RISC OS on the Raspberry Pi

Using a debug version of the ROM image and with a serial terminal connected (which requires some level-shifting circuitry for the headrer plug) then a command line RISC OS environment would be feasible. However with no USB drivers (and thus no Ethernet) storage would be tricky….

Let’s hope the USB drivers will be finished before people start knocking on the door!

Maybe the ROOL boys will have a surprise for us all at Wakefield!

naivesnob

Is that a Raspberry Pi that it’s running on? Does that mean the USB drivers are now working?

I doubt it. But storage via SD could be coming on slowly but surely.

OK if storage by SDcard is coming over the horizon first then one possibility is to use one Pi as a serial terminal running Linux with a USB keyboard, connected to another Pi using RISC OS with SD card storage and linked to each other using the serial port on the headers. No level shifting required.

Then someone can produce a header serial port with level shifter so that a mouse or keyboard can be connected directly to the RISC OS machine.

There may be many embedded applications that would not actually require a keyboard AND mouse but perhaps just a serial mouse alone.

I’ve ordered an RS232 level shift chip in order to get a serial mouse safely paired to my raspberry pi. Should be here by next week. Can anyone get me started creating the necessary risc os build on my sd card before it arrives please? I actually have a RISC OS onscreen keyboard module from a hacked Bush set-top-box with a PACE ARM7500FE so that’s entirely possible.

There are (AIUI) two difficulties: the RISC OS ROM image needs to be ‘packaged’ into an image file which can be done in Linux command line using a command of the form:

mkimage -A arm -O linux -T kernel -C none -a 0×81000000 -e 0×81000000 -n “RISC OS” -d <the rom> kernel.img

(the options may need to be adjusted to call for an ‘image’ file as the desired output). The file ‘kernel.img’ then replaces the existing one on the FAT partition of the SD card.

The second problem is that the USB drivers in the present ROM image do not work with the Raspberry Pi yet (which leaves you without a mouse or keyboard). It is possible that a different entry point than 81000000 is needed to tell the ROM that it is running on a Pi.

You also need to build a level-shifting board to be able to use RS 232 C. Let me know if you succeed in this as I shall be following in your footsteps as soon as I get the Raspberry Pi I have ordered from Farnell – I am about three thousand and something in the queue and so might get something in early May…

Just to clear up some confusion, mkimage is a u-boot thing and RPi doesn’t use u-boot. The bootloader will take a raw Linux kernel in zImage format. Actually the requirements for tricking the bootloader into thinking you have a correct zImage file are pretty minimal – a magic string and some entry points (with no need for any compression) – such that creating an image from scratch that’s bootable isn’t too hard. Indeed, the OMAP3 RISC OS port already has support for pretending to be a Linux kernel.

On serial level shifters, there’s a variety of boards on ebay – either with a USB-serial chip or plain RS232. For about £4 I’d recommend trying one of these so you don’t have to build your own. We’re currently having a play with a few at the moment.

For the builds we’ve had from Adrian (that we haven’t had the OK to release yet), I/O is via a simple Windows app that just grabs keyboard/mouse input and packages it in a simple protocol. It would be fairly trivial to write a RISC OS version (or indeed a Python/C/Java/Haskell/F#/whatever version) to feed in data – the main issue is you need to translate everything into RISC OS internal key numbers (is there an easy-to-borrow table somewhere?).

Hi all i take delivery of my first Pi next week where can i get a Risc OS image for testing???

Update the delivery van just dropped off not one but two Pi this morning, so as it’s got to be the best day ever 2 for 1 is like winning the lottery.
first job is to get all the parts together first presentation to the Vic school board at St Andrew’s place in Two weeks it would be fantastic if we could show them Risc OS as well as linux running on the Pi.
I personal think it is a great fit for primary Education, i will sign off now as i am going too play.

I also would like to get a RISC OS image for it.

If anyone expects me to contribute to porting a USB stack to it, how on earth am I supposed to do that when there’s nothing to work with?

If the Ethernet is working – could the module “vncserver” be used?
- to control the mouse/keyboard.
How difficult would it be to run a ‘ARMini/Pi’ over the Internet
- for testing progs?

You first need working USB before you can get working Ethernet. Maybe you can get something like vncserver over a serial port working? But I think that will be very slow.

If it were just using the mouse and keyboard part (There was a program VNCInput, that allowed control of a second machine using its own display, the screens were put side by side.)

You can try phlamethrower’s (Jeffrey Lee) VNC server with “displayupdates=0”. That should be 32-bit.

first thoughts on the Pi tried 3 versions of linux today all i can say is lets get a move on the port of Risc OS if ever a device needs a small OS this is it.
I allowed 1 Hour for each dist,
first Debian “squeeze” this is the image they recommend you use, results mixed starts well would not load a GUI command line only needs more work.
Second Fedora 14 Remix download flashed image worked first time but very slow in GUI not bad in Text mode.
Third Arch Linux ARM small image aims for simplicity and full control to the end user. Notes that this distribution may not be suitable for beginners.
Verdict if we can get the same speed we see on a Risc PC out of the Pi we would win this race just the speed of the desktop without any help from the GPU,
would be a sight to see.
will report back as an when i do some more tests over the next week but time is getting tight, we move to Perth at the end of next month, still need to school board demo before, we go to the new office.

You can try phlamethrower’s (Jeffrey Lee)

There have been a number of references to software on the phlamethrower site. However, I never have much success accessing it. Netsurf comes up with the message ‘Could not resolve host:www.phlamethrower.co.uk (Could not contact DNS servers)’. Is this my end, or maybe PlusNet causing the problem?

Is it worth while trying OpenDNS servers.

win this race just the speed of the desktop

The CAS RPi manual and “educational launch SD card” presumably won’t include RO without help from us here (along with Adrian’s sources, Broadcom authorisation, CTL licensing).

Are the Linux distributions intended to be used from separate individual cards?

first Debian “squeeze” this is the image they recommend you use, results mixed starts well would not load a GUI command line only needs more work.

You can get it to a GUI by editing the runlevel in /etc/inittab I did; it worked. It was dog slow, but the problem is probably compatibility between my SD/SDHC cards with the RPi’s hardware and firmware. I’ve ordered some more SDHC cards.

I have variable results with the phlamethrower domain all round (email and web). It worked today, but in the past I’ve been unable to email Jeffrey for days at a time :( And yes, it is probably plusnet, as I’m using them here too. :(

I had problems with Plusnet, I moved over to Zen & never looked back!

Are the Linux distributions intended to be used from separate individual cards?

Their suggestion is Yes. You can have several images on one SD card but you need to rename them to get it to start up with a different distro.

after some more testing it started to come back to me, that you don’t need to edit the run level all you need to do is type startx to start the GUI it is slow but it is the best of the bunch that i have tested so far.