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Forum Index : Microcontroller and PC projects : Wierd LCD initalize problem...
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Grogster Admin Group  Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
Hi  7" SSD1963 panel, with minimal 64-pin MM+ chip to control the screen. Works. .....until you turn off the power. When I cycle power, the LCD does NOT re-initialize. No GUI commands work, including GUI TEST LCDPANEL. Nothing can be drawn on the screen. The BACKLIGHT command has no effect. The only way I can get it to work again, is to: OPTION LCDPANEL DISABLE ...and then.... OPTION LCDPANEL SSD1963_7,L Then it works again just fine - until I turn off the power again, and then we are back to the same issue in that I have to disable and re-enable the LCDPANEL before it will work again. I have never seen this behaviour before. Can anyone suggest anything that might be causing this issue? 3v3 and 5v connected to 7" panel, via two external buck-converter modules. I will upload some photos shortly, of how I have everything connected. EDIT: Here is the photo of my arrangement:  The MM+ board talks to the 7" LCD, and the PSU on the left of the image takes a 12v input and provides a 3v3 and 5v supply to the MM+ board. Smoke makes things work. When the smoke gets out, it stops! |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
I tried a brand-new 7" LCD on this just now, and exactly the same problem. Changed 100uF caps just above the 3-way connector on the MPD board, to 1000uF 6v3 thinking perhaps there was some kind of voltage-drop issue, but that also did not help. Stumped.  Smoke makes things work. When the smoke gets out, it stops! |
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| erbp Senior Member  Joined: 03/05/2016 Location: AustraliaPosts: 195 |
How you tried re-flashing firmware on the MM+? We all know that often fixes weird problems - not saying it will this time but worth a try. Phil. |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
Yes, worth a try. I will do that. FW in it at the moment is 5.0408, which has historically been rock-solid. Smoke makes things work. When the smoke gets out, it stops! |
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Geoffg Guru  Joined: 06/06/2011 Location: AustraliaPosts: 3308 |
I wonder if the MM+ is kept powered on somehow. Perhaps the USB-to-Serial bridge is somehow supplying the power? Then, when you cycle the power, only the LCD panel would be reset. Do you get an error message when you access the LCD panel? What happens when you use GUI RESET LCDPANEL ? EDIT: The other possibility is that the Reset pin on the SSD1963 panel is not connected to the Micromite. Geoff Geoff Graham - http://geoffg.net |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
Definitely not the USB, as that is not connected when I cycle the power when I have this problem, so it SHOULD just restart. IE: Can't be parasitic power, and the MPD board does not route the UBB 5v line past the USB socket. It's really odd. This is not my first LCD either.... No error messages when I type something like GUI TEST LCDPANEL, but you just get nothing on the screen at all. DISABLE and OPTION LCDPANEL and you are away again. I had forgotten about GUI RESET LCDPANEL - thanks for the prod. I will add that to the code after, say, 1 second of startup delay. Smoke makes things work. When the smoke gets out, it stops! |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
OK, Geoff is onto something here.... GUI RESET LCDPANEL revives the LCD if it does not fire up correctly, and then the LCD is working again without having to do the DISABLE and OPTION LCDPANEL. When I put that at the top of my code, the screen is working 100% of the power cycles now. Thanks, Geoff!  EDIT: "The other possibility is that the Reset pin on the SSD1963 panel is not connected to the Micromite." No, it is connected to pin 28 on this board. Smoke makes things work. When the smoke gets out, it stops! |
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| PeterB Guru Joined: 05/02/2015 Location: AustraliaPosts: 655 |
G'Day Grogster et al You do pick some LU LUs Or have I said that before?  If Geoff's ideas fail then, I am suspicious of mixing RF with proper electronics. I think you have had quite a lot of experience in that but just in case........ Peter |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
I do, and you have. Perhaps I am jinxed....  Smoke makes things work. When the smoke gets out, it stops! |
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| Geoffg Guru Joined: 06/06/2011 Location: AustraliaPosts: 3308 |
The fact that GUI RESET LCDPANEL works suggests that the Micromite is powering up before the SSD1863... something to do with the power supply sequencing perhaps? You could delay the Micromite startup with a capacitor on MCLR but probably the simplest is to just keep using GUI RESET LCDPANEL. Geoff Graham - http://geoffg.net |
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CaptainBoing Guru Joined: 07/09/2016 Location: United KingdomPosts: 2171 |
