Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by northernbob » Wed Feb 27, 2019 7:34 am

possible route to a faster connection...

https://www.facebook.com/notes/s80-stac ... _tn__=HH-R

lifi link between beeb and pi.?

the s80 project is worth watching imo.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by iainjh » Sat Mar 09, 2019 11:27 pm

Hi, i have a Model B & the pi co pro. Works great. BBC is modded to take a 64k eeprom image.

I had been successfully using Beebaid's *tubeoff or tab/break to disable the co-pro before running games. Until recently i blew a new 64k eeprom (still containing beebaid), and now beebaid no longer works! Only *fx 151,230,14 works for me right now and its a bit longwinded. I've moved its location...no luck.

I've build seemingly dozens of new 64k rom images and no joy. Beebaid still runs, but states 'the tube is already off' and no longer toggles the tube.

Can someone please suggest an alternative rom that has a working *tubeoff /*tubeon , or, maybe, tell me why beebaid is no longer working for me?

tia

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BeebMaster » Mon Mar 11, 2019 5:29 pm

Maybe the order of the ROMs is important to BeebAid? Could it be that it needs to be lower or higher than the ROM with Tube host code (DNFS/1770 DFS)? Perhaps making a 64K ROM has altered the order of the ROMs.
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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BeebMaster » Mon Mar 11, 2019 5:47 pm

Could we have a configurable, or higher default, RAM allocation for the Native ARM co-pro? 64MB would be great, and the reason I say that is it would allow an entire real-life Winchester disc to be read into RAM all in one go (there can't be many Winnies bigger than 60MB out there) then a quick fiddle with what you've got dangling from your 1MHz and you could change from your source Winnie to your destination grain of silicon and continue with the backup.
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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by hoglet » Mon Mar 11, 2019 6:01 pm

BeebMaster wrote:
Mon Mar 11, 2019 5:47 pm
Could we have a configurable, or higher default, RAM allocation for the Native ARM co-pro? 64MB would be great, and the reason I say that is it would allow an entire real-life Winchester disc to be read into RAM all in one go (there can't be many Winnies bigger than 60MB out there) then a quick fiddle with what you've got dangling from your 1MHz and you could change from your source Winnie to your destination grain of silicon and continue with the backup.
What is it at the moment? 16MB? Unfortunately, It's not quite as easy as changing a number somewhere.

Increasing to 30MB would be easy I think, more than that requires changing quite a few other things.

Currently the PiTubeDirect kernel loads to 0x01F00000 (31MB in the memory map) and the various stacks sit just below this.

The memory the Co Pro's see starts at 0x00000000.

So whilst there is 512MB of RAM, it's kind of hard to use at the moment.

Dave
Last edited by hoglet on Mon Mar 11, 2019 6:15 pm, edited 1 time in total.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Mon Mar 11, 2019 6:45 pm

It has been on my list to re organise the ram to enable larger memory , but with no actual requirement till now it has been at the bottom of my todo list.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by hoglet » Mon Mar 11, 2019 6:55 pm

dp11 wrote:
Mon Mar 11, 2019 6:45 pm
It has been on my list to re organise the ram to enable larger memory , but with no actual requirement till now it has been at the bottom of my todo list.
Any thoughts on how to deal with the 256MB vs 512MB possible RAM on the Pi One?

i.e. Drop the older 256MB models, or separate 256MB and 512MB build?

All Pies are listed here:
https://elinux.org/RPi_HardwareHistory

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Last edited by hoglet on Mon Mar 11, 2019 6:57 pm, edited 1 time in total.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Mon Mar 11, 2019 7:24 pm

I was thinking of dropping pi 1 , but we could say limit copros to 240Mbytes . I don't really want another build.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by RobC » Mon Mar 11, 2019 7:57 pm

GoSDC will allow you to backup a real Winchester and write a new image to it.

As far as I know, it'll handle the maximum size under ADFS (512MB).

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by scruss » Tue Mar 12, 2019 12:16 am

hoglet wrote:
Mon Mar 11, 2019 6:55 pm
dp11 wrote:
Mon Mar 11, 2019 6:45 pm
It has been on my list to re organise the ram to enable larger memory , but with no actual requirement till now it has been at the bottom of my todo list.
Any thoughts on how to deal with the 256MB vs 512MB possible RAM on the Pi One?
TBH, the 256 MB ones are so rare (and almost all use the old 26-pin header format) that it would be reasonable to drop support for them.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by strawberrytau » Mon Apr 01, 2019 1:51 pm

iainjh wrote:
Sat Mar 09, 2019 11:27 pm
Hi, i have a Model B & the pi co pro. Works great. BBC is modded to take a 64k eeprom image.

