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robert.rozee
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Joined: 31/12/2012
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Posted: 03:51pm 23 Dec 2023

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Mixtel90 said Just bear in mind that the PicoMite VGA uses a memory mapped display that is sent out to the video by the second CPU. There is virtually no load on the primary CPU. As such the speed of the display is very fast. Even USB is a serial interface and, as such, has to introduce delays. You won't be able to get the same display speed, just as you wouldn't if it was a serial terminal

am just a tad confused by your comment: from the perspective of the VGA picomite all it sees as 'different' is that no PS/2 keyboard or mouse is attached, instead all input is coming from what appears to be a PC host running a terminal emulator. VGA and mmbasic are still hosted on single pico. but, in fact, that PC host is replaced by a ps2x2pico+CDC and small USB hub.

construction-wise, it would be a PCB holding 2 picos, a GL850G USB hub chip (https://www.ebay.com/itm/134741475712 ) worth about $1.50, 2x USB sockets, and 4x 8mm pogo pins (to make contact with D+ and D- pads on both picos). plus, of course, the VGA connector.

left out is the 5v/3v level translators for the PS/2 interface(s).

to date, this seems to be one of the simplest (and cheap) solutions.

cheers,
rob :-)

Mixtel90

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Posted: 04:28pm 23 Dec 2023

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You may as well just use tera term and a PicoMite VGA then. :)

The Pico may be running the program but it can't read thee mouse or react to it. There are too many interrupts. Peter has been through this before.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
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ebbandflow
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Joined: 31/08/2023
Location: United States
Posts: 19

Posted: 04:32pm 23 Dec 2023

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Awesome find in the ps2x2pico! Here's what I'm going to try for adding a USB keyboard... I figure the level shifting is pointless when communicating from pico to pico. Also going to desolder and reverse the schottky diode to prevent power backfeeding the picomite. Thoughts?
Edited 2023-12-24 02:40 by ebbandflow

robert.rozee
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Posted: 04:40pm 23 Dec 2023

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Mixtel90 said You may as well just use tera term and a PicoMite VGA then

teraterm (et al) implies the pico is tethered to a PC. is the discussion not about using a picomite VGA without it having to be tethered to anything beyond keyboard/mouse/monitor?

Mixtel90 said The Pico may be running the program but it can't read thee mouse or react to it. There are too many interrupts. Peter has been through this before

i thought the picomite VGA supported a mouse? nonetheless, ps2x2pico eliminates those overheads from being the picomite's problem... escape sequences exist to turn mouse reporting on/off as required, and when turned on mouse button and position data is sent in the same way as function key codes, etc.

cheers,
rob :-)
Edited 2023-12-24 02:43 by robert.rozee

Mixtel90

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Posted: 05:30pm 23 Dec 2023

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>>confused<<
That diode is forward from the USB input (VBUS) to VSYS. It's there to protect the PC. Reversing it is to allow VSYS to power the USB keyboard, not to protect anything. If you want to power a USB device from a Pico then power the Pico via VBUS rather than VSYS.

Alternatively, you can simply link VSYS and VBUS when the USB port *isn't* connected to a host.

I don't think any of the MMBasic platforms (except maybe MMB4W) handle a mouse. The CMM2 needs a USB chip to do it.

.
Edited 2023-12-24 03:40 by Mixtel90

Mick

Zilog Inside! nascom.info for Nascom & Gemini
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matherp
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Joined: 11/12/2012
Location: United Kingdom
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Posted: 06:03pm 23 Dec 2023

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CMM2 fully supports either a PS2 mouse (direct) or a USB mouse using an extra Hobbytronics I/F chip

ebbandflow
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Joined: 31/08/2023
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Posted: 06:32pm 23 Dec 2023

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Mixtel90 said That diode is forward from the USB input (VBUS) to VSYS. It's there to protect the PC. Reversing it is to allow VSYS to power the USB keyboard, not to protect anything. If you want to power a USB device from a Pico then power the Pico via VBUS rather than VSYS.

My intent is to prevent the picomite from booting if a powered device is accidently plugged into the keyboard USB port on the ps2X2pico.

Reversing the diode on the ps2x2pico board ensures that the system can not be powered via the 'dedicated keyboard USB port', that it will only supply system power to the keyboard not vice versa. That's what I'm thinking anyway! Testing and quite possibly magic smoke shall decide! xD

stanleyella

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Joined: 25/06/2022
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Posted: 07:42pm 23 Dec 2023

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I only use picomite and thought usb keyboards/and controller pads so cheap, can't use though.
cheap wireless tiny kb and pad.. with laser pointer??
with 7" monitor.. would be nice.

Hans

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Joined: 18/10/2022
Location: Canada
Posts: 116

Posted: 08:44pm 23 Dec 2023

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Mixtel90 said AFAIK they are just pin-pin connectors. A lot of USB keyboards (especially the older ones) will also work with PS2 inputs using one of those.

