• Forth for Arduino Mega

    From Lorem Ipsum@21:1/5 to All on Mon Mar 27 15:36:41 2023
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.

    If I am looking for minimal start up time, would FlashForth be recommended?

    The others I've seen seem rather non-standard and even odd. I don't have time to figure out new stuff. I have a very simple project I need to get running.

    --

    Rick C.

    - Get 1,000 miles of free Supercharging
    - Tesla referral code - https://ts.la/richard11209

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  • From dxforth@21:1/5 to Lorem Ipsum on Tue Mar 28 10:37:03 2023
    On 28/03/2023 9:36 am, Lorem Ipsum wrote:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.

    If I am looking for minimal start up time, would FlashForth be recommended?

    The others I've seen seem rather non-standard and even odd. I don't have time to figure out new stuff. I have a very simple project I need to get running.

    FlashForth isn't bad. The Mega will give you approx 43K of free flash to play with compared to 23K for the UNO. Should be easy to pick up as @ ! etc works on flash, ram. Biggest culture shock I found was FOR NEXT as opposed to DO LOOP.
    Also FlashForth won't let you re-use the same name, requiring one to erase before
    re-loading (e.g. using a MARKER word). I've been working on a fork that's a bit
    more normal in that respect.

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  • From Lorem Ipsum@21:1/5 to dxforth on Mon Mar 27 18:21:37 2023
    On Monday, March 27, 2023 at 7:37:07 PM UTC-4, dxforth wrote:
    On 28/03/2023 9:36 am, Lorem Ipsum wrote:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.

    If I am looking for minimal start up time, would FlashForth be recommended?

    The others I've seen seem rather non-standard and even odd. I don't have time to figure out new stuff. I have a very simple project I need to get running.
    FlashForth isn't bad. The Mega will give you approx 43K of free flash to play
    with compared to 23K for the UNO. Should be easy to pick up as @ ! etc works on flash, ram. Biggest culture shock I found was FOR NEXT as opposed to DO LOOP.
    Also FlashForth won't let you re-use the same name, requiring one to erase before
    re-loading (e.g. using a MARKER word). I've been working on a fork that's a bit
    more normal in that respect.

    Oh, that sucks, the reuse thing. I was looking at parsing the input with the Forth interpreter. That would require using # as a new word. Any code using # inside <# #> could be early in the program, and # defined later. But that won't work I suppose.
    Doesn't really matter. It was just a thought.

    I suppose I could get used to FOR NEXT, but I can't think why that would require no DO LOOP. Let the user decide which to use. I don't recall what the differences are. DO uses a start parameter and a limit. I don't recall what FOR NEXT does. Is the
    conditional at opposite ends of the loop in the two constructs?

    I don't recall what MPE costs. But maybe I should bite the bullet. It's such a tiny job. I guess I could use whatever the Arduino is usually programmed in.

    --

    Rick C.

    + Get 1,000 miles of free Supercharging
    + Tesla referral code - https://ts.la/richard11209

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  • From dxforth@21:1/5 to Lorem Ipsum on Tue Mar 28 13:12:17 2023
    On 28/03/2023 12:21 pm, Lorem Ipsum wrote:
    On Monday, March 27, 2023 at 7:37:07 PM UTC-4, dxforth wrote:
    On 28/03/2023 9:36 am, Lorem Ipsum wrote:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.

    If I am looking for minimal start up time, would FlashForth be recommended? >>>
    The others I've seen seem rather non-standard and even odd. I don't have time to figure out new stuff. I have a very simple project I need to get running.
    FlashForth isn't bad. The Mega will give you approx 43K of free flash to play
    with compared to 23K for the UNO. Should be easy to pick up as @ ! etc works >> on flash, ram. Biggest culture shock I found was FOR NEXT as opposed to DO LOOP.
    Also FlashForth won't let you re-use the same name, requiring one to erase before
    re-loading (e.g. using a MARKER word). I've been working on a fork that's a bit
    more normal in that respect.

    Oh, that sucks, the reuse thing. I was looking at parsing the input with the Forth interpreter. That would require using # as a new word. Any code using # inside <# #> could be early in the program, and # defined later. But that won't work I
    suppose. Doesn't really matter. It was just a thought.

    FWIW here's a link to my fork (called UnoForth to avoid confusion):

    https://drive.google.com/drive/folders/1kh2WcPUc3hQpLcz7TQ-YQiowrozvxfGw

    List of changes from FlashForth is given at the beginning of the source file. Includes hex files for UNO, Mega, Leonardo.

