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Friet
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Joined: 16/12/2020
Location: Belgium
Posts: 13

Posted: 03:30pm 21 Apr 2021

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Hello,

New here, been lurking around for some time. Not much to say as i was waiting for my very own CMM2 to arrive. Which i received last week (ordered back in December @Micromite. The patience was worth it).

However i cannot seem to get any keyboard to function on it.

- Using the CMM2 via a terminal connection works, of course not for gaming, etc
- I have successfully flashed the firmware to the latest 5.07 beta firmware using a USB A to USB A cable, hence i know the USB port where the keyboard connects to should work.
(but that is then powered through the PC..)

So, there are three remaining possibilities :
- none of my keyboards is compatible (HP Slim Keyboard with dongle ; HP wired KBD KV-0316 ; Microsoft Wireless Keyboard 700 V2 ; Ewent EW3113 , with a dongle)
- USB port does not provide a 5 volt output to power the keyboard.
- My power supply is not powerful enough (i seem to recall some messages on this, but not sure)

Q.: what keyboard brands/types have been tested successfully on the CMM2? (Might be interesting to have some central location where that info is gathered)
Q : Anyone who has had the same issues and solved it , i'd gladly take any help i can get..

EDIT : found one of the old threads about keyboard compatibility. I ordered one of the keyboards mentioned in that thread (Logitech K120) , i'll wait and see if that will work. If not, next diagnostics..

Regards,

Frank
Edited 2021-04-22 02:22 by Friet

CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1427

Posted: 05:11pm 21 Apr 2021

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There is a keyboard list that I've kept up to date in the docs area of myretromax.com:

https://docs.myretromax.com/#

The USB port (on a correctly working board) does provide 5V for the keyboard.

Having a beefy quality power supply is very important. I recommend the Samsung or Apple USB charger modules that provide at the very minimum 500 mA. 1000mA is better.
Edited 2021-04-22 03:14 by CircuitGizmos

Micromites and Maximites! - Beginning Maximite

Friet
Newbie

Joined: 16/12/2020
Location: Belgium
Posts: 13

Posted: 08:58pm 22 Apr 2021

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Thanks for the links, In the meantime the keybaord arrived and tested; but no luck.

Hence i'm suspecting my power supply and ordered a more powerful power supply, with a 2400mA max. output. I have already noticed a few times that "1000mA" rated power supplies don't even come close to that value.

To be able to further diagnose the problem, i also ordered a USB multimeter (didn't even know this existed until i looked for information on how to measure USB current and power.)

I do hope there isn't anything wrong with the USB port..i'm not really proficient with a soldering iron.

CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1427

Posted: 11:13pm 22 Apr 2021

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If you power up with the keyboard plugged in and it doesn't find the keyboard, then try unplugging/replugging the keyboard after it has powered up.

Micromites and Maximites! - Beginning Maximite

epsilon

Senior Member

Joined: 30/07/2020
Location: Belgium
Posts: 255

Posted: 06:17am 23 Apr 2021

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Friet,

If you happen to be in the Antwerp area, I wouldn't mind giving your CMM2 a try, just as a quick cross-check with a known good power supply and keyboard.
Just send me an e-mail if interested. You can find my e-mail address in the members section.

Cheers,
Ruben/Epsilon.

Epsilon CMM2 projects

Friet
Newbie

Joined: 16/12/2020
Location: Belgium
Posts: 13

Posted: 11:24am 23 Apr 2021

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Update : received a new 3A Belkin Power supply. No luck..

I'll now wait for the USB multimeter and see what happens with that.

I'm really starting to fear there is no 5Volt output .. which could indicate a faulty soldering somewhere.. (visual inspection doesn't reveal anything, but i don't have a good magnificaton glass or something like that). Do hope it's not the chip itself..

@Epsilon/Ruben : i might take you up on your offer as a final test. Indeed i am from the Antwerp region (Stabroek)

If that doesn't work, the quest for a local soldering/electronics artist starts..

Cheers,

Frank

matherp
Guru

Joined: 11/12/2012
Location: United Kingdom
Posts: 10310

Posted: 11:52am 23 Apr 2021

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Quote I'm really starting to fear there is no 5Volt output

Easy to test - just plug an optical mouse in and see if the LED lights

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 7937

Posted: 02:03pm 23 Apr 2021

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If it powers ok using an A-A lead then the 5v connection on the keyboard socket is ok. That's connected directly to the internal 5v rail.

When you are powering the keyboard using that socket then you must be using an A-B lead and powering the 5v via the switch. As I discovered, not all A-B leads are what they appear to be and some use slightly damp string as conductors! Try a different A-B lead, as short as you can comfortably manage. A USB meter won't tell you the voltage where you want to know it - at the USB-B socket - and some leads will easily drop a whole volt under load even if your power supply is giving the full 5v.

USB A-B leads are almost always used as signal leads so it doesn't matter if they are resistive - there's no current to speak of. This is particularly true of leads for devices like printers, which are almost always separately powered. Unfortunately the CMM2 puts about 200mA on it, which is probably about 10 times what the lead was intended to carry (but not the limit of the USB port).
Edited 2021-04-24 00:09 by Mixtel90

Mick

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Preliminary MMBasic docs & my PCB designs

Womble

Senior Member

Joined: 09/07/2020
Location: United Kingdom
Posts: 267

Posted: 03:41pm 23 Apr 2021

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Mixtel90 said As I discovered, not all A-B leads are what they appear to be and some use slightly damp string as conductors! Try a different A-B lead, as short as you can comfortably manage.

I agree wholeheartedly. Swapping the USB A-B cable fixed a whole host of wierd problems with my CMM2.

Friet
Newbie

Joined: 16/12/2020
Location: Belgium
Posts: 13

Posted: 11:30am 24 Apr 2021

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All,

Thanks for all the tips!! Indeed the A-B cable dropped the voltage by 1.5V...USB multimeter showed that it had only 3.5V instead of 5V.

I gathered all my A-B cables and started testing, the first one i used already did the trick. Keyboard works !

I managed to get two keyboards of my collection to work : (not on Circuitgizmos list i think)

- HP KU-0316
- HP Wireless Slim Keyboard (Bluetooth dongle) (Weird as it also has a mouse)

Now the fun can start (first some serious studying..as its been over 30 years ago that i did any fun programming..)

Cheers,

Frank

epsilon

Senior Member

Joined: 30/07/2020
Location: Belgium
Posts: 255

Posted: 03:10pm 24 Apr 2021

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Congratulations! Have Fun! Make something cool.

Epsilon CMM2 projects

Mindwarp

Newbie

Joined: 13/02/2021
Location: Canada
Posts: 29

Posted: 01:16am 16 May 2021

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FYI, I just received my retromax and it works with the Best Buy Insignia keyboard.

Mine is from the mouse/kb combo, which also looks like the stand alone one.

https://www.bestbuy.ca/en-ca/product/insignia-optical-keyboard-mouse-combo-english-only-at-best-buy/10620406
https://www.bestbuy.ca/en-ca/product/insignia-wired-keyboard-black-english-only-at-best-buy/10620394
Edited 2021-05-17 05:32 by Mindwarp

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