Search found 1036 matches

by fordp
Tue Dec 15, 2015 5:26 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

The emulated 6502 Co Pro running BASIC II gives: - a combined average of 1.89MHz with the L1 cache disabled - a combined average of 3.63MHz with the L1 cache enabled Dave It's also too slow to keep up with the initial language transfer; approx 50% of the bytes are being missed. This makes no sense ...
by fordp
Mon Dec 14, 2015 10:22 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

OK, well that's a few hours I'm not going to get back. :( Dave If this was easy everybody would do it. On second thoughts, not many would but I think it is a more logical pursuit than climbing mountains ;) I spent a few more minutes on OpenOCD. I have come to the conclusion it does not like me. I n...
by fordp
Mon Dec 14, 2015 6:24 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Having looked a Fake86 again I think this is way better https://github.com/adriancable/8086tiny. We will need to add the same 80186 instructions that Dave added added to the Zet core but it is so small that should not be hard. It is maybe not the fastest but I think the Pi version will be close to t...
by fordp
Sun Dec 13, 2015 9:51 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

The good news is I got a full tool chain installed including Eclipse and managed to repeat my success that I had on Windows pretty quick. It was building the code and all looking great. Linux would certainly be a quicker system to get up and running. Maybe Eclipse also contributes to the memory pre...
by fordp
Sun Dec 13, 2015 9:43 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Despite not getting JTAG going I thought I should patch the Tube Client to enable the JTAG interface at boot. If I have done it correctly then you should be able to attach at run-time and debug the Pi application. I may borrow a JLink interface from work next week and try yet again to debug the appl...
by fordp
Sun Dec 13, 2015 8:15 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Well that is yet more hours I am not going to get back! I got my Linux hacking machine up and running. It was an old machine I took out of service a couple of years ago. It had 2GB of RAM. Its seems Ubuntu cannot do anything serious with 2GB of RAM these days! It spent a long time thrashing the hard...
by fordp
Sun Dec 13, 2015 12:56 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I have made some headway and managed to build the Tube Client at this end using the "GNU ARM Eclipse" environment. This was down to the missing linker script in the project on Github. I have added my script to Github and when I get a working JTAG debugger I will write the whole think up on the Wiki....
by fordp
Sat Dec 12, 2015 11:33 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I have my Linux hacking machine running now.

I have spent 10 minutes with openocd and things are doing exactly what they should.

It will take a few more hours tomorrow to get it useful as a software platform but I am quite hopeful I can do some debugging!
by fordp
Sat Dec 12, 2015 9:17 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Well I have made progress of sorts. I have rewired my SPI Tube connection between my DE1 and Pi and using the kernel file from your latest zip I get the correct boot of the BEEBFPGA. I am in the progress of turning an old PC in to a Linux hacking machine. I can see you are making BBC SD Cards progra...
by fordp
Sat Dec 12, 2015 4:49 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Ford, Here are some build artefacts that might help you in your debugging of your Eclipse build: --- Snip --- Dave Thanks for that. I managed to get my build system to spit out a mixed c and assembler listing by adding a post build stage and calling object-dump (the ARM version of course). My code ...
by fordp
Fri Dec 11, 2015 11:09 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Well tomorrow I setup a Linux machine for my Pi work. I have just wasted yet more hours trying to get OpenOcd going on Windows. There is so many traps to fall into. My old Signalyzer interface is not supported on 64bit Windows as there is no driver. Yet there is a driver for the FT2232 chip but you ...
by fordp
Fri Dec 11, 2015 8:13 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Wow I had no idea the Co-processor emulators already existed. (http://mdfs.net/Apps/Emulators/Tube/) Amazing! Looks like this "Pi Zero Second Processor" will have a LOT of existing software it can run unmodified :D It also looks like my way of adding a 80186 soft-core is a crass way to do it? I have...
by fordp
Fri Dec 11, 2015 5:56 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Ford, OK, final pin assignments, that should work for both revisions of the Model B: - Pin 11 (GPIO17) for IRQ - Pin 12 (GPIO18) for NMI - Pin 26 (GPIO7) for RST I had tried this before, but neglected to spot that the SPI code was also configuring Pin 26 / GPIO7 for as an output for SPI_CE1_N. I've...
by fordp
Thu Dec 10, 2015 10:23 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I have 4 Pi in total. The one I am using is the second version with the mounting holes.

I am not sure the JTAG reset is needed or useful as you loose control after Reset anyway. It is not essential anyway.