    I suppose I could get used to FOR NEXT, but I can't think why that would require no DO LOOP. Let the user decide which to use. I don't recall what the differences are. DO uses a start parameter and a limit. I don't recall what FOR NEXT does. Is
    the conditional at opposite ends of the loop in the two constructs?

    IIRC DO LOOP exists as a loadable extension. FOR NEXT in FlashForth uses a count. Assuming
    10 then R@ in the loop goes from 9 to 0. If count is zero, the loop is not entered. It's
    the equivalent of eForth's:

    ... FOR AFT ... THEN NEXT ...

    i.e. the AFT THEN is built-in. Conditional is at NEXT and AFT is an unconditional branch
    that's run just once.

    I don't recall what MPE costs. But maybe I should bite the bullet. It's such a tiny job. I guess I could use whatever the Arduino is usually programmed in.
    Forth Inc has SwiftX for AVR. I didn't think MPE made one (?)

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  • From Paul Rubin@21:1/5 to Lorem Ipsum on Mon Mar 27 20:53:03 2023
    Lorem Ipsum <gnuarm.deletethisbit@gmail.com> writes:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR
    CPUs. I did find FlashForth.

    There is also amForth, but if this is for the RS232 converter, at this
    point I wouldn't use an Arduino. It is obsolete imho, and the Mega is
    stupid expensive. You'll have already gotten an email from me about
    what I'd use instead.

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  • From Lorem Ipsum@21:1/5 to Paul Rubin on Mon Mar 27 22:18:22 2023
    On Monday, March 27, 2023 at 11:53:06 PM UTC-4, Paul Rubin wrote:
    Lorem Ipsum <gnuarm.del...@gmail.com> writes:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.
    There is also amForth, but if this is for the RS232 converter, at this
    point I wouldn't use an Arduino. It is obsolete imho, and the Mega is
    stupid expensive. You'll have already gotten an email from me about
    what I'd use instead.

    What do you call "stupid"? I have no idea why you would think the Arduino is "obsolete". I'll look at your email.

    --

    Rick C.

    -+ Get 1,000 miles of free Supercharging
    -+ Tesla referral code - https://ts.la/richard11209

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  • From Lorem Ipsum@21:1/5 to dxforth on Mon Mar 27 22:17:01 2023
    On Monday, March 27, 2023 at 10:12:19 PM UTC-4, dxforth wrote:
    On 28/03/2023 12:21 pm, Lorem Ipsum wrote:
    On Monday, March 27, 2023 at 7:37:07 PM UTC-4, dxforth wrote:
    On 28/03/2023 9:36 am, Lorem Ipsum wrote:
    Unfortunately it looks like there is no Mecrisp for Arduino or the AVR CPUs. I did find FlashForth.

    If I am looking for minimal start up time, would FlashForth be recommended?

    The others I've seen seem rather non-standard and even odd. I don't have time to figure out new stuff. I have a very simple project I need to get running.
    FlashForth isn't bad. The Mega will give you approx 43K of free flash to play
    with compared to 23K for the UNO. Should be easy to pick up as @ ! etc works
    on flash, ram. Biggest culture shock I found was FOR NEXT as opposed to DO LOOP.
    Also FlashForth won't let you re-use the same name, requiring one to erase before
    re-loading (e.g. using a MARKER word). I've been working on a fork that's a bit
    more normal in that respect.

    Oh, that sucks, the reuse thing. I was looking at parsing the input with the Forth interpreter. That would require using # as a new word. Any code using # inside <# #> could be early in the program, and # defined later. But that won't work I suppose.
    Doesn't really matter. It was just a thought.
    FWIW here's a link to my fork (called UnoForth to avoid confusion):

    https://drive.google.com/drive/folders/1kh2WcPUc3hQpLcz7TQ-YQiowrozvxfGw

    List of changes from FlashForth is given at the beginning of the source file.
    Includes hex files for UNO, Mega, Leonardo.
    I suppose I could get used to FOR NEXT, but I can't think why that would require no DO LOOP. Let the user decide which to use. I don't recall what the differences are. DO uses a start parameter and a limit. I don't recall what FOR NEXT does. Is the
    conditional at opposite ends of the loop in the two constructs?
    IIRC DO LOOP exists as a loadable extension. FOR NEXT in FlashForth uses a count. Assuming
    10 then R@ in the loop goes from 9 to 0. If count is zero, the loop is not entered. It's
    the equivalent of eForth's:

    ... FOR AFT ... THEN NEXT ...

    i.e. the AFT THEN is built-in. Conditional is at NEXT and AFT is an unconditional branch
    that's run just once.
    I don't recall what MPE costs. But maybe I should bite the bullet. It's such a tiny job. I guess I could use whatever the Arduino is usually programmed in.
    Forth Inc has SwiftX for AVR. I didn't think MPE made one (?)

