Picomite

[Jeff_T]

I am getting close to trying basic on a pi pico, I was looking for a ready made picomite vga board to try some retro computing. This video was interesting and their board is just $12, I would find it hard to build one for less than that price

https://www.tindie.com/products/land_boards/raspberry-pi-pico-card-with-vga-sound-keyboard/

Are there any thoughts on this or a link to any alternatives.

[granz]

I have had my eye on that for quite a while. Land Boards seems like a pretty cool company (and that is one of my favorite products from them.)

There is another version of that board; version 2 (https://www.tindie.com/products/land_boards/raspberry-pi-pico-card-with-vga-sound-kbd-ver-2/) that costs the same (note that the $12 is only for the bare board - you will need to pay for everything else) but has more external GPIO (from the MCP23017 Port Expanders.) Actually, the assembled price ($60) is pretty good, unless you have a very well stocked parts bin. Also, consider replacing the Pico with the Pico 2W - that is what I am doing with my PicoCalc.

Also, apparently some of the newer MCP23017s do not have all of their IO pins available for input (https://electronics.stackexchange.com/questions/661173/output-only-io-expander-question).

If you just want to try PicoMite BASIC, you can just put a Pico onto a breadboard, then load that BASIC onto the Pico and get a feel for the BASIC via the USB serial link (use minicom if using Linux, or Tera Term if you use Windows.) This will let you get familiar with the system, and is still a lot of fun. But, I still recommend a full system like that Land Board system that you found.

[Jeff_T]

Thanks for the correction and feedback @granz , I have a bad habit of skimming the details sometimes. Still worth considering even the V 03 board is appealing.

I will definitely begin with a bare system connected over USB but I have a monitor just begging for a vga connected device  😁

[granz]

Thanks for the correction and feedback @granz , I have a bad habit of skimming the details sometimes. Still worth considering even the V 03 board is appealing.

Yeah, like I said, that Land Boards seems to be pretty good. I also just found out that they are in Connelsville, which is pretty close to me. I will try to get in touch with them and invite them to our meetup - although, then I may go broke, buying their stuff. 

I will definitely begin with a bare system connected over USB but I have a monitor just begging for a vga connected device  😁

Like I said, just plugging a Pico into a breadboard, and loading the PicoMite .UF2 firmware file, gives you a working system.


This is pretty much my first working with a Pico - except that I used a Pico, rather than this Pico 2W.

Even without the super cap, it works pretty well. How are you for the basic components? If you want, I can send you a couple of my old component packs.

[Jeff_T]

@granz 

although, then I may go broke, buying their stuff

that is too funny but I know the feeling.

I can send you a couple of my old component packs.

that is a kind offer, I don't keep a lot of parts laying around I just buy as needed and I am not sure where I am going next 

I read about a meet up in another post and I think it will be a lot of fun but I can't see it happening with me, this year anyway. I'm in TN btw.

I'll keep posting on the pico and basic stuff.

[JKnightandKARR]

Ok, need help..... Playing with the Picomite on the Pico Breadboard Kit Plus Verion tonight, and I keep getting this:

Code Select Expand

[7] Option AUDIO 17, 0
Error : Invalid in a program
I've been up n down all the manuals for Picomite and the MMBasic ones, I can NOT find what's wrong... Whole code below, any help appreciated.

Code Select Expand

SetPin GP12, DOUT
SetPin GP13, DOUT
Dim a%=(RGB(Red))
Dim b%=(RGB(Green))
Dim c%=(RGB(Blue))
OPTION AUDIO GP13, GP13

Do
  'Option Audio GP13, GP13
  Device WS2812 O, GP12, 1, &Hff0000
  Pause 500
  Play TONE 697, 1209, 500
  Device WS2812 O, GP12, 1, &Hffff00
  Pause 500
  Play TONE 770, 1336, 500
  Device WS2812 O, GP12, 1, &H00ff00
  Pause 500
  Play TONE 852, 1477, 500
  Device WS2812 O, GP12, 1, &H00ffff
  Pause 500
  Play TONE 941, 1336, 500
LoopAll I've done to the previous code was add the stuff to try n play the tones, which is pin GP13 on the board, the previous code, just to flash diff LED colors on the built in RGB LED, which works, but as far as the audio, NO IDEA what's wrong... I've commented out Option and it says, "Audio not enabled". Current ver of the system btw. Thanks.

