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any raspberry pi people here?

Started by John Larkin July 18, 2022
On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin
<jlarkin@highland_atwork_technology.com> wrote:

>On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <dp@tgi-sci.com> >wrote: > >>On 7/18/2022 22:13, John Larkin wrote: >>> >>> >>> The pi doesn't seem to have any general counter/timer hardware, like >>> ARMs usually do. I've seen vague references to using the GPU to do >>> timings. >>> >>> I'd like to measure frequencies and timestamp some edges, in the 1 us >>> sort of domain, several channels. I guess we could hang a small FPGA >>> off to the side if pi can't do it. >>> >>> Do pi's have crystal oscillators? I guess we could add one too. >>> >>> >>> >> >>Are you serious about using yet another aliexpress toy for some >>real design? > >https://en.wikipedia.org/wiki/Raspberry_Pi > >Not exactly a toy. But it would save us using up our stock of FPGAs >and ARM chips, and I know a guy who would like to do the programming. >He's a retired Fellow of United Technologies (Collins) who really >likes to code. > > >>Other than the obvious question above, does not ARM have some >>sort of timebase register as part of the core? This might be >>usable to some extent, depending on how much jitter you can >>tolerate. > >The ARM in the pi seems to have none of the usual counter/timer stuff, >so we'd have to do that externally, in a small FPGA probably. We might >have three frequency counters and maybe six edge time stampers in a >FIFO or something. Pretty simple. >
Well, we seem to have only two options, a RaspberryPi or an ARM, one being too small and the other being too large. But there is actually a third option that falls between these two options in size, a Microchip AVR microcontroller. Programmed in a dialect of Ansi C, with code in a flash memory and loaded on startup. .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> Joe Gwinn
tirsdag den 19. juli 2022 kl. 22.29.11 UTC+2 skrev John Larkin:
> On Tue, 19 Jul 2022 10:50:49 -0700 (PDT), John Walliker > <jrwal...@gmail.com> wrote: > > >On Tuesday, 19 July 2022 at 17:08:53 UTC+1, lang...@fonz.dk wrote: > >> tirsdag den 19. juli 2022 kl. 17.04.13 UTC+2 skrev jla...@highlandsniptechnology.com: > >> > On Tue, 19 Jul 2022 09:10:41 -0400, Phil Hobbs > >> > <pcdhSpamM...@electrooptical.net> wrote: > >> > > >> > >jla...@highlandsniptechnology.com wrote: > >> > >> On Mon, 18 Jul 2022 14:05:27 -0700 (PDT), John Walliker > >> > >> <jrwal...@gmail.com> wrote: > >> > >> > >> > >>> On Monday, 18 July 2022 at 21:30:01 UTC+1, lang...@fonz.dk wrote: > >> > >>>> mandag den 18. juli 2022 kl. 22.18.25 UTC+2 skrev Don: > >> > >>>>> Lasse Langwadt Christensen wrote: > >> > >>>>>> John Larkin: > >> > >>>>>>> The pi doesn't seem to have any general counter/timer hardware, like > >> > >>>>>>> ARMs usually do. I've seen vague references to using the GPU to do > >> > >>>>>>> timings. > >> > >>>>>>> > >> > >>>>>> > >> > >>>>>> which version of pi? > >> > >>>>>> > >> > >>>>>>> I'd like to measure frequencies and timestamp some edges, in the 1 us > >> > >>>>>>> sort of domain, several channels. I guess we could hang a small FPGA > >> > >>>>>>> off to the side if pi can't do it. > >> > >>>>>> > >> > >>>>>> using a pi I assume you'll be running some kind of linux I don't see how you > >> > >>>>>> could do 1us timing in linux > >> > >>>>> My RPi2B is loaded with BSD 14 and its nanosleep() function provides 1ns > >> > >>>>> resolution for my iic interface. > >> > >>>> sure as long as your code is running and not interrupted you can busy wait with > >> > >>>> nanosec resolution up to few ms > >> > >>>> > >> > >>>> try reacting on a signal to measure it's frequency or timestamp it .... > >> > >>> > >> > >>> The RasPi 4 is a very nice machine. The CM4 even more so if only you could buy one > >> > >>> at the moment. The CM4 has a PCI-e interface which gives lots of possibilities. > >> > >>> The Beaglebone Black is also good, but it has less RAM than > >> > >>> the Raspi 4 and only has a 100Mbit/s ethernet port whereas the PI 4 has 1Gbit/s. > >> > >>> The extra processors do allow time critical software to be written though. > >> > >>> > >> > >>> There are add-on modules with real time clock chips for the Pi and the BBB. > >> > >>> > >> > >>> Alternatively, look at the RasPi pico board or the RP2040 microcontroller which it > >> > >>> uses. Both of these have the big advantage that they can be bought in large quantities > >> > >>> at the moment. The RP2040 has multiple programmable state machines which > >> > >>> allow very