fri Apr 26, 2019 8:10 pm
stevebubs wrote:
Fri Apr 26, 2019 8:08 pm
OK.. I can do all the above except 3020.. Bear with me..
Excellent! No hurry... I'm going to do a respin of the Risc PC adapter board next time I send something off (which will hopefully be a big order including Arcflash v1 and the Elk ULA FPGA board), but that won't be for a few weeks at least.
A3010.. A shade under 0.4"
20190503_214520.jpg
Last edited by stevebubs on Sat May 11, 2019 12:53 pm, edited 1 time in total.

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by IanS » Sat May 11, 2019 1:16 pm

stevebubs wrote:
Sat May 11, 2019 12:52 pm
A3010.. A shade under 0.4"
Measuring the pins on the other side is probably more accurate, but based on the vectorlight IDE board, they look to be exactly 0.4"
https://www.vectorlight.net/retro/compu ... dification

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by Joka80 » Sat May 11, 2019 7:23 pm

IanS wrote:
Sat Apr 27, 2019 10:36 pm
myelin wrote:
Sat Apr 27, 2019 10:10 pm
Success! It works on my RPC600
Excellent news.

I can confirm that the board you sent me also works fine on my A3000.

IMG_20190427_200235_HDR.jpg
IMG_20190427_201337_HDR.jpg
IanS, was RISC OS 3.20 available for the A3000? Thought it’s max operating system was 3.11 or the German 3.19 equivalent?

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by IanS » Sat May 11, 2019 7:28 pm

Joka80 wrote:
Sat May 11, 2019 7:23 pm
IanS, was RISC OS 3.20 available for the A3000? Thought it’s max operating system was 3.11 or the German 3.19 equivalent?
3.20 is not an official acorn release. See here - viewtopic.php?t=14110#p186819

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by Joka80 » Sat May 11, 2019 7:45 pm

Yes...is this still in testing I take it and is it reliable? Is anybody going to to actually start producing this you think IanS?

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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Sat May 11, 2019 8:55 pm

Arcflash is definitely happening; I have what I think is the final PCB design for v2, so I just need to finish the PCB for the Electron ULA (see the Ultimate Upgrade thread in the 8 bit section for more) and then I’ll send them both off and build some of each. Expect the first batch of v2 boards (for all the four ROM machines except A5000) to ship within a couple of months. Then it’s beta test time, and if that goes well I’ll make more.

RO3.2 is a bit further away. I believe it needs volunteer programmers; sirbod has built a rom that boots, and has a laundry list of things that need doing.
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Re: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?

Post by myelin » Tue Aug 13, 2019 4:33 am

Well... just goes to show that you can't trust any of my estimates :lol:

I just soldered up the first three Arcflash v2 boards and am in the process of programming and testing them.
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