Search found 1097 matches

by fordp
Tue Jan 12, 2016 7:42 pm
Forum: 8-bit acorn hardware
Topic: Matchbox ARM2 Co Processor
Replies: 67
Views: 6770

Re: Matchbox ARM2 Co Processor

hoglet wrote:
I've never heard of a C Compiler for the ARM Eval System. It would be cool to have one.

Dave
It is mentioned in one of the manuals. I will do some more digging!
by fordp
Tue Jan 12, 2016 5:58 pm
Forum: 8-bit acorn hardware
Topic: Matchbox ARM2 Co Processor
Replies: 67
Views: 6770

Re: Matchbox ARM2 Co Processor

I was just looking at HADFS on MDFS.

Would this be compatible enough to substitute for ADFS for an ARM or 32016 Second Processor?
by fordp
Tue Jan 12, 2016 5:50 pm
Forum: 8-bit acorn hardware
Topic: Matchbox ARM2 Co Processor
Replies: 67
Views: 6770

Re: Matchbox ARM2 Co Processor

I think all this original software came in ADFS format, so will be hard to use on MMC based systems. It would be nice to convert it to a set of .ssd images. Dave Well done Dave, awesome work yet again. In the short term conversion to DFS will allow some fun and games but long term too allow used of...
by fordp
Mon Jan 11, 2016 9:05 am
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

Do you happen to have the source for any pre-v1.02 ARM BASIC code? (I'm working from a disassembly at the moment, which is hard) Also, do you have binaries for any of the following versions? - BASIC V v1.02 - BASIC V v1.05 - BASIC V v1.09 I've updated bbcbasic/arm with all the ARM BASIC binaries I ...
by fordp
Sun Jan 10, 2016 6:21 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

OK, that was a bit of a noob mistake :lol: Turns out that the "bare metal" Pi 2 defaults to running at 600MHz, and to get it to run at 900MHz you need to add the following to config.txt: force_turbo=1 This disables the dynamic clock speed adjustment (which I guess is throttling down to 600MHz as it...
by fordp
Sun Jan 10, 2016 6:18 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

A few tweaks and now it looks faster than the real thing ;) IMG_20160110_172238.jpg Cool! I'm sure there's lots of scope for optimization here, as its written in C. Is this speed up from checking interrupts less frequently? Dave Not just that Dave, that is the majority however. Going to watch telly...
by fordp
Sun Jan 10, 2016 5:24 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

A few tweaks and now it looks faster than the real thing ;)
IMG_20160110_172238.jpg
by fordp
Sat Jan 09, 2016 6:18 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

Sorry for taking so long to come back but I was doing my other hobby and running 13.1 miles badly.

It comes up with an average of 29.04MHz.
by fordp
Sat Jan 09, 2016 2:05 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I would but both ARM Basic and 6502 Master Basic say "Bad Program" when I try and CHAIN or LOAD it!
by fordp
Sat Jan 09, 2016 1:00 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

If help on this is elsewhere sorry. I am a bit confused as to how to get the "AB" loaded. I can see the file in this collection: http://www.dunnington.info/public/BBC/ARMeval.html Two things puzzle me here. It claims the disks are a sort of ADFS format but they are not they are just zipped ???? The ...
by fordp
Sat Jan 09, 2016 10:30 am
Forum: 8-bit acorn hardware
Topic: Beeb FPGA
Replies: 513
Views: 55270

Re: Beeb FPGA

Hi Dave, I am just getting myself back on the hamster wheel after a break over Christmas. I notice you have updated MMFS, great stuff but the rom_image.bin has not been updated. Are the scripts to update the ROMs in Github, if not can you update the rom_image.bin. I am attempting to get the Pi ARM E...
by fordp
Sat Jan 09, 2016 7:43 am
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

Is this actually correct as shifting by 32 bits is meaningless? I don't think it's meaningless (i.e. undefined) - rather, the result (for LSR/LSL) should be zero. The ARM2 data sheet does carefully define the expected shift behaviour when the shift amount is 32, and >32. So I think we need to make ...
by fordp
Fri Jan 08, 2016 8:34 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I would have thought this: while (k > 32) k -= 32; Would be better as: k &= 0x1F; There's a subtle, but important difference for k = 32, 64, 96 etc - the while will return 32, the & will return 0 Probably fixable with some checks on the initial value of k: k = ((k & 0x1f) == 0 && k != 0)?32:(k&0x1f...
by fordp
Fri Jan 08, 2016 7:39 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I have been looking at m_icount in arm.c and it is not clear what it does and if it serves any purpose. Can anybody work out what it does. It seems to be be set to 1 and then decremented by more than one so will surely go to zero or negative straight away? It allows the mame emulation to execute mu...
by fordp
Fri Jan 08, 2016 7:10 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I have been looking at m_icount in arm.c and it is not clear what it does and if it serves any purpose.