    Yes, I just visited the MPE site and they have no AVR forth that I can find. I remember when they didn't support ARMs and I tried to talk Stephen into making one on his dime. At that time, they didn't want to pay for it and were waiting for a customer
    to foot the bill. I tried to explain that ARM was going to be the next big thing. I don't think I convinced him, but maybe I planted the seed. lol

    They seem to be very ARM oriented now.

    I will take a look at Swift Forth. I can't believe I forgot them. Thanks.

    --

    Rick C.

    -- Get 1,000 miles of free Supercharging
    -- Tesla referral code - https://ts.la/richard11209

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  • From Paul Rubin@21:1/5 to Lorem Ipsum on Tue Mar 28 01:43:08 2023
    Lorem Ipsum <gnuarm.deletethisbit@gmail.com> writes:
    What do you call "stupid"? I have no idea why you would think the
    Arduino is "obsolete". I'll look at your email.

    "Stupid expensive" = idiom for something way more expensive than needed
    for this purpose. The Arduino Mega's main feature is a huge number of
    i/o pins. I guess there are some control applications for which it
    isn't obsolete, but for this type of communications app it's a poor fit nowadays. The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board. I have one of the boards on order and have an
    email question pending with the manufacturer, so I'll send you an update
    when something happens. The board should arrive around the end of the
    week.

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  • From Lorem Ipsum@21:1/5 to Paul Rubin on Tue Mar 28 17:35:01 2023
    On Tuesday, March 28, 2023 at 4:43:11 AM UTC-4, Paul Rubin wrote:
    Lorem Ipsum <gnuarm.del...@gmail.com> writes:
    What do you call "stupid"? I have no idea why you would think the
    Arduino is "obsolete". I'll look at your email.
    "Stupid expensive" = idiom for something way more expensive than needed
    for this purpose.

    Yes, I know what it means. Your comment still requires explanation.


    The Arduino Mega's main feature is a huge number of
    i/o pins. I guess there are some control applications for which it
    isn't obsolete, but for this type of communications app it's a poor fit nowadays.

    You have odd ideas of what fits and what doesn't. I don't have maximum requirements, only minimum... well, some are maximum, like price, size, weight. I don't want anything that has to be shipped on a pallet, so the Auduino Mega is fine for this task.
    I have no reason to reject a board on I/O count. What you are thinking, is that it must be expensive, while it is not. Again, I have requirements of price, but the Arduino Mega is well under my limit. No need to optimize that which does not add
    useful value.


    The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board. I have one of the boards on order and have an
    email question pending with the manufacturer, so I'll send you an update when something happens. The board should arrive around the end of the
    week.

    I didn't realize the Pico used the oddball ARM chip, without the usual rPi Linux. That might work ok.

    Please don't assume I am not discussing this with others.

    --

    Rick C.

    +- Get 1,000 miles of free Supercharging
    +- Tesla referral code - https://ts.la/richard11209

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  • From dxforth@21:1/5 to Paul Rubin on Wed Mar 29 14:15:52 2023
    On 28/03/2023 7:43 pm, Paul Rubin wrote:
    ...
    The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board.

    I never considered Pico but googling I found a video of it being used
    with Forth. I gather the chip has 264K ram and 2MB flash which sounds
    plenty. OTOH it doesn't have the add-on boards Arduino is famous for?
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?

    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.
    I assume these are legit - unlike Arduino clones with counterfeit
    ATmega328P ? How hot does the Pico run? I notice some sellers include
    a heatsink!

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  • From none) (albert@21:1/5 to dxforth@gmail.com on Wed Mar 29 12:09:43 2023
    In article <u00ah8$3kei$1@dont-email.me>, dxforth <dxforth@gmail.com> wrote: >On 28/03/2023 7:43 pm, Paul Rubin wrote:
    ...
    The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board.