I had been successfully using Beebaid's *tubeoff or tab/break to disable the co-pro before running games. Until recently i blew a new 64k eeprom (still containing beebaid), and now beebaid no longer works! Only *fx 151,230,14 works for me right now and its a bit longwinded. I've moved its location...no luck.

I've build seemingly dozens of new 64k rom images and no joy. Beebaid still runs, but states 'the tube is already off' and no longer toggles the tube.

Can someone please suggest an alternative rom that has a working *tubeoff /*tubeon , or, maybe, tell me why beebaid is no longer working for me?

tia
Iain - did you manage to fix this? I am also struggling to get BEEBAID TUBEON/OFF working on my BBC B.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by jgharston » Mon Apr 01, 2019 2:08 pm

There's disk-based *TUBE ON|OFF|num on Tube Utilities Disk.

And the BBC ROM Manager & Utilities has a ROM-based *TUBE ON|OFF|num command.
Last edited by jgharston on Mon Apr 01, 2019 2:09 pm, edited 1 time in total.

Code: Select all

$ bbcbasic
PDP11 BBC BASIC IV Version 0.25
(C) Copyright J.G.Harston 1989,2005-2015
>_

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by strawberrytau » Mon Apr 01, 2019 2:48 pm

jgharston wrote:
Mon Apr 01, 2019 2:08 pm
There's disk-based *TUBE ON|OFF|num on Tube Utilities Disk.

And the BBC ROM Manager & Utilities has a ROM-based *TUBE ON|OFF|num command.
Thanks Jonathan. That's very helpful!

Can you please point me in the right direction to find the ROM-based *TUBE on your site? I have intalled SRAMv130, but it doesn't seem to have this command. Have I got the correct ROM?
Screenshot 2019-04-01 at 15.45.17.png
Screenshot 2019-04-01 at 15.45.27.png
Screenshot 2019-04-01 at 15.45.34.png
Last edited by strawberrytau on Mon Apr 01, 2019 3:07 pm, edited 2 times in total.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by northernbob » Wed Apr 03, 2019 6:40 am

i spotted this recently....

the pi 4 has a built in z80! eg it comes with an fpga

https://youtu.be/Y1fcQb708vw

....yes and also a 6502.

(sadly this might all be fake)
Last edited by northernbob on Wed Apr 03, 2019 6:49 am, edited 2 times in total.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by hoglet » Wed Apr 03, 2019 6:43 am

northernbob wrote:
Wed Apr 03, 2019 6:40 am
i spotted this recently....

the pi 4 has a built in z80! eg it comes with an fpga
You are two days late - April 1st was on Monday.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Mon Jun 24, 2019 6:05 am

PiTubeDirect now supports the new Raspberry Pi4 (see :https://www.raspberrypi.org/products/ra ... 4-model-b/)

My work so far should be considered as beta. Cores programmed in C see a good performance increase . Arm native core is now so fast some work is needed on the CLOCKSP program as I get divide by zero errors!

There is still a few jobs to sort out e.g LED isn't driven. I've moved over to the latest version of GCC ( https://developer.arm.com/tools-and-sof ... /downloads) so you will need that installed and on your path under linux ( windows WSL is what I use) if you want to rebuild. Git hub should be updated later on today.

To use the the code you will need the in addition to the files in github the following files from Raspberry Pi 4 SDCARD : start4cd.elf fixup4cd.dat bcm2711-rpi-4-b.dtb

If you want a new Raspberry Pi quickly and in or around Cambridge then the shop in the Grand arcade has stock.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by Elminster » Mon Jun 24, 2019 10:58 am

I was going to ask if anyone could think of a project where the extra abilities of the Pi4 will help.

Not ordered one yet, with 16 of them already I really need to think of a reason (excuse) to get another one.

Not sure the updated code is a reason but at least I know I can use it as a co-pro

=D>

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by fordp » Mon Jun 24, 2019 8:17 pm

Amazing work the fastest second processor in the world just got a bit faster!
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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Sun Aug 11, 2019 12:55 pm

I've had a few spare minutes and done a bit more work on the Pi4. On the dom_tmp_1 branch I've improved the the 6502 performance for the RPi4.