[granz]

Ok, need help..... Playing with the Picomite on the Pico Breadboard Kit Plus Verion tonight

Is this the board that you are using?

, and I keep getting this:

Code Select Expand

[7] Option AUDIO 17, 0
Error : Invalid in a program

That won't work for your board (if it is the one above.) Pin 17 (GP13) is for the speaker, but there is no pin 0. As the manual says, it is best to stick with the GPxx nomenclature, rather than the pin number.

I've been up n down all the manuals for Picomite and the MMBasic ones, I can NOT find what's wrong... Whole code below, any help appreciated.

Code Select Expand

SetPin GP12, DOUT
SetPin GP13, DOUT
Dim a%=(RGB(Red))
Dim b%=(RGB(Green))
Dim c%=(RGB(Blue))
OPTION AUDIO GP13, GP13

Do
  'Option Audio GP13, GP13
  Device WS2812 O, GP12, 1, &Hff0000
  Pause 500
  Play TONE 697, 1209, 500
  Device WS2812 O, GP12, 1, &Hffff00
  Pause 500
  Play TONE 770, 1336, 500
  Device WS2812 O, GP12, 1, &H00ff00
  Pause 500
  Play TONE 852, 1477, 500
  Device WS2812 O, GP12, 1, &H00ffff
  Pause 500
  Play TONE 941, 1336, 500
LoopAll I've done to the previous code was add the stuff to try n play the tones, which is pin GP13 on the board, the previous code, just to flash diff LED colors on the built in RGB LED, which works, but as far as the audio, NO IDEA what's wrong... I've commented out Option and it says, "Audio not enabled". Current ver of the system btw. Thanks.

Sound from the PicoMite can be a bit complicated.

If you take a look at the OPTION AUDIO command (pg 48 of the 6.01.00 manual) you are to define the A and the B channels (or the left and the right channels) of a single PWM port. On page 16, of the above version manual, you can see (on the outer-most labels, in brown) the PWM ports. You may use GP0 with, and only with GP1 for PWM 1. For your board, you can use GP13 for the right channel, but only with GP12, for the left channel.

In your Option Audio GP13, GP13 you are trying to make GP13 both the left, and the right sound channels.

Try using OPTION AUDIO GP12, GP13 and then when you want to make sound, use Play TONE 0, 1336, 500 specifying only a frequency for the right channel (channel B.) Now, that may/will cause some troubles with the WS2812 LED, since that is tied to GP12. It seems that, with that particular board, you may use either the speaker, or the WS2812, but not both at the same time.

I have seen similar design "errors" in other boards. That is one thing that I don't really care for with the Pico - not the Pico itself, but designers who ignore the pin restrictions of the PicoMite implementation of the Raspberry Pi Pico chip. PicoMite BASIC is a fantastic development environment, but some limitations make it more difficult to use - and I don't know if it is the language (from the little that I have seen, MicroPython does not have these restrictions) or the designs using the Pico chip ignoring PicoMite limitations.

[JKnightandKARR]

Ok, need help..... Playing with the Picomite on the Pico Breadboard Kit Plus Verion tonight

Is this the board that you are using?

Yes, that's the board.

, and I keep getting this:

Code Select Expand

[7] Option AUDIO 17, 0
Error : Invalid in a program

That won't work for your board (if it is the one above.) Pin 17 (GP13) is for the speaker, but there is no pin 0. As the manual says, it is best to stick with the GPxx nomenclature, rather than the pin number.

According to the manual(s), setting the OPTION AUDIO PG13, 0, which I also tried, 0 sets the 2nd pin to disable, but I also removed it and just had OPTION AUDIO GP!3, all yield the same error message.

I've been up n down all the manuals for Picomite and the MMBasic ones, I can NOT find what's wrong... Whole code below, any help appreciated.