    I never considered Pico but googling I found a video of it being used
    with Forth. I gather the chip has 264K ram and 2MB flash which sounds >plenty. OTOH it doesn't have the add-on boards Arduino is famous for?
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?

    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.
    I assume these are legit - unlike Arduino clones with counterfeit
    ATmega328P ? How hot does the Pico run? I notice some sellers include
    a heatsink!


    A new development is noforth for the pico boards, to
    be pubished shortly.
    The 10 i/o processors is a bonus. For example I could reserve
    one of those processors to generate a midi signal at the exact
    specs, with buffering and no need for interrupts.

    https://home.hccnet.nl/anij/nof/noforth.html

    This is mature, with dozens of tested projects (click on
    'Egel project') This goes back to the 8051.

    Groetjes Albert
    --
    Don't praise the day before the evening. One swallow doesn't make spring.
    You must not say "hey" before you have crossed the bridge. Don't sell the
    hide of the bear until you shot it. Better one bird in the hand than ten in
    the air. First gain is a cat spinning. - the Wise from Antrim -

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  • From Lorem Ipsum@21:1/5 to none albert on Wed Mar 29 08:29:32 2023
    On Wednesday, March 29, 2023 at 6:09:48 AM UTC-4, none albert wrote:
    In article <u00ah8$3kei$1...@dont-email.me>, dxforth <dxf...@gmail.com> wrote:
    On 28/03/2023 7:43 pm, Paul Rubin wrote:
    ...
    The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board.

    I never considered Pico but googling I found a video of it being used
    with Forth. I gather the chip has 264K ram and 2MB flash which sounds >plenty. OTOH it doesn't have the add-on boards Arduino is famous for?
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?

    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.
    I assume these are legit - unlike Arduino clones with counterfeit >ATmega328P ? How hot does the Pico run? I notice some sellers include
    a heatsink!

    A new development is noforth for the pico boards, to
    be pubished shortly.
    The 10 i/o processors is a bonus. For example I could reserve
    one of those processors to generate a midi signal at the exact
    specs, with buffering and no need for interrupts.

    https://home.hccnet.nl/anij/nof/noforth.html

    This is mature, with dozens of tested projects (click on
    'Egel project') This goes back to the 8051.

    Interesting. I'm not clear on how this is ported to a new board. I suppose all the rPi pico boards will have the same console port. The hardware I would be using with the pico would use pins 1, 2 and 6, 7 for the application UARTs. Can a different
    port be used for the console?

    It's not clear how to get to other pins when the waveshare serial port is attached. This may not be a good mate to this project. The Pico board only seems to have two UARTs. Several places to connect to them, but only two UARTs. Likewise, many pins,
    but only two SPI and two I2C.

    BTW, if you'd like to make your web page more readable, you might not use the colors you are using, or maybe none at all. The grey is hard for me to read, and the orange text is nearly impossible. While colors are pretty, black text on white background
    is much more readable.

    Any idea when noforth for the pico will be out?

    --

    Rick C.

    ++ Get 1,000 miles of free Supercharging
    ++ Tesla referral code - https://ts.la/richard11209

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  • From dxforth@21:1/5 to albert on Thu Mar 30 12:08:11 2023
    On 29/03/2023 9:09 pm, albert wrote:
    In article <u00ah8$3kei$1@dont-email.me>, dxforth <dxforth@gmail.com> wrote:
    On 28/03/2023 7:43 pm, Paul Rubin wrote:
    ...
    The email suggested using a Raspberry Pi Pico with a
    Waveshare RS232 board.

    I never considered Pico but googling I found a video of it being used
    with Forth. I gather the chip has 264K ram and 2MB flash which sounds
    plenty. OTOH it doesn't have the add-on boards Arduino is famous for?
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?

    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.
    I assume these are legit - unlike Arduino clones with counterfeit
    ATmega328P ? How hot does the Pico run? I notice some sellers include
    a heatsink!


    A new development is noforth for the pico boards, to
    be pubished shortly.
    The 10 i/o processors is a bonus. For example I could reserve
    one of those processors to generate a midi signal at the exact
    specs, with buffering and no need for interrupts.

    https://home.hccnet.nl/anij/nof/noforth.html

    This is mature, with dozens of tested projects (click on
    'Egel project') This goes back to the 8051.

    Thanks. Look forward to seeing the article when it's published.
    It's a pity the Pico doesn't come in a form factor similar to Arduino
    which would make it easier to develop with.