complex i/o operations with precise timing. There are also multiple > >> > >>> counter-timer modules. It is a two-core ARM M0+. > >> > >>> Finally, don't forget the XMOS devices, many of which support USB and/or ethernet > >> > >>> together with deterministic timing and multiple cores. > >> > >>> John > >> > >> > >> > >> We use a Zynq for serious projects, dual ARM and a heap of FPGA, but > >> > >> they are hard to get so I'm conserving them for big stuff. This little > >> > >> tach thing will be dinky. > >> > >> > >> > > > >> > >Well, you probably have a lot of MC68332s still in stock. They're > >> > >pretty nice for timing stuff, if you don't mind using external memory. ;) > >> > > > >> > >Cheers > >> > > > >> > >Phil Hobbs > >> > > > >> > >(Whose first embedded design used a 68332, but never got built) > >> > 68332 has been around for decades and is still available. It's a > >> > wonderful chip. It has 16 TPU timer channels that could do what I > >> > want. But it's big and expensive, and doesn't have USB or ethernet. > >> if USB will do almost any MCU with USB will do > >> > >> https://www.digikey.dk/da/products/detail/raspberry-pi/SC0914-13/14306010 > >> https://www.digikey.dk/da/products/detail/winbond-electronics/W25Q16JVSNIQ/6193768 > >> > >> plenty in stock > >> > >> or if feeling lazy, https://www.waveshare.com/product/raspberry-pi-pico.htm?sku=19310 > > > >Yes, it really is worth looking closely at the RP2040 or the pico board. It is probably > >massive overkill for what you want to do, but at a cost of 1USD for the chip and 4USD > >for the assembled pico board it hardly matters. > >Digikey and Mouser between them have over 166000 chips in stock and around > >33000 pico boards. In the UK Farnell and RS between them have about another > >517000 RP2040 chips in stock. > >There is also a version of the pico with WiFi, but you probably don't need that. > >I am planning to use an RP2040 for a multi-phase switched mode isolated power > >supply. > > > >John > Pico doesn't have ethernet. I'd like that.
https://www.digikey.dk/da/products/detail/wiznet/W5100S-EVB-PICO/15516855
tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn:
> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin > <jlarkin@highland_atwork_technology.com> wrote: > > >On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> > >wrote: > > > >>On 7/18/2022 22:13, John Larkin wrote: > >>> > >>> > >>> The pi doesn't seem to have any general counter/timer hardware, like > >>> ARMs usually do. I've seen vague references to using the GPU to do > >>> timings. > >>> > >>> I'd like to measure frequencies and timestamp some edges, in the 1 us > >>> sort of domain, several channels. I guess we could hang a small FPGA > >>> off to the side if pi can't do it. > >>> > >>> Do pi's have crystal oscillators? I guess we could add one too. > >>> > >>> > >>> > >> > >>Are you serious about using yet another aliexpress toy for some > >>real design? > > > >https://en.wikipedia.org/wiki/Raspberry_Pi > > > >Not exactly a toy. But it would save us using up our stock of FPGAs > >and ARM chips, and I know a guy who would like to do the programming. > >He's a retired Fellow of United Technologies (Collins) who really > >likes to code. > > > > > >>Other than the obvious question above, does not ARM have some > >>sort of timebase register as part of the core? This might be > >>usable to some extent, depending on how much jitter you can > >>tolerate. > > > >The ARM in the pi seems to have none of the usual counter/timer stuff, > >so we'd have to do that externally, in a small FPGA probably. We might > >have three frequency counters and maybe six edge time stampers in a > >FIFO or something. Pretty simple. > > > Well, we seem to have only two options, a RaspberryPi or an ARM, one > being too small and the other being too large. > > But there is actually a third option that falls between these two > options in size, a Microchip AVR microcontroller. Programmed in a > dialect of Ansi C, with code in a flash memory and loaded on startup. > > .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus>
in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? *raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M
