Forums

Micro with USB ISP

Started by Alexander Kane March 25, 2011
I'm after a microcontroller with USB ISP right out of the box with
support from the micro's regular tools.
Important are a small footprint, though preferably not QFN or anything
that can't be hand soldered, and that it is relatively cheap.
This microcontroller doesn't need a whole lot of grunt, so an 8-bit or
16-bit would be fine.
Thanks for your help.
I should clarify: by regular tools I mean the software... the idea is
to program the micro with just the USB cable (plugged into my board
ofcourse), rather than a programmer device.
On Mar 24, 7:18=A0pm, Alexander Kane <ajpk...@gmail.com> wrote:
> I should clarify: by regular tools I mean the software... the idea is > to program the micro with just the USB cable (plugged into my board > ofcourse), rather than a programmer device.
This will do what you need: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3D190516156244
On 03/25/2011 04:15 AM, Alexander Kane wrote:
> I'm after a microcontroller with USB ISP right out of the box with > support from the micro's regular tools. > Important are a small footprint, though preferably not QFN or anything > that can't be hand soldered, and that it is relatively cheap. > This microcontroller doesn't need a whole lot of grunt, so an 8-bit or > 16-bit would be fine. > Thanks for your help.
LPC1342 (or 1343) comes to mind. Available in LQFP48, and has built in boot ROM that can present itself as a USB mass storage device where you can simply copy the firmware to. Tools can be downloaded here: http://lpcxpresso.code-red-tech.com/LPCXpresso/ (Free for small projects)
In comp.arch.embedded,
Alexander Kane <ajpkane@gmail.com> wrote:
> I'm after a microcontroller with USB ISP right out of the box with > support from the micro's regular tools. > Important are a small footprint, though preferably not QFN or anything > that can't be hand soldered, and that it is relatively cheap. > This microcontroller doesn't need a whole lot of grunt, so an 8-bit or > 16-bit would be fine. > Thanks for your help.
Atmel SAM7S can be programmed through USB. Needs a special programming application that can be downloaded from Atmel. Atmel probably has newer controllers with USB programming, I have not checked this recently. -- Stef (remove caps, dashes and .invalid from e-mail address to reply by mail) For your penance, say five Hail Marys and one loud BLAH!
On 2011-03-25, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
> In comp.arch.embedded, > Alexander Kane <ajpkane@gmail.com> wrote: >> I'm after a microcontroller with USB ISP right out of the box with >> support from the micro's regular tools. >> Important are a small footprint, though preferably not QFN or anything >> that can't be hand soldered, and that it is relatively cheap. >> This microcontroller doesn't need a whole lot of grunt, so an 8-bit or >> 16-bit would be fine. >> Thanks for your help. > > Atmel SAM7S can be programmed through USB. Needs a special programming > application that can be downloaded from Atmel.
Assuming you are talking about SAM-BA, this requires jumpers setting on the board to force the SAM-BA code to be copied into the first couple of flash sectors. According to a comment in a Atmel hosted tutorial, there is a limit on the number of times the SAM-BA code can be copied (IIRC, 100 times was mentioned). However, given the quality of code in that tutorial (ie: a lowlevel setup routine called by main.c instead of the startup code, no rule templates in the makefile, but cut and paste makefile sections instead, as well as some linker issues), I would double check the situation with this yourself if you are thinking of using SAM-BA. Simon. -- Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP Microsoft: Bringing you 1980s technology to a 21st century world
In comp.arch.embedded,
Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP> wrote:
> On 2011-03-25, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: >> In comp.arch.embedded, >> Alexander Kane <ajpkane@gmail.com> wrote: >>> I'm after a microcontroller with USB ISP right out of the box with >>> support from the micro's regular tools. >>> Important are a small footprint, though preferably not QFN or anything >>> that can't be hand soldered, and that it is relatively cheap. >>> This microcontroller doesn't need a whole lot of grunt, so an 8-bit or >>> 16-bit would be fine. >>> Thanks for your help. >> >> Atmel SAM7S can be programmed through USB. Needs a special programming >> application that can be downloaded from Atmel. > > Assuming you are talking about SAM-BA, this requires jumpers setting on > the board to force the SAM-BA code to be copied into the first couple > of flash sectors. > > According to a comment in a Atmel hosted tutorial, there is a limit on > the number of times the SAM-BA code can be copied (IIRC, 100 times was > mentioned).
Yes, once the device is programmed, you need te restore the bootloader before you can program it again. For this you need to set the TST pin on power up. We do this via an extra pin on our programming connector on one product, via a jumper and a standard USB connector on another product. The datasheet claims 10000 write cycles. With the need to first write the boot loader, that would imply 5000 programming cycles. More than enough for most applications. I have never run into a programming problem, not even on a test board. If you want to check out if this chip is what you want, get an AT91SAM7S-EK. -- Stef (remove caps, dashes and .invalid from e-mail address to reply by mail) Expense Accounts, n.: Corporate food stamps.
> Assuming you are talking about SAM-BA, this requires jumpers setting on > the board to force the SAM-BA code to be copied into the first couple > of flash sectors.
I think you got this wrong. The jumper on the dev boards is used to erase the flash and NVM bits. The NVM bits indicate whether or not to boot from flash. This is why a chip stops booting from flash and rather runs the SAM-BA code, after you used the jumper. Erasing many times works against the flash cycle limit, just as you say. But it's not a necessity of using SAM-BA. The SAM-BA code is not "copied" into flash ever. You can just as well create a clone of the code, enhance it with a timeout-then-run-my-main-software feature, and flash that. Then you will be able to connect to SAM-BA as often as you want, without ever erasing or flashing anything. Not that this would be very useful, but it demonstrates the point. SAM-BA protocol is documented in the datasheet, and the original binary can be extracted using SAM-BA's memory read commands. Best regards, Marc
Alexander Kane wrote:

> I'm after a microcontroller with USB ISP right out of the box with > support from the micro's regular tools. > Important are a small footprint, though preferably not QFN or anything > that can't be hand soldered, and that it is relatively cheap. > This microcontroller doesn't need a whole lot of grunt, so an 8-bit or > 16-bit would be fine.
This one is really inexpensive from Freescale: http://www.frank-buss.de/MC9S08JS16L/ The AT90USB is nice, too. -- Frank Buss, http://www.frank-buss.de piano and more: http://www.youtube.com/user/frankbuss
On 2011-03-25, Marc Jet <jetmarc@hotmail.com> wrote:
>> Assuming you are talking about SAM-BA, this requires jumpers setting on >> the board to force the SAM-BA code to be copied into the first couple >> of flash sectors. > > I think you got this wrong. The jumper on the dev boards is used to > erase the flash and NVM bits. > > The NVM bits indicate whether or not to boot from flash. This is why > a chip stops booting from flash and rather runs the SAM-BA code, after > you used the jumper. > > Erasing many times works against the flash cycle limit, just as you > say. But it's not a necessity of using SAM-BA. The SAM-BA code is > not "copied" into flash ever. >
Just to make sure we are talking about the same thing, I am talking about the portion of the SAM-BA protocol which is implemented within the MCU and not the host PC portion of this protocol. I checked the AT91SAM7S datasheet (doc6175) in case I was mistaken. I am working from the 30-Aug-10 veersion of the datasheet. From section 8.10 of the datasheet: |8.10 SAM-BA Boot Assistant | |The SAM-BA Boot Recovery restores the SAM-BA Boot in the first two sectors of |the on-chip Flash memory. The SAM-BA Boot recovery is performed when the TST |pin and the PA0, PA1 and PA2 pins are all tied high for 10 seconds. Then, a |power cycle of the board is mandatory. The SAM-BA code always boots from flash. However, since I don't use it (as I write to flash using the JTAG interface), I unlocked the SAM-BA sectors and replaced the copy in flash with my own code. Simon. -- Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP Microsoft: Bringing you 1980s technology to a 21st century world