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  • From Paul Rubin@21:1/5 to Lorem Ipsum on Wed Mar 29 18:31:26 2023
    Lorem Ipsum <gnuarm.deletethisbit@gmail.com> writes:
    Yes, I know what it means. Your comment still requires explanation.

    The Mega imho is overkill for the application, almost in the same way
    that a mini PC is overkill.
    I didn't realize the Pico used the oddball ARM chip, without the usual
    rPi Linux. That might work ok.

    Please don't assume I am not discussing this with others.

    It's fine, I don't want to send you a proposal to make the gadget until
    I've tested the serial board and am comfortable with the idea of using
    it. It's a $9 board, affordable even for a cave dweller like me, so I
    don't mind having one to play with in any case. With luck I should have
    it tomorrow.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Paul Rubin@21:1/5 to dxforth on Wed Mar 29 18:27:52 2023
    dxforth <dxforth@gmail.com> writes:
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?

    I have the impression that the AVR has better analog stuff but other
    than that I'm not sure. The AVR can run at more voltages. The Pico
    includes a built in DC to DC converter to give the right voltages to its
    RP2040 chip.

    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.

    The bare board is US $4 in the US (plus shipping), and the version with
    header pins pre-soldered is $5. There is another version that has a
    wireless comms chip on board. The wireless chip does wifi and
    bluetooth, but until recently the board was described as wifi-only,
    since software support for bluetooth was not there yet. But, I think
    bluetooth software has started to appear.

    It is computationally a far more powerful board than any version of the
    AVR. It has two ARM 125 MHz Cortex M0+ cores, 264K of ram, and two programmable I/O processors (they are very minimal, like glorified
    PWM's) that can be used for various timing constrained protocols as an alternative to software bit banging.

    I thought I remembered reading that Mecrisp Forth runs on it? It also
    runs Micropython is a more modern interactive programming environment,
    though resource hungry in comparison to Forth. The board has plenty of resources though.

    --- SoupGate-Win32 v1.05
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  • From dxforth@21:1/5 to Paul Rubin on Thu Mar 30 14:08:43 2023
    On 30/03/2023 12:27 pm, Paul Rubin wrote:

    I thought I remembered reading that Mecrisp Forth runs on it? It also
    runs Micropython is a more modern interactive programming environment,
    though resource hungry in comparison to Forth. The board has plenty of resources though.

    Yes - that was the Forth used in the video. The abundance of memory
    and 32-bits is what makes it attractive to develop with. Curious what's involved in rebuilding that forth. I've never stayed with a forth long
    enough that there wasn't something I wanted to change. But then that's
    the nature of Forth, for good or ill.

    --- SoupGate-Win32 v1.05
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  • From Lorem Ipsum@21:1/5 to Paul Rubin on Thu Mar 30 10:25:23 2023
    On Wednesday, March 29, 2023 at 9:31:29 PM UTC-4, Paul Rubin wrote:
    Lorem Ipsum <gnuarm.del...@gmail.com> writes:
    Yes, I know what it means. Your comment still requires explanation.
    The Mega imho is overkill for the application, almost in the same way
    that a mini PC is overkill.

    Ok, but that's a pointless statement. The Arduino Mega meets all the requirements and so is perfectly suitable for the job. I don't know why you can't see this. I think you get fascinated by the toys and have trouble seeing this as an engineering job.
    If I needed a #6 screw to hold something in place, but only have #10 screws, which will work, I use the #10 screws and don't complain about it being "overkill".

    While the miniPC is very much overkill, it's a perfectly acceptable solution if I can meet the price, size and power goals. None of those are well defined, so right now, the miniPC is actually at the head of the list, because it meets all the
    requirements, including being available to buy.


    I didn't realize the Pico used the oddball ARM chip, without the usual
    rPi Linux. That might work ok.

    Please don't assume I am not discussing this with others.
    It's fine, I don't want to send you a proposal to make the gadget until
    I've tested the serial board and am comfortable with the idea of using
    it. It's a $9 board, affordable even for a cave dweller like me, so I
    don't mind having one to play with in any case. With luck I should have
    it tomorrow.

    Good luck.

    --

    Rick C.