interesting thread. I too have had very occasional init failures but they go away when I try to find them and become non-traceable. I think I am going to adopt a standard procedure that I GUI RESET LCDPANEL at the end of my preamble code in anything I write from now on... does no harm and might be the solution to a really annoying "ghost" cheers |
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| Grogster Admin Group Joined: 31/12/2012 Location: New ZealandPosts: 9755 |
@ Geoff - Yeah, I would have thought so too, but both the LCD and the MM+ are being fed from the same 3v3 supply. The 5v supply, is only there for the HC12 and the 7" LCD backlight - the "5v" pin. For whatever reason, the manual reset totally fixes the problem, so I am a happy chappy. @ CaptainBoing - I would, if you have ever had problems with LCD initialization. This has been a non-issue for me up until now. The LCD always initializes fine. But at least we have the manual reset command, cos without it, we'd really be stuck. Smoke makes things work. When the smoke gets out, it stops! |
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| PeterB Guru Joined: 05/02/2015 Location: AustraliaPosts: 655 |
I know I'm flogging a dead horse but, CB, does your system that fails also use 433MHz? Peter |
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| CaptainBoing Guru Joined: 07/09/2016 Location: United KingdomPosts: 2171 |
It does, but it's not close. I thought it was due to GSM interference at one point so I have also thought about the potential for something else creeping in. The problem was, it occurred about four or five times over two occasions and never since. Moving it didn't seem to make any difference and the HC-12 wasn't active at the time. Having seen a problem it is always at the back of your mind that it will occur again - any mystery can (and usually does) resurface. The system was evidently alive underneath as I output status and tracing to the console, even though en in anger it will be disconnected. It was just a blank screen. - strangely I did get the white-then-black of initialization... so it was like it had tried. I have already retro-fitted the code to include the software reset but currently it is a solution looking for a problem as i never got to the bottom of or - nor had the opportunity |
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| PeterB Guru Joined: 05/02/2015 Location: AustraliaPosts: 655 |
Good morning CB, well it is here. Back in January when every man and his dog was busy chasing the problem with VAR SAVE etc you said, at the end, you had been "lurking in secret terror" over the problem because you had many systems in place. We have several 7 in touch screens with a magnificent Grogster board out in the world and more to come so I am in your position. It does make life worth living doesn't it? We do not have RF and I have had no complaints in over a year but farmers probably would just ignore it anyway. Peter |
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| CaptainBoing Guru Joined: 07/09/2016 Location: United KingdomPosts: 2171 |
Morning Peter... (it is here now and very pleasant too) Yes I remember the thread. There is no link to the many though - they don't have displays. They are small 28 pinners stuck in large ceiling roses to control the lighting pendant below them with an SSR in snooker clubs. They communicate with a central system through HC-12s so they can remote switch the lights. Now one of these clubs has no requirement for a PC based controller - that is where an MMX has gone in and it was one that had this weird LCD start up thing. The 433MHz stuff in these clubs is quite busy - the controller is constantly polling the other slave controllers and issuing commands (turn the light on/off) mainly and gathering timing so the club member can me billed for table time. The secret terror is because when installed, each of these slaves (and there are a lot of them spread all over), all require config the first time... their node number, their "human friendly" name and a model type etc. so when the controller discovers it, it can report back what its purpose in life is and the controller can then map a table number on its screen to a table light module... it works really well - far better than I had hoped from the get-go. If the VAR SAVE problem had not been squashed (they are all using 5.04.08) I would have had to visit each one, flash the firmware and re-config... can you imagine!? Visiting the MMX to update the software is something I have already planned but it isn't urgent as the whole thing is *very* well behaved. The turn-key aspect is very refreshing, the master is literally up and running in about 3 seconds from switch on. The slaves are on all the time, the fitting was a piece because none of the existing wiring got changed so all the old switches are in the on position. The slaves default (between wake-up and discovery) to light on, so in the event of failure they can still control the tables just by the switch panel on the wall. Once the master comes back on line though it will get a storm of stored "UXP" messages suggesting the staff are doing "mates rates" |
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