RPi3B+ (1.4GHz)
armcode 6502 : 339MHz
lib6502 : 131.56MHz
Z80 86.78MHz
ARM 151.46MHz
nativeARM : 20,735MHz

RPi4 ( 1.5GHz)
armcode 6502 : 370MHz
lib6502 : 237MHz
Z80 126MHz
ARM 246MHz
nativeARM : so fast it breaks clocksp

As you can see cores coded C have some really good performance gains.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BigEd » Sun Aug 11, 2019 5:32 pm

A very fast Z80! And perhaps a fast ns32k too? (In that case, especially, not highly-tuned C code, but a free speedup is always welcome.)

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by Elminster » Sun Aug 11, 2019 5:54 pm

Is the rpi4 still being powered from the Beeb? I not got around to getting a rpi4 yet so not sure on real world draw. I am guessing it probably draws (in use with nothing else hanging from it) around 1amp.

My rpi3+ cluster with 4 zeros only draws about 1.5 amps when running all cores around max.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Sun Aug 11, 2019 8:19 pm

I'm currently using my Pi4 Powered off my master, but the master doesn't have much load. Looking around the internet I see some people are over clocking the Pi4 to 2GHz others get a lees of a boost. Might be worth a try if you want even more performance.
Last edited by dp11 on Sun Aug 11, 2019 8:20 pm, edited 1 time in total.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by Elminster » Sun Aug 11, 2019 8:47 pm

Pi does tend to overheat, and throttle back. A heat sink should sort that but overclocking may need a small fan, which would increase load even more.

My Master has a meanmell so puts out twice the amps of a normal master; but just wondering if a Pi4 might be getting near the limit, especially if other stuff hanging off it, of the average save Beeb B.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BigEd » Sun Aug 11, 2019 9:02 pm

Does the Pi - especially the Pi 4 - still do thermal throttling even when running PiTubeDirect's bare metal code?

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Sun Aug 11, 2019 9:10 pm

As only one core is used and video output is not used., I've not seen the temp go above 55c.

PiTubeDirect turns of throttling.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by jgharston » Sun Aug 11, 2019 9:42 pm

Unless I've missed it, any chance of the PDP-11 CoPro on the PiTube so I don't have to keep swapping between PiTube and Matchbox. :)

Code: Select all

$ bbcbasic
PDP11 BBC BASIC IV Version 0.25
(C) Copyright J.G.Harston 1989,2005-2015
>_

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by dp11 » Sun Aug 11, 2019 9:54 pm

*FX 151,230,11 is PDP-11 on PiTubeDirect

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by Elminster » Sun Aug 11, 2019 10:17 pm

dp11 wrote:
Sun Aug 11, 2019 9:10 pm
As only one core is used and video output is not used., I've not seen the temp go above 55c.

PiTubeDirect turns of throttling.
Ah okay, forgot only 1 core is used. Even with throttling on it wouldn't start till 80c I think it is.

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BigEd » Mon Aug 12, 2019 3:00 am

Great news - great news all round! (I'd meant to ask about powering the Pi from the host...)

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Re: Pi-based Co-Pro on the cheap - 100MHz 6502 for £10? (now 274MHz)

Post by BeebMaster » Wed Aug 14, 2019 6:35 pm

I'm having a bit of a problem with getting BASIC running on the ARM processors.

With the ARM Second processor, I can use AB without much trouble. It appears to load and execute at &1000.

However I can't load anything into the native ARM. I think I am meant to use BAS135, although I've also got BASIC 116 from somewhere (possibly extracted from a RISC OS machine). BAS135 appears to load at F000 and run at F12C. *RUNning it doesn't work, just get the flashing cursor forever. *LOAD doesn't appear to do the trick either because if I examine the RAM at F000 afterwards (or indeed using any other location I try) with ADT's *MEX, it just shows a page of zeroes.

However if I load it with the ARM second processor active, at F000, and then change to the native ARM, I can see BASIC 135 in RAM with *MEX, and *GO F12C runs it (although I tend to get a "not found" error, but then the BASIC prompt).

On any BREAK BASIC is lost and has to be reloaded or re GOed (GOne?!?)

Also PAGE (at &8F00) is lower than the load address of BASIC, so amn't I going to overwrite BASIC with BASIC at some point?!

Am I doing it wrong?
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