Can anybody work out what it does. It seems to be be set to 1 and then decremented by more than one so will surely go to zero or negative straight away?
by fordp
Fri Jan 08, 2016 5:29 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

The location of the GPIO registers is also different on the Pi2.

This is why I kept the GPIO Address locations in a pointer on the SPI Driver.
by fordp
Fri Jan 08, 2016 4:20 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

All but the Raspberry Pi 2 should work, there may be an issue with those with less than 512MB of RAM but fixing this should be trivial as we do not need that much RAM.
by fordp
Fri Jan 08, 2016 2:16 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

Strange I will have to build it myself and find out what is going on as there should be a lot less instructions in the path!
by fordp
Fri Jan 08, 2016 10:45 am
Forum: 32-bit acorn hardware
Topic: Reverse Engineering The iPhone’s Ancestor (Acorn ARM Eval)
Replies: 7
Views: 1612

Re: Reverse Engineering The iPhone’s Ancestor (Acorn ARM Eval)

Apple and the Newton was the reason ARM was spun out as Apple wanted a separate entity.

Nokia and early GSM phones were what drove the creation of the AMR7TDMI including the Thumb instructions and these two events are both very important in the history of the ARM processor.
by fordp
Thu Jan 07, 2016 11:34 pm
Forum: 32-bit acorn hardware
Topic: Reverse Engineering The iPhone’s Ancestor (Acorn ARM Eval)
Replies: 7
Views: 1612

Re: Reverse Engineering The iPhone’s Ancestor (Acorn ARM Eval)

We are working on this getting this system running again using smoke and mirrors or at least a raspberry Pi over in the 8 bit hardware section!
by fordp
Thu Jan 07, 2016 8:37 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

Maybe try this: void copro_arm2_main(unsigned int r0, unsigned int r1, unsigned int atags) { static unsigned int last_gpio = (RST_PIN_MASK |IRQ_PIN_MASK | NMI_PIN_MASK); // Initialise the UART RPI_AuxMiniUartInit( 57600, 8 ); printf("Raspberry Pi ARM2 Client\r\n" ); copro_arm2_init_hardware(); enabl...
by fordp
Thu Jan 07, 2016 1:49 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I would have thought this:

Code: Select all

while (k > 32) k -= 32;
Would be better as:

Code: Select all

k &= 0x1F;
by fordp
Wed Jan 06, 2016 7:01 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I would guess inline assembler and simply use the equivalent modern ARM instructions.

Sorted!
by fordp
Tue Jan 05, 2016 9:36 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I guess getting the debugger going would help here. Most of the numbers are only a fraction i.e. 0.00001 out but the 10 showing as zero is very strange. I am guessing the code will work the same on the DE1 version or the Matchbox LX9? I do have my Matchbox LX9's now but it will be a few days before ...
by fordp
Tue Jan 05, 2016 5:40 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

I would guess this is a bug in the soft ARM where it is not reliable in loading the vectors.

The reason I say this is that it does not happen at start-up which is the only time I would expect the vector to actually be zero.
by fordp
Tue Jan 05, 2016 1:28 pm
Forum: 8-bit acorn hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 90023

Re: Raspberry Pi Zero as a Second Processor anyone?

hoglet wrote: I had a play this afternoon, and had some limited success:
Dave
Wow Dave,

I think that is a bit of an understatement.

Great work.
by fordp
Mon Jan 04, 2016 5:52 am
Forum: 8-bit acorn hardware
Topic: Matchbox co-processor new users
Replies: 113
Views: 14182

Re: Matchbox co-processor new users

I think we should add a new command that loads images in to 1 and 3 or 2 and 4 with a single command. My drives are all double sided.

The images would be consecutive in the MMB.

Any preferences on a command name for this?
by fordp
Wed Dec 30, 2015 6:06 pm
Forum: acorn atom and acorn system series
Topic: Matchbox sized 6502 / Z80 / 6809 Co Pro
Replies: 1214
Views: 150502

Re: Matchbox sized 6502 / Z80 / 6809 Co Pro

Great work Dave, I am looking forward to getting my Matchbox LX9 connected to my Raspberry Pi Zero. I intend to power it from the Tube 5V supply so power sequencing should not be an issue.

Cheers.

Go to advanced search