Code Select Expand

SetPin GP12, DOUT
SetPin GP13, DOUT
Dim a%=(RGB(Red))
Dim b%=(RGB(Green))
Dim c%=(RGB(Blue))
OPTION AUDIO GP13, GP13

Do
  'Option Audio GP13, GP13
  Device WS2812 O, GP12, 1, &Hff0000
  Pause 500
  Play TONE 697, 1209, 500
  Device WS2812 O, GP12, 1, &Hffff00
  Pause 500
  Play TONE 770, 1336, 500
  Device WS2812 O, GP12, 1, &H00ff00
  Pause 500
  Play TONE 852, 1477, 500
  Device WS2812 O, GP12, 1, &H00ffff
  Pause 500
  Play TONE 941, 1336, 500
LoopAll I've done to the previous code was add the stuff to try n play the tones, which is pin GP13 on the board, the previous code, just to flash diff LED colors on the built in RGB LED, which works, but as far as the audio, NO IDEA what's wrong... I've commented out Option and it says, "Audio not enabled". Current ver of the system btw. Thanks.

Sound from the PicoMite can be a bit complicated.

If you take a look at the OPTION AUDIO command (pg 48 of the 6.01.00 manual) you are to define the A and the B channels (or the left and the right channels) of a single PWM port. On page 16, of the above version manual, you can see (on the outer-most labels, in brown) the PWM ports. You may use GP0 with, and only with GP1 for PWM 1. For your board, you can use GP13 for the right channel, but only with GP12, for the left channel.

In your Option Audio GP13, GP13 you are trying to make GP13 both the left, and the right sound channels.

Try using OPTION AUDIO GP12, GP13 and then when you want to make sound, use Play TONE 0, 1336, 500 specifying only a frequency for the right channel (channel B.) Now, that may/will cause some troubles with the WS2812 LED, since that is tied to GP12. It seems that, with that particular board, you may use either the speaker, or the WS2812, but not both at the same time.

I have seen similar design "errors" in other boards. That is one thing that I don't really care for with the Pico - not the Pico itself, but designers who ignore the pin restrictions of the PicoMite implementation of the Raspberry Pi Pico chip. PicoMite BASIC is a fantastic development environment, but some limitations make it more difficult to use - and I don't know if it is the language (from the little that I have seen, MicroPython does not have these restrictions) or the designs using the Pico chip ignoring PicoMite limitations.

Ok, I can try that.  Why would they make restrictions, I wonder?? So it's the Picomite firmware that has these restrictions??  I can always consider MicroPython an option, I guess. 

EDIT:I made the mods as you suggested. SAME error still.... Even tried it with GP0 & GP1... no change...

[granz]

According to the manual(s), setting the OPTION AUDIO PG13, 0, which I also tried, 0 sets the 2nd pin to disable, but I also removed it and just had OPTION AUDIO GP!3, all yield the same error message.

Where did you find that in the manual? The only thing that I can find about disabling audio is on page 99, in the 6.00.00 manual, where it talks about OPTION AUDIO DISABLE, but that is to disable audio entirely.

Ok, I can try that.  Why would they make restrictions, I wonder?? So it's the Picomite firmware that has these restrictions??  I can always consider MicroPython an option, I guess. 

I don't know that it is so much a PicoMite BASIC restriction, as fitting more in line with the hardware. The Raspberry Pi Foundation designed the Pico with the matching PWM channels, and PicoMite BASIC just follows that design. Like I said, I'm not overly familiar with Python (Micro-, or Circuit-) and do not know if they use special tricks to get around that, or...?

[JKnightandKARR]

Did you see where I posted the changes you mentioned didn't work?

According to the manual(s), setting the OPTION AUDIO PG13, 0, which I also tried, 0 sets the 2nd pin to disable, but I also removed it and just had OPTION AUDIO GP!3, all yield the same error message.

Where did you find that in the manual? The only thing that I can find about disabling audio is on page 99, in the 6.00.00 manual, where it talks about OPTION AUDIO DISABLE, but that is to disable audio entirely.

Ok, I can try that.  Why would they make restrictions, I wonder?? So it's the Picomite firmware that has these restrictions??  I can always consider MicroPython an option, I guess. 

I don't know that it is so much a PicoMite BASIC restriction, as fitting more in line with the hardware. The Raspberry Pi Foundation designed the Pico with the matching PWM channels, and PicoMite BASIC just follows that design. Like I said, I'm not overly familiar with Python (Micro-, or Circuit-) and do not know if they use special tricks to get around that, or...?

