NXP Cortex M3 chips?

[Bill Martin]

Hi,

Anyone have experience with NXP ARM micros? Or anybody else's for that
matter. Looking at the embed proto board & wanting to know if the
on-chip boot rom is present in all the NXP ARM chips & how is it
activated in ones own board. It looks like it is wired into one of the
USB ports in some way...anyway, just looking for experiences with using
those parts.
TIA,
bill m

 

[Nico Coesel]

We use the LPC1754/58/68 parts. They work fine, fast and low power.

We program the on-chip flash via jtag. I don't think there is any other boot
mechanism.

Actually there is. I always use the internal bootloader to load
software through the serial port. Some devices with USB have an
extended bootloader which can make the microcontroller act as a USB
stick so you can drag & drop the firmware into the controller using
Windows explorer. How about that

 

[Bill Martin]

We use the LPC1754/58/68 parts. They work fine, fast and low power.

We program the on-chip flash via jtag. I don't think there is any other boot
mechanism.

One warning: the ADC doesn't seem to be as linear as spec'd.

Thanks for this, one question re. ADC's: are you referring to the 10 bit
or 12 bit ADC's, or all of them?

 

[Bill Martin]

The mbed and lpcxpresso boards use a 2nd micro to go usb->jtag.
You can actually cut off the programmer part on the lpcxpresso
board but you have to use the code red ide (others may work
but I did not go that far).

I don't see anything looking like another micro on the mbed board, but
since all I get from the schematic link on nxp.com is a black box, it's
hard to be sure...have not checked out the lpcexpresso board yet but
will have a look.

I think all of the M3 have the boot loader. You can check the
data sheets. It's a simple setup that lets you program the part
via UART0. If you are just playing around with the parts you can
use FlashMagic to program. Some of the chips have ROM
drivers for the peripherals. Kind of a built in driver library.
This is not the same as the flash programming/ boot loader code.

The mbed and lpcxpresso boards are both easy ways to get started.
Mouser has the lpcxpresso board for $23.75 now days.

the price is right, as they used to say!

 

[Bill Martin]

Actually there is. I always use the internal bootloader to load
software through the serial port. Some devices with USB have an
extended bootloader which can make the microcontroller act as a USB
stick so you can drag & drop the firmware into the controller using
Windows explorer. How about that

That one feature is enough to make me want to look further, hence the
questions hear. It's Linux friendly, no funky Windows drivers required...

 

[rickman]

Hi,

Anyone have experience with NXP ARM micros? Or anybody else's for that
matter. Looking at the embed proto board & wanting to know if the
on-chip boot rom is present in all the NXP ARM chips & how is it
activated in ones own board. It looks like it is wired into one of the
USB ports in some way...anyway, just looking for experiences with using
those parts.
TIA,
bill m

It's pretty common for these sorts of parts to include a boot function.
Sometimes it is in ROM and sometimes it is in the Flash and can be
overwritten if you wish (or by accident).

I haven't worked with any of the CM3 parts yet (or CM4s for that matter)
but have worked with older Atmel ARM 7TDMI parts. They included a boot
loader that would work through the serial port or USB. I think it
required a proprietary comms program on the PC which likely means
Windows only.

I think you will find all of the major vendors do something similar.

Rick

 

[[email protected]]

It's pretty common for these sorts of parts to include a boot function.
  Sometimes it is in ROM and sometimes it is in the Flash and can be
overwritten if you wish (or by accident).

The build in boot loader is generally in a "hidden" or protected area
of
the flash so with out jumping quite a few hops it is hard to erase

I haven't worked with any of the CM3 parts yet (or CM4s for that matter)
but have worked with older Atmel ARM 7TDMI parts.  They included a boot
loader that would work through the serial port or USB.  I think it
required a proprietary comms program on the PC which likely means
Windows only.

I think you will find all of the major vendors do something similar.

The vendor tools maybe windows only but, the protocol is usually open
and
I think pretty much all of them have an open source tool available
that
can be made to work on anything that can compile c



-Lasse

 

[Bill Martin]

The build in boot loader is generally in a "hidden" or protected area
of
the flash so with out jumping quite a few hops it is hard to erase


The vendor tools maybe windows only but, the protocol is usually open
and
I think pretty much all of them have an open source tool available
that
can be made to work on anything that can compile c



-Lasse

We will see soon. Just ordered one of the lpcexpresso boards play with &
see what can be done without Windows. Not that I wouldn't use Windows if
it's the best way to go...just not first choice.

-bill m