FordP
by fordp
Thu Dec 10, 2015 9:54 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

OK I have added some 80186 files they are not used at the moment but may be linked in, it depends how smart GCC is. You can exclude all the files from the cpu80186 directory as they are of no use to a pure ARM Copro. I wanted to add them so both of us could see how a soft processor may fit in with t...
by fordp
Thu Dec 10, 2015 7:50 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

OK there is a problem I should have mentioned before. The SPI Tube Interrupts are clashing by using the same pins we need to use for the JTAG. Could you move them to a couple of spare pins? The JTAG details are here: https://github.com/fordp2002/ArmCopro/wiki/Raspberry-Pi-JTAG I think there are enou...
by fordp
Thu Dec 10, 2015 6:14 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Hi Dave, I am back hacking again, I will get back to the JTAG at some point but I did not quite get there with that. Maybe I should use two Raspberry Pi's like you said earlier as my big issue was Windows! I will get it working I will never get my 80186 working without JTAG. Strange thing is just no...
by fordp
Thu Dec 10, 2015 12:26 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

http://infocenter.arm.com/help/index.js ... index.html

This web page has word and numbers on it.

My favourite sentence "This operation must be carried out in a privileged mode.".

I like it as it is short and I can pretend I know what it means ;)

FordP
by fordp
Thu Dec 10, 2015 11:41 am
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I am pretty useless at writing Assembler and know little of the ARM11 especially the floating point bit. I have one input however is that if you feed the correct chip details (VFP I think) then GCC should check the sanity of the machine code it is generating. I can only think of two reasons it would...
by fordp
Thu Dec 10, 2015 11:35 am
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

hoglet wrote:The other option for JTAG interfaces is a second raspberry Pi.
Dave
Yes I saw this. Lucky you have two Raspberry Pi's then ;)

FordP
by fordp
Thu Dec 10, 2015 9:59 am
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Dave you were asking about JTAG interfaces. I think I would go for this module: http://uk.farnell.com/ftdi/ft4232hq-mini-module/mod-usb-to-serial-fifo-ft4232h/dp/1697466 It can run up to 2 JTAG interfaces and up to 4 Uarts and is coming from our Scottish friends FTDI directly so no trouble with driv...
by fordp
Wed Dec 09, 2015 9:30 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I am getting the following linker errors at the moment on "PiTubeClient": Building target: PiTubeClient.elf Invoking: Cross ARM C Linker arm-none-eabi-gcc -mcpu=arm1176jzf-s -march=armv6zk -marm -mfloat-abi=hard -mfpu=vfp -O0 -fmessage-length=0 -fsigned-char -ffunction-sections -fdata-sections -g3 -...
by fordp
Wed Dec 09, 2015 9:10 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

My intentions are to layer the code to make it simple to understand and extent without slowing it unduly. Could you make any big structural changes on a branch please. What are you trying a achieve with additional layering? The modularity to slot the 186 emulation along side the native ARM client? ...
by fordp
Wed Dec 09, 2015 8:56 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Thanks Dave for giving me access to the software on Github. I will do my best to keep it in a good state. My intentions are to layer the code to make it simple to understand and extent without slowing it unduly. I will work towards my 80186 Second Processor but it may take me some time as I have lot...
by fordp
Wed Dec 09, 2015 8:41 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I would guess RiscOS BBC Basics will not follow the same "Tube/ Acorn OS" Api so may be harder to port than the Evaluation System version? Yes they do, as the Tube API is just a subset of the RISC OS API. The Tube API is SWIs &00 to &0F (OSWRCH to OSGBPB). The RISC OS API just adds onto those. Spro...
by fordp
Wed Dec 09, 2015 8:17 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Hardware Floating Point was rare on ARM11. There seem to be lots of variants of the Hardware Floating point types in the GCC Compiler so maybe the code is just not compatible. On the other hand it may be buggy. At least there a pointers in the code as to where the floating point could go. My 80186 c...
by fordp
Wed Dec 09, 2015 7:25 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

The benchmarks show no evidence of a hardware floating point. I would expect it to be a much higher uplift on the Sprow ARM7TDMI which definitely does not have hardware floating point unit. It does not even have integer multiply which is another candidate for speed up. Most of the modern Cortex M do...
by fordp
Wed Dec 09, 2015 5:37 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

hoglet wrote:
Oh, and I think the Pi's instruction and data caches are actually still turned off :shock:

Dave
I think so too!

We also have the possibility to rewrite the BASIC with hardware floating point too!

FordP
by fordp
Wed Dec 09, 2015 5:33 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

Hi Dave,

Well done.

Yippe, is that the fastest BBC Micro in the world ;)

FordP
by fordp
Wed Dec 09, 2015 2:37 pm
Forum: hardware
Topic: Raspberry Pi Zero as a Second Processor anyone?
Replies: 988
Views: 75408

Re: Raspberry Pi Zero as a Second Processor anyone?

I was surprised my hack stayed in there so long. That was a first attempt at a driver.

Sorry it did not work!

I intended to implement DMA so did not spend much time on the first hack.

FordP