On Tue, 19 Jul 2022 14:29:58 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn: >> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin >> <jlarkin@highland_atwork_technology.com> wrote: >> >> >On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> >> >wrote: >> > >> >>On 7/18/2022 22:13, John Larkin wrote: >> >>> >> >>> >> >>> The pi doesn't seem to have any general counter/timer hardware, like >> >>> ARMs usually do. I've seen vague references to using the GPU to do >> >>> timings. >> >>> >> >>> I'd like to measure frequencies and timestamp some edges, in the 1 us >> >>> sort of domain, several channels. I guess we could hang a small FPGA >> >>> off to the side if pi can't do it. >> >>> >> >>> Do pi's have crystal oscillators? I guess we could add one too. >> >>> >> >>> >> >>> >> >> >> >>Are you serious about using yet another aliexpress toy for some >> >>real design? >> > >> >https://en.wikipedia.org/wiki/Raspberry_Pi >> > >> >Not exactly a toy. But it would save us using up our stock of FPGAs >> >and ARM chips, and I know a guy who would like to do the programming. >> >He's a retired Fellow of United Technologies (Collins) who really >> >likes to code. >> > >> > >> >>Other than the obvious question above, does not ARM have some >> >>sort of timebase register as part of the core? This might be >> >>usable to some extent, depending on how much jitter you can >> >>tolerate. >> > >> >The ARM in the pi seems to have none of the usual counter/timer stuff, >> >so we'd have to do that externally, in a small FPGA probably. We might >> >have three frequency counters and maybe six edge time stampers in a >> >FIFO or something. Pretty simple. >> > >> Well, we seem to have only two options, a RaspberryPi or an ARM, one >> being too small and the other being too large. >> >> But there is actually a third option that falls between these two >> options in size, a Microchip AVR microcontroller. Programmed in a >> dialect of Ansi C, with code in a flash memory and loaded on startup. >> >> .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> > >in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? > >*raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M
Far more I/O stuff, and timers et al. Joe Gwinn
On 19/7/22 07:37, John Larkin wrote:
> It seems to be pretty serious, from Broadcom, and it's hard to get > ARMs and ZYNQs these days. It's even hard to get opamps.
If you aren't a determined patriot, there are some impressively inexpensive ARMs readily available from Chinese vendors like GigaDevice and WCH now: <https://www.gigadevice.com/products/microcontrollers/gd32/> <http://www.wch-ic.com/products/categories/66.html?pid=5>
On 7/19/2022 3:18 PM, Joe Gwinn wrote:
> On Tue, 19 Jul 2022 14:29:58 -0700 (PDT), Lasse Langwadt Christensen > <langwadt@fonz.dk> wrote: > >> tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn: >>> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin >>> <jlarkin@highland_atwork_technology.com> wrote: >>> >>>> On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> >>>> wrote: >>>> >>>>> On 7/18/2022 22:13, John Larkin wrote: >>>>>> >>>>>> >>>>>> The pi doesn't seem to have any general counter/timer hardware, like >>>>>> ARMs usually do. I've seen vague references to using the GPU to do >>>>>> timings. >>>>>> >>>>>> I'd like to measure frequencies and timestamp some edges, in the 1 us >>>>>> sort of domain, several channels. I guess we could hang a small FPGA >>>>>> off to the side if pi can't do it. >>>>>> >>>>>> Do pi's have crystal oscillators? I guess we could add one too. >>>>>> >>>>>> >>>>>> >>>>> >>>>> Are you serious about using yet another aliexpress toy for some >>>>> real design? >>>> >>>> https://en.wikipedia.org/wiki/Raspberry_Pi >>>> >>>> Not exactly a toy. But it would save us using up our stock of FPGAs >>>> and ARM chips, and I know a guy who would like to do the programming. >>>> He's a retired Fellow of United Technologies (Collins) who really >>>> likes to code. >>>> >>>> >>>>> Other than the obvious question above, does not ARM have some >>>>> sort of timebase register as part of the core? This might be >>>>> usable to some extent, depending on how much jitter you can >>>>> tolerate. >>>> >>>> The ARM in the pi seems to have none of the usual counter/timer stuff, >>>> so we'd have to do that externally, in a small FPGA probably. We might >>>> have three frequency counters and maybe six edge time stampers in a >>>> FIFO or something. Pretty simple. >>>> >>> Well, we seem to have only two options, a RaspberryPi or an ARM, one >>> being too small and the other being too large. >>> >>> But there is actually a third option that falls between these two >>> options in size, a Microchip AVR microcontroller. Programmed in a >>> dialect of Ansi C, with code in a flash memory and loaded on startup. >>> >>> .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> >> >> in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? >> >> *raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M > > Far more I/O stuff, and timers et al.
