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LouisG
Senior Member

Joined: 19/03/2016
Location: Australia
Posts: 129

Posted: 06:56am 02 Mar 2018

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Wondering if any of you guys can help with this odd phenomenon.

I assembled one of Grogster�s E100 kits and fired it up with a 5� screen. Using MMedit via USB, I set up all the options to create a self-contained computer. On adding a PS2 keyboard, it worked fine. However, when I went back to MMedit I found I had lost USB communication with the E100.

Repeated attempts at re-establishing comms were of no avail, though the self-contained computer continued to be operational.

Investigating further I found that separating the LCD screen from the E100 allowed communication to be restored. I also began disabling the options one by one, each time reconnecting the screen and found that

OPTION LCDPANEL SSD1963_5, LANDSCAPE, 48

by itself, with no other option activated, was causing the communication to fail. Setting OPTION LCDPANEL DISABLE restored communication.

Apart from this USB comms phenomenon, everything seems to be in order. What haven�t I taken into account or what am I doing wrong?

My setup:
Explore 100 ver B
SSD1963QL9 5�
MM+ 5.04.09 Beta 4
MMedit 3.7.0
Option List:
OPTION COLOURCODE ON
OPTION DISPLAY 24, 66
OPTION LCDPANEL SSD1963_5, LANDSCAPE, 48
OPTION TOUCH 1, 40, 39
OPTION KEYBOARD US
OPTION SDCARD 47
OPTION LCDPANEL CONSOLE

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2959

Posted: 08:51am 02 Mar 2018

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Hi Louis,

Seen this kind of thing many times before - typically it is a 'power supply' issue.

A few questions:

1> How are you powering this setup? If via USB only, have you tried an external PSU (via the jack socket). Remember to remove the USB power jumper first to potentially avoid 'back-feeding' 5v into your computer!

2> Which version of the E100 PCB do you have (v1B, v1C, v1D)? SORRY - Just re-read your post and see it is v1B

3> What if you physically remove the PS2 keyboard - does it then 'behave' via MMEDIT?

With a TFT and a PS2 keyboard, I have seen big variation in the current requirements on the 5v rail (due to these 'external' devices).

Will await feedback to see what to suggest next . . .

WW
Edited by WhiteWizzard 2018-03-03

WhiteWizzard
Guru

Joined: 05/04/2013
Location: United Kingdom
Posts: 2959

Posted: 08:54am 02 Mar 2018

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By the way - the 5" TFTs I have here have more impact on similar issues than a 4.3" or 7".

With the 5" screens I always try them with the MM at CPU 80 - this fixes 'corrupted' characters on the TFT when used as a standalone.

So do you have another TFT size to try? IF not - then also set CPU 80 for now . . .

LouisG
Senior Member

Joined: 19/03/2016
Location: Australia
Posts: 129

Posted: 09:25am 02 Mar 2018

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Thanks WW.

Will try your suggestions. Am kicking myself for not thinking of the power supply angle.

Will advise.
Louis

MicroBlocks

Guru

Joined: 12/05/2012
Location: Thailand
Posts: 2209

Posted: 03:38pm 02 Mar 2018

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Also check your cables. Some of the USB cables have very thin wires and this can cause a voltage drop that is maybe to much. Also tiny wires do not allow for much current.

Microblocks. Build with logic.

LouisG
Senior Member

Joined: 19/03/2016
Location: Australia
Posts: 129

Posted: 04:14pm 02 Mar 2018

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All fixed now. I used a separate power supply.

Thanks WW. You're a wizard.
Thanks MB.
I learned a lot.

L.

WhiteWizzard
Guru

Joined: 05/04/2013
Location: United Kingdom
Posts: 2959

Posted: 04:23pm 02 Mar 2018

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Great to hear that you're up and running

Have Fun!

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