ARM Development basics

Hello peoples,

I want to use LPC2929 ARM Microcontroller, The datasheet says it's frequency can go up to 125MHz so should i have to hookup 125MHz crystal :fearful: ?
Coming to the main part, please let me know what's the best compiler for ARM development, please try to list all you know.

Your replay really appreciated.
Thank you in advance.

This is probably not the best place to ask this sort of question.

Most high-frequency-capable microcontrollers have fancy clock controller circuitry that includes a PLL-based frequency synthesizer that permits various internal clock rates that are multiples of a divisor of the external crystal frequency. So for example, the TI ARM Launchpad I’ve been using creates an 80MHz internal clock from a 16MHz crystal. Operation is a bit complex; read your datasheet. (I think the TI multiplies by whatever is needed to reach 400MHz, and then divides by 5, or something like that.)

Variations of gcc are probably the best compiler for ARM, unless you want to spend money. Many of the commercial vendor-provided environments are based on gcc, or you can put together an environment yourself. Additional options are Keil (now owner by ARM), IAR, and Imagecraft (Imagecraft is actually rather reasonably priced, but not free.)

Really informative, can you give me some reference to learn about arm very goodly ?
Your help is really appreciated.
thank you.

This would be a start:

AFAIK all LPCs use a 12MHz crystal, the actual CPU speed is determined internally with a PLL.

The LPCXpresso forum ( is a good place to ask about LPC stuff.

As far as getting to know the chip, I would suggest buying an LPCXpresso dev board, but I don’t think they make one specifically for the LPC2929 though. Have a look here, do you really need the 2929.


Dude now your talking, your replay is what i was expecting, thank you for this information.
btw i am not tied with 2929 but i simply want to use a ARM 32-bit microcontroller with good memory, cheap in price and good manufacturer with good documentations (NXP/TI/ST is good for it i think), and this mcu have both, that's why i chooses this.

thank you.

I noticed that Atmel recently announced expansions to their line of ARM Cortex M0+ MCUs:

Only the SAM D20 chips are currently available, but the prices are fairly amazing, they seem to be in the same range as the mega AVRs. Thinking about getting one of their eval boards.

Looking through ASF in Atmel Studio now, trying to figure out how much help it'll be. I've used Atmel Studio some with ATmega and ATtiny MCUs, but haven't delved into ASF, as it didn't seem to have much for the MCUs I was using.

Does anyone have experience with or opinions about ASF? It seems to want to force you into C projects as opposed to C++ which is annoying.

My faves at the moment are:
(1) Teensy 3.1 — inexpensive <$20, 256k flash, 64k RAM, USB, 2xADC 13bits, 1xDAC 12bits, I2C, SPI, CAN, I2S …
(2) TI Tiva Launchpad – inexpensive $12, USB, 256k, 32k RAM, …

Lots of others out there, though.