The ARM A-family (A=Application) are intended to host more sophisticated environments; primarily made possible by support for VMM. The M-family (and R-family) -- along with the AVRs, et al. -- are intended more for control/mechanisms applications without support for more advanced *operating* system features. Of course, (ARM) licensees can choose to package whatever I/Os they deem appropriate with any family offering. So, once *could* have an I/O-rich A-series processor but you can't (?) have VMM bolted onto an M/R series device (nor the AVRs).
> > Just been biking in the heatwave here, code orange well only 31 C, > wintercoat and hat on.. its cooler on the bike (airflow) than standing still in the sun! >
31 degrees? We call that "summer" :)
onsdag den 20. juli 2022 kl. 00.18.53 UTC+2 skrev Joe Gwinn:
> On Tue, 19 Jul 2022 14:29:58 -0700 (PDT), Lasse Langwadt Christensen > <lang...@fonz.dk> wrote: > > >tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn: > >> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin > >> <jlarkin@highland_atwork_technology.com> wrote: > >> > >> >On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> > >> >wrote: > >> > > >> >>On 7/18/2022 22:13, John Larkin wrote: > >> >>> > >> >>> > >> >>> The pi doesn't seem to have any general counter/timer hardware, like > >> >>> ARMs usually do. I've seen vague references to using the GPU to do > >> >>> timings. > >> >>> > >> >>> I'd like to measure frequencies and timestamp some edges, in the 1 us > >> >>> sort of domain, several channels. I guess we could hang a small FPGA > >> >>> off to the side if pi can't do it. > >> >>> > >> >>> Do pi's have crystal oscillators? I guess we could add one too. > >> >>> > >> >>> > >> >>> > >> >> > >> >>Are you serious about using yet another aliexpress toy for some > >> >>real design? > >> > > >> >https://en.wikipedia.org/wiki/Raspberry_Pi > >> > > >> >Not exactly a toy. But it would save us using up our stock of FPGAs > >> >and ARM chips, and I know a guy who would like to do the programming. > >> >He's a retired Fellow of United Technologies (Collins) who really > >> >likes to code. > >> > > >> > > >> >>Other than the obvious question above, does not ARM have some > >> >>sort of timebase register as part of the core? This might be > >> >>usable to some extent, depending on how much jitter you can > >> >>tolerate. > >> > > >> >The ARM in the pi seems to have none of the usual counter/timer stuff, > >> >so we'd have to do that externally, in a small FPGA probably. We might > >> >have three frequency counters and maybe six edge time stampers in a > >> >FIFO or something. Pretty simple. > >> > > >> Well, we seem to have only two options, a RaspberryPi or an ARM, one > >> being too small and the other being too large. > >> > >> But there is actually a third option that falls between these two > >> options in size, a Microchip AVR microcontroller. Programmed in a > >> dialect of Ansi C, with code in a flash memory and loaded on startup. > >> > >> .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> > > > >in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? > > > >*raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M > Far more I/O stuff, and timers et al. >
most if not all cortex-m have far more horsepower,memory,timers, and IO than an AVR
On Tuesday, 19 July 2022 at 23:18:53 UTC+1, Joe Gwinn wrote:
> On Tue, 19 Jul 2022 14:29:58 -0700 (PDT), Lasse Langwadt Christensen > <lang...@fonz.dk> wrote: > > >tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn: > >> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin > >> <jlarkin@highland_atwork_technology.com> wrote: > >> > >> >On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> > >> >wrote: > >> > > >> >>On 7/18/2022 22:13, John Larkin wrote: > >> >>> > >> >>> > >> >>> The pi doesn't seem to have any general counter/timer hardware, like > >> >>> ARMs usually do. I've seen vague references to using the GPU to do > >> >>> timings. > >> >>> > >> >>> I'd like to measure frequencies and timestamp some edges, in the 1 us > >> >>> sort of domain, several channels. I guess we could hang a small FPGA > >> >>> off to the side if pi can't do it. > >> >>> > >> >>> Do pi's have crystal oscillators? I guess we could add one too. > >> >>> > >> >>> > >> >>> > >> >> > >> >>Are you serious about using yet another aliexpress toy for some > >> >>real design? > >> > > >> >https://en.wikipedia.org/wiki/Raspberry_Pi > >> > > >> >Not exactly a toy. But it would save us using up our stock of FPGAs > >> >and ARM chips, and I know a guy who would like to do the programming. > >> >He's a retired Fellow of United Technologies (Collins) who really > >> >likes to code. > >> > > >> > > >> >>Other than the obvious