It's mentioned here https://geoffg.net/WindowsMMBasic.html
but they are on this page: https://mmbasic.com/ 
Here is the language manual: https://mmbasic.com/Download/MMBasic%20Language%20Manual.pdf
and the other manual I found: https://mmbasic.com/Download/MMBasic%20DOS%20Version%20Manual.pdf
General downloads: https://mmbasic.com/downloads.html

[JKnightandKARR]

Solution below:
https://yamavu.github.io/PicoMite_User_Manual/options_audio.html
I FINALLY found the issue.... One I didn't see in the documentation or is not there..... anyhow solution is:

Option Audio GP##, GP##

is run on the command prompt NOT in the program..... once set it apparently remains set, even if power is removed, to remove it, type Option Audio Disable.  Now I gotta see if the pins are 5v or 3.3v and create a speaker circuit to use with this....

[granz]

Solution below:
https://yamavu.github.io/PicoMite_User_Manual/options_audio.html
I FINALLY found the issue.... One I didn't see in the documentation or is not there..... anyhow solution is:

Option Audio GP##, GP##

is run on the command prompt NOT in the program..... once set it apparently remains set, even if power is removed, to remove it, type Option Audio Disable.  Now I gotta see if the pins are 5v or 3.3v and create a speaker circuit to use with this....

So, are you able to use the single GP13, or do you need to use both channels in the one OPTION command?

[JKnightandKARR]

Solution below:
https://yamavu.github.io/PicoMite_User_Manual/options_audio.html
I FINALLY found the issue.... One I didn't see in the documentation or is not there..... anyhow solution is:

Option Audio GP##, GP##

is run on the command prompt NOT in the program..... once set it apparently remains set, even if power is removed, to remove it, type Option Audio Disable.  Now I gotta see if the pins are 5v or 3.3v and create a speaker circuit to use with this....

So, are you able to use the single GP13, or do you need to use both channels in the one OPTION command?

I can try that. Setting PWMA to 0 should disable that pin

[JKnightandKARR]

So, are you able to use the single GP13, or do you need to use both channels in the one OPTION command?

Well, have a discovery, setting Option Audio PWM-A, PWM-B to anything other then something like Option Audio GP12, GP13 won't work, so stuff like Option Audio 0, GP13 or Option Audio GP13, 0 will NOT work. Ok, I did notice that there is added constant noise that starts when setting the audio up, and this is before I even get to Play Tone ##, ##, duration.  Maybe need to use the filter on Pg 35 of the manual...

@Chris Savage
I've got links to the PPDB and PDB, now I measured the Raspberry Pi Pico and got 3.3v on the output, now what I need is, how can I modify the audio amp on the PDB to work better on 3.3v , not to mention putting the 2 audio ch into 1 ch or should I try the circuit on the PPDB even though I am using an ext speaker? The Picomite manual, on pg 35 shows a low-passfilter, that shouldn't be an issue using SMD right off the pins, but its the amplifier I'll need some help with.

https://forums.parallax.com/uploads/FileUpload/53/fd27a771f96245b341cff1c4eb02e5.pdf
https://forums.parallax.com/uploads/FileUpload/d1/6d174a41da887b2bbe09ce860bed6c.pdf

Picomite manual:
https://geoffg.net/Downloads/picomite/PicoMite_User_Manual.pdf

[Chris Savage]

I've got links to the PPDB and PDB, now I measured the Raspberry Pi Pico and got 3.3v on the output, now what I need is, how can I modify the audio amp on the PDB to work better on 3.3v , not to mention putting the 2 audio ch into 1 ch or should I try the circuit on the PPDB even though I am using an ext speaker? The Picomite manual, on pg 35 shows a low-passfilter, that shouldn't be an issue using SMD right off the pins, but its the amplifier I'll need some help with.

Well, the amplifier on the PPDB is stereo. It is designed to use headphones.

I didn't find any filter circuit on page 35. In your last link, I did find one on page 49, for which the output could be connected to external stereo amplifier speaker systems, such as computer speakers, which can be obtained cheap, like these.