Advice on switching microntrollers

I don't see what you have against unobtainium. It is a wonderful material. It's just a shame it's so expensive. ;>

Have you looked at the MSP430 series from TI? Quite a bit of your requirements list covered (although I think not all). 14 bit ADC's on some processors in the family 12 bit on others.

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Paul E. Bennett ....................
Forth based HIDECS Consultancy .....
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Since you already have a reasonable range of 8 bit uC's, there would seem little point adding another one. just to get a learnng curve....

I'd look at the ARM families, Philips presently have the cheapest/smallest start at $1.50, and Atmel have ones with Ethernet. Pretty much everyone makes some ARMxx variant, including Freescale and TI.

-jg

Hello Will,

Nah. Just different opinions.

I'd side with Paul. The MSP430 series is really nice and their ALU runs at 16 bits. Almost feels like getting into that new V8, including the financial pain that comes with that. Don't expect them to be much under a Dollar for the bar bones versions, no matter what TI marketeers claim. Once you want ADC and some other niceties expect to pay over $2. So, right now they can't play in the Atmel price range.

All uC I have seen so far do it in hardware timers, or not at all. The MSP is geared nicely here but again it uses the timer. For truly dedicated PWM you need to look at DSP.

This is where the MSP430 truly excels. I don't know if any other uC can go that low in power. They even have a mode where you can keep a RTC running yet it sips only a couple uA or so.

Regards, Joerg

NEC V850 series. Unfortunately the tools I used were Greenhills. Expensive crap, but V850 might be supported by GCC now.

John

a list of current targets for gnu/gcc

[shopping list snipped]

Get the biggest FPGA or CPLD you can, and write the one of your dreams. ;-P

Personally, I rather like microprogramming, albeit I'm kind of a solution in search of a problem in that respect. For example, my first real computer was a "Scelbi 8-H", which had an intel 8008 and 256 bytes of RAM. Eight toggle switches and three pushbuttons on the front panel, and three rows of 8 LEDs: H, L, and M. The buttons were, "Interrupt", "Step", and "Run". They weren't debounced, which was a very powerful learning experience! ;-)

I guess the point is, the 8008 "assembly language" mapped almost character for character onto the machine instructions, which, when I saw the diagram of the architecture of the 8008 Ah, rats. Most of the google hits are about history and crap - I was hoping for a diagram. But it's so freaking simple that the program is the equivalent of a microprogram. Like, the instructions are in octal, two bits of op code, and three bits each for usually the destination register (A,B,C,D,E,H,L,M) and three for the source register (see above.) "3" was the opcode for "move". And when you look at the architecture diagram of the 8008, you can see that when the instruction enters the black box, it's split up into opcode, destination, and source - which go directly to the data selectors on the inputs or outputs, as designated! Oh, of course, there are other opcodes, but they had sub-codes, which still only needed one more level of decoding - my point being, that the program for an 8008 was, essentially, a microprogram. :-)

Cheers! Richh

Cheers! Rich

...

Or, work on new approaches to task sharing. What ever happened to The Connection Machine? I remember reading a thing in some mag, where some guy said, (I paraphrase) "Well, the only problem we have now is how to program the thing!" "Ah, but we have an endless supply of programmer flesh - undergrads!"

But nothing ever seems to have come of it.

Thanks, Rich

You do of coursde realise that I2C and SPI just need a couple of port pins.

There's nothing special about the hardware. Simply write your own device handler.

Graham

Danny Hillis is having more fun building crazy 10000 year clocks, and big ole robots, out of Glendale CA, at a place called Applied Minds.

For more direct-mapped nostalgia, compare the instruction set of Data General Nova and the Texas Instruments SN74181 ALU chip.

Another pretty easily microcoded example is the Digital PDP-11.

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Tauno Voipio
tauno voipio (at) iki fi

The MLF package is a LOT smaller (9 x 9 mm), and not that difficult to work with. (Much easier than BGA).

Look at the various new generation of ARM based MCUs. There are quite a lot available from manufacturers such as Philips, Atmel, ST, Analog Devices, TI and Freescale.

Regards Anton Erasmus

If one need to bit-bang these ports, then one should just note the I/O speed of the MCU. On many of the new ARM MCUs, the possible I/O toggling speed is a lot lower for a specific system clock speed than for the 8-bit MCUs.

Regards Anton Erasmus

Aahhhhhhhh!!!!, dreams of hypercubes....

There have been some interesting approaches to programming meshed and close coupled processor cores. Some of them have been reported in The Journal for Forth Applications Research. Forth was apparently the bring-up language for one of the MPP's.

--
********************************************************************
Paul E. Bennett ....................
Forth based HIDECS Consultancy .....
Mob: +44 (0)7811-639972
Tel: +44 (0)1235-811095
Going Forth Safely ....EBA. http://www.electric-boat-association.org.uk/********************************************************************

Click on PSoC Mixed-Signal Controllers.

The in-circuit emulator is not free.

Cheers, John

How is that so? I mean, is there some kind of long propagation delay or what? I have played around with PICs for years, but I have been gaining interest in the ARM micros. This sounds like a serious issue to me.

Why not just switch to the ATmega128 in QFN package = 9 x 9 mm. The AT90CAN128 will give you the CAN controller. The ATmega644 will give you at least 64 kB memory in a 7 x 7 mm QFN. The AT91SAM7 could be alternatives, but there is no 32 KHz clock.

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Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may bot be shared by my employer Atmel Nordic AB

ARMs typically use the AMBA bus where you connect the CPU to the 32 bit Advanced System Bus (ASB) and then there is a bus bridge to an Advanced Peripheral Bus (APB). The Bus Bridge will add delays so you find bit banging will take 5-6 clocks at best due to delays. The Philips LPC was so bad at this, that some new parts have the PIO on the ASB bus instead of on the APB bus. The AT91SAM7 is limited by the I/O buffers but H/W can shuffle bits at 25-30 Mbps.

--
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may bot be shared by my employer Atmel Nordic AB

I had an opportunity to use an editor on a PDP-11 and cross-assembler to write some test stuff for an IMP-16:

The company had the naked boards in stock, to use in another thing; they didn't have that box. There's more stuff: And, I believe I've seen the 74181s, or maybe AM2903s, on a PDP-11's CPU board. I also once worked on an all-TTL "microprogrammable processor", but it was 32 bits, and was used to test disk drives. That one had even TTL RAM. The instruction cycle was 168 ns, which was unheard of at the time. And, the thing that really makes the microprogram stand out as a microprogram is the "next instruction" field in the instruction. The G-15's machine language was like that too, but that was for timing, since all of the memory was circulating on a magnetic drum.

Ah, I nostalge. Sorry.

Cheers! Rich

sounds like a job for a dspic to me. Maybe a dsPIC30F2010. They are pretty nice, particularly if you have pic16 experience.

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Regards,
  Bob Monsen

Beyond the natural numbers, addition, multiplication, and mathematical 
induction are intuitively clear.
- Luitzen Brouwer (1881-1966) (intuitionist)