question above, does not ARM have some > >> >>sort of timebase register as part of the core? This might be > >> >>usable to some extent, depending on how much jitter you can > >> >>tolerate. > >> > > >> >The ARM in the pi seems to have none of the usual counter/timer stuff, > >> >so we'd have to do that externally, in a small FPGA probably. We might > >> >have three frequency counters and maybe six edge time stampers in a > >> >FIFO or something. Pretty simple. > >> > > >> Well, we seem to have only two options, a RaspberryPi or an ARM, one > >> being too small and the other being too large. > >> > >> But there is actually a third option that falls between these two > >> options in size, a Microchip AVR microcontroller. Programmed in a > >> dialect of Ansi C, with code in a flash memory and loaded on startup. > >> > >> .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> > > > >in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? > > > >*raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M > Far more I/O stuff, and timers et al. > > > Joe Gwinn
One interesting thing I noticed about the new AVR series (AVR-DA, AVR-DB, AVR-DD) is that the maximum clock speed dependency on power supply voltage has gone. They have an on-chip power supply regulator and work from 1.8 to 5.5V at a maximum of 24MHz at all voltages in that range. They are being promoted for safety critical applications and have some hardware features to support that together with a certified toolchain. A very simple architecture can have advantages in such domains. It does look as if Microchip have taken the AVR range and enhanced it in some very useful ways that could make these devices a good choice for a new design. John
On Wed, 20 Jul 2022 00:32:25 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>onsdag den 20. juli 2022 kl. 00.18.53 UTC+2 skrev Joe Gwinn: >> On Tue, 19 Jul 2022 14:29:58 -0700 (PDT), Lasse Langwadt Christensen >> <lang...@fonz.dk> wrote: >> >> >tirsdag den 19. juli 2022 kl. 23.22.28 UTC+2 skrev Joe Gwinn: >> >> On Mon, 18 Jul 2022 13:55:37 -0700, John Larkin >> >> <jlarkin@highland_atwork_technology.com> wrote: >> >> >> >> >On Mon, 18 Jul 2022 22:23:21 +0300, Dimiter_Popoff <d...@tgi-sci.com> >> >> >wrote: >> >> > >> >> >>On 7/18/2022 22:13, John Larkin wrote: >> >> >>> >> >> >>> >> >> >>> The pi doesn't seem to have any general counter/timer hardware, like >> >> >>> ARMs usually do. I've seen vague references to using the GPU to do >> >> >>> timings. >> >> >>> >> >> >>> I'd like to measure frequencies and timestamp some edges, in the 1 us >> >> >>> sort of domain, several channels. I guess we could hang a small FPGA >> >> >>> off to the side if pi can't do it. >> >> >>> >> >> >>> Do pi's have crystal oscillators? I guess we could add one too. >> >> >>> >> >> >>> >> >> >>> >> >> >> >> >> >>Are you serious about using yet another aliexpress toy for some >> >> >>real design? >> >> > >> >> >https://en.wikipedia.org/wiki/Raspberry_Pi >> >> > >> >> >Not exactly a toy. But it would save us using up our stock of FPGAs >> >> >and ARM chips, and I know a guy who would like to do the programming. >> >> >He's a retired Fellow of United Technologies (Collins) who really >> >> >likes to code. >> >> > >> >> > >> >> >>Other than the obvious question above, does not ARM have some >> >> >>sort of timebase register as part of the core? This might be >> >> >>usable to some extent, depending on how much jitter you can >> >> >>tolerate. >> >> > >> >> >The ARM in the pi seems to have none of the usual counter/timer stuff, >> >> >so we'd have to do that externally, in a small FPGA probably. We might >> >> >have three frequency counters and maybe six edge time stampers in a >> >> >FIFO or something. Pretty simple. >> >> > >> >> Well, we seem to have only two options, a RaspberryPi or an ARM, one >> >> being too small and the other being too large. >> >> >> >> But there is actually a third option that falls between these two >> >> options in size, a Microchip AVR microcontroller. Programmed in a >> >> dialect of Ansi C, with code in a flash memory and loaded on startup. >> >> >> >> .<https://www.microchip.com/en-us/products/microcontrollers-and-microprocessors/8-bit-mcus/avr-mcus> >> > >> >in what world does an ancient 8 bit AVR fall between RaspberryPi and ARM* ? >> > >> >*raspberry pi is also ARM, it is just a Cortex-A CPU, the smaller MCUs are Cortex-M >> Far more I/O stuff, and timers et al. >> > >most if not all cortex-m have far more horsepower,memory,timers, and IO than an AVR >
Yes, most likely. My point being that we were bouncing between the guard-rails (too big, too small), and needed to widen our ken. If I recall, the AVR does not need any VHDL or external FPGAs. Joe Gwinn