    --- Get 1,000 miles of free Supercharging
    --- Tesla referral code - https://ts.la/richard11209

    --- SoupGate-Win32 v1.05
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  • From Travis Bemann@21:1/5 to Paul Rubin on Mon Apr 3 20:16:58 2023
    On Wednesday, March 29, 2023 at 8:27:55 PM UTC-5, Paul Rubin wrote:
    dxforth <dxf...@gmail.com> writes:
    Also not sure how the on-chip peripherals compare with AVR. Can you
    give a summary?
    I have the impression that the AVR has better analog stuff but other
    than that I'm not sure. The AVR can run at more voltages. The Pico
    includes a built in DC to DC converter to give the right voltages to its RP2040 chip.
    Locally Pico boards sell for $AU15 inc. post which is dirt cheap.
    The bare board is US $4 in the US (plus shipping), and the version with header pins pre-soldered is $5. There is another version that has a
    wireless comms chip on board. The wireless chip does wifi and
    bluetooth, but until recently the board was described as wifi-only,
    since software support for bluetooth was not there yet. But, I think bluetooth software has started to appear.

    It is computationally a far more powerful board than any version of the
    AVR. It has two ARM 125 MHz Cortex M0+ cores, 264K of ram, and two programmable I/O processors (they are very minimal, like glorified
    PWM's) that can be used for various timing constrained protocols as an alternative to software bit banging.

    I thought I remembered reading that Mecrisp Forth runs on it? It also
    runs Micropython is a more modern interactive programming environment, though resource hungry in comparison to Forth. The board has plenty of resources though.

    My zeptoforth also fully supports the Raspberry Pi Pico and at least partially supports other RP2040-based boards (with some caveats - I have encountered boards with GigaDevices flash which, while strictly-speaking compatible with zeptoforth, provide poor flash-writing performance, and on boards other than the Pico things such as LED's are not necessarily fully supported or require compiling a "platform" constant to tell zeptoforth which board is in use). It provides full preemptive multitasking with SMP support and supports most of
    the hardware on the Pico with the notable exception of USB (even though I
    plan on changing this in the near future). It is fully-featured out of the box, and also comes with code for things such as controlling displays that can be loaded by the user.

    As for comparing and contrasting Mecrisp-Stellaris and zeptoforth, I must
    admit that Matthias Koch is a compiler wizard and I envy his register-assigning compiler (zeptoforth is also an inlining native code compiler, but does not exude so much compiler-fu). Also, Mecrisp-Stellaris on the RP2040 executes solely out of RAM, while zeptoforth on the RP2040 makes major use of XIP
    mode to execute out of a RAM cache for the external Quad SPI flash (even
    though the zeptoforth kernel is copied into RAM); this enables zeptoforth to execute with larger codebases but makes Mecrisp-Stellaris faster because it does not have to contend with XIP cache misses. Note that both zeptoforth
    and Mecrisp-Stellaris can compile to RAM in addition to flash, in the case of zeptoforth and Mecrisp-Stellaris on platforms other than the RP2040, or
    flash mirrored into RAM, in the case of Mecrisp-Stellaris on the RP2040. In general, Mecrisp-Stellaris is more suited to smaller systems than zeptoforth, since it has a smaller kernel and is not as reliant on a large library of code outside its kernel. This is why zeptoforth will never support STM32F0 MCU's
    and most likely will never support STM32F1 MCU's (even though it could
    possibly support some larger Chinese clones of the STM32F103 which
    provide more flash than the original STM32F103 in the future).

    As for some notes about hardware support for zeptoforth on RP2040-based
    boards:

    WiFi support on the Pico W is specifically not supported, because a CYW43 driver for it has not been written, and may never be written due to licensing issues with Damien George's CYW43 driver (which includes necessary binary blobs). Even if I ever do write a CYW43 driver, it will most likely have to be under Damien George's onerous licensing terms, separate from the rest of zeptoforth in a different repository (and left to the user to compile/load on their own).

    There is a limited WiFi driver for the Wio RP2040, but the ESP8285's WiFi radio on the Wio RP2040 is so unreliable that I simply cannot say that I support it. If it were not for that I spent over a month trying to get the thing to work and
    do not want to consider that effort completely wasted, I would simply delete
    my WiFi driver for it. Note that this WiFi driver has to be manually loaded by the user. Also note that if you do try to use this driver, it gets very poor performance and closing connections is completely broken thanks to a major firmware bug ─ attempting to close a connection will cause the ESP8285 to crash and become unresponsive until its watchdog reboots it, losing any
    state it had before.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)