Those are the adapters you keep in a drawer for ten years, throw away then need one urgently.

You got that right!!!

Hans ....

stanleyella

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Joined: 25/06/2022
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Posted: 09:27pm 23 Dec 2023

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I dug this kb from many "in a drawer 10 years", cut of ps2 plug,works at 3.3 V but too big.
I meant desk space. I don't use the kb mostly.

Edited 2023-12-24 07:52 by stanleyella

Turbo46

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Joined: 24/12/2017
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Posted: 11:37pm 23 Dec 2023

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Quote CMM2 fully supports either a PS2 mouse (direct) or a USB mouse using an extra Hobbytronics I/F chip

Yes, sadly the Picomite VGA will never be a CMM2. A CMM1.5 maybe. I have used the SC USB mouse to serial converter successfully with the CMM1 so surely it can be done with the Picomite VGA?

As I posted above, SC has retrofitted a board based on this GITHUB project (but modified the software) into Geoff's Picomite VGA boot-to-BASIC computer. Strangely, maybe for simplicity of construction, they left the level shifters in on both boards.

I have not read the complete article yet.

Bill

Keep safe. Live long and prosper.

TassyJim

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Joined: 07/08/2011
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Posts: 6098

Posted: 02:30am 24 Dec 2023

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My "PS2 mouse to Wii Classic (and serial) controller" which runs on a nano should be a simple fit to the picoVGA.

The Microsoft Basic Optical mouse (which does USB and PS2) is still listed as currently available for lots of places.

Jim

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thwill

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Joined: 16/09/2019
Location: United Kingdom
Posts: 4040

Posted: 04:00pm 24 Dec 2023

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bigmik said I don’t know much about GitHub, in fact I usually find it very confusing but what does the file. “.gitignore” do or mean?

Hi Mick,

A git repository maps to a directory structure on your local disk. Any file within that directory structure is considered a candidate for source-control by the git tools. You use the .gitignore file to tell the git tools to ignore certain files, e.g. binaries, object files, build directories, temporary files, backups, etc.

e.g. from my Lazer Cycle repository: https://github.com/thwill1000/mmbasic-lazer-cycle/blob/main/.gitignore

# Ignore backup files
*.bak

# Ignore temporary files
*.tmp

So if my local copy of the repository contains any files with .bak or .tmp extensions the git tools won't tell me they aren't under source control or suggest I check them in.

Best wishes,

Tom
Edited 2023-12-25 02:01 by thwill

Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

ebbandflow
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Joined: 31/08/2023
Location: United States
Posts: 19

Posted: 05:27pm 24 Dec 2023

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Well, I have a USB keyboard > ps2x2pico > picomite running on my desk and I'm quite pleased!

I downloaded and flashed the ps2x2pico as outlined here: https://github.com/No0ne/ps2x2pico#usage but I wired it up as shown below. Now that it's working I plan to experiment with reversing the diode (per my previous post) and joining vsys of the picos together instead of vbus.

Edited 2023-12-25 03:28 by ebbandflow

ebbandflow
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Posted: 07:32pm 24 Dec 2023

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Minor setback... the USB keyboard does not seem to reconnect after a power cycle unless the ps2x2pico is reset via the run pin. I think I'll need to reset the ps2x2pico on boot using a spare pin on the picomite or maybe just build an auto reset circuit.

stanleyella

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Joined: 25/06/2022
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Posted: 07:58pm 24 Dec 2023

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@ebbandflow, interesting, not flashed the uft dual yet and didn't know if the shottky diode in the manual ws inbuilt or you added. I don't want to desolder surface anything.
For picomite, what's a mouse for?
https://www.amazon.com/dp/B0859Y3DXX/ref=sspa_dk_detail_1?
edit would the wireless kb in photo or similar work with 2 rpi as £3 for rpipico and it's valid converter. any more info please?
Edited 2023-12-25 07:01 by stanleyella

Mixtel90

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Posted: 08:46pm 24 Dec 2023

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The Schottky diode is built in. There's a diagram showing the Pico's power arrangement r the beginning of the manual.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Posted: 09:07pm 24 Dec 2023

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Mixtel90 said The Schottky diode is built in. There's a diagram showing the Pico's power arrangement r the beginning of the manual.

I always thought you added it. I run some picomites fro 3.3 lin regs for noise reduction but you can live with the switching supply imho.

Mixtel90

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Posted: 10:16pm 24 Dec 2023

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The diode is there because you can damage the USB ports of some PCs if the PC is powered off while there is still a supply on the USB input. VBUS is connected directly to the USB 5V on the Pico and the diode comes off that to feed VSYS, which thn feeds the input of the switching reg. By powering the Pico from VSYS the USB on the PC is protected.

The clone Pico boards don't always have the same system. If you are going to use one then it's important to check its power circuit.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Posted: 12:06am 25 Dec 2023

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not intuitive if you have to add the components or not.

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