Page 2 of 7
Re: Raspberry Pi and the MagPi
Posted: Mon May 07, 2012 6:13 pm
by Dajgoro
i remember seeing some arm mcu that had an external bus interface, where you could add external ram(or maybe hardware?).
The STM32F and STM32L (at least) have what's called a 'Flexible Static Memory Controller' (aka FSMC), that among other features, can remap 42 GPIO pins into A[0:25] & D[0:15] as a memory bus to external SRAMs, and the ram then appears as up to 1GB of normal directly-addressable memory.
Is there some sort of IDE software, or something similar for this sort of arm mcu/cpu?
Re: Raspberry Pi and the MagPi
Posted: Mon May 07, 2012 9:18 pm
by BigEd
It doesn't answer your question (I think both cjb and I are using command line toolchains, he with more success) but see the libopencm3 library for examples and extensive documentation - the RM0090 datasheet is the one you want.
Re: Raspberry Pi and the MagPi
Posted: Mon May 07, 2012 11:46 pm
by Dajgoro
Ouch 1315 pages, and i thought that 218 pages for the pic16f877 was much...
Re: Raspberry Pi and the MagPi
Posted: Tue May 08, 2012 7:45 am
by BigEd
The nice library people have done a lot of the work for you. See the
example code for
driving the USB port as a serial device. (There are also examples for blinking LEDs, but USB was never going to be easy.)
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 2:09 pm
by jonb
I have one of these on order and I expect it will be with me in a couple of weeks. As you probably know, it is supposed to be for education, but enthusiasts all over the world have jumped on it because it is so cheap. It is said to be quite slow running a desktop and browsing is painful, but the Broadcom SoC's video core is fast enought to run Quake 3 at 1080i. One problem is that the video core has a proprietary blob and the APIs are not public (although there are libraries that can use it). As I understand it, accelerated Xorg drivers are not there yet. And the LAN, USB ports and CD card adapter are all hanging off an onboard single USB hub, so you can expect that to be a major bottleneck. Still, for £30 it's an interesting proposition. What I wondered is if the GPIO pins could be leveraged as some sort of high speed parallel interface or bus, so we could get some proper fast I/O on it.
About the MagPi magazine; I read it and thought it was nicely presented but the articles were very light in content and amateurish in style. Nevertheless, I think it is great, especially with the listings in there (just like the old days, but without the errors, I hope) and will improve with time.
So who else here has ordered one?
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 2:29 pm
by rwiker
I've ordered one.
Apparently, there are several add-on boards in the pipeline, including one or more from AdaFruit. There's also one called the "GertBoard", which looks like it might be useful for a lot of stuff.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 2:58 pm
by jonb
Yes, with Gertboard you have lots of Arduino type I/O possibilities. I believe AdaFruit so far produced a prototyping shield that is intended to plug onto the GPIO header, but more are sure to follow. I'd be interested in applications for the other two ports on the board that are not well known - the camera and LCD panel connectors. I was wondering if the camera connector could support some sort of high speed I/O.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 3:11 pm
by BigEd
I have one on order but no plan on what to with it. I think it should boot direct into an application - perhaps a beebulator.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 3:12 pm
by BitWise
I've had one on order for a while. I'm busy porting my CESIL environment to Linux JAVA to give kids an authentic glimpse of 1970's UK Computer Science education.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 5:58 pm
by Dajgoro
Did you order them for real, or have you just registered your interest?
I want one too, and my friends also.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 6:03 pm
by BigEd
Ordered for real, in my case. Farnell took orders, RS took interest, and then later allow you to place a hard order.
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 6:09 pm
by Dajgoro
When do you expect it to arrive?
Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 7:02 pm
by jonb
I've had one on order for a while. I'm busy porting my CESIL environment to Linux JAVA to give kids an authentic glimpse of 1970's UK Computer Science education.
CESIL?? You sadist!
ha ha

Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 7:03 pm
by jonb
When do you expect it to arrive?
Farnell UK delivery next week according to their latest update

Re: Raspberry Pi and the MagPi
Posted: Fri May 11, 2012 7:14 pm
by jonb
I have one on order but no plan on what to with it. I think it should boot direct into an application - perhaps a beebulator.
Hi Ed
Not sure I agree. Modern dev environments are not like the BBC Micro - and we really don't want to impose 80's micros on our kids, do we? On the other hand, my children enjoy playing with the Beeb, despite having a 2011 iMac to muck about on.
I think the Pi's current problem is the software stack isn't mature at all; there are crashes, slowness, and general lack of development. The Foundation is relying on a community effort to get the thing ready for its educational release, at which point the "official" distro should be on a more stable, even keel. At least, I hope!