Logic Level shifter for 12864 display on Duet 2 Wifi

[A Former User]

@antlob think so, but probably easier to reference the stuff we published at https://easyeda.com/oliof/duet2wifi-lcd12864-adapter (it should at least be in sync with the attached patch)

[antlob]

@bearer Perfect! I'll give it a try later today.

[antlob]

@bearer Didn't work, I get a blank screen, it turns on but is blue, nothing else, is the same as to give it 5v and ground.

What I did was to use the Duet2CombinedFirmware-rrf3-lcd.bin file and update the firmware with it.

I saw that attached you had this file lcd12864rrf2.patch. Should I upload it in the Display menu in the DWC? Also, the patch says RRF2 so Will it work on RRF3?

Sorry for having so many questions.

[A Former User]

@antlob said in Logic Level shifter for 12864 display on Duet 2 Wifi:

I saw that attached you had this file lcd12864rrf2.patch

no that is for applying to the 2.05.1 source code to build it yourself.

Didn't work, I get a blank screen, it turns on but is blue, nothing else, is the same as to give it 5v and ground.

you have uploaded a set of menu files? (its kinda like batteries .. not included)

[Schmart]

@antlob did you enable and configure the display with M918 in your config.g as well?

[antlob]

@bearer OK, so the menus are uploaded manually ... OK. So, if I don't have one I get a blank display? Finally could open the patch and saw that it is a library to compile, how silly of me. Do you know where can I find an example of a menu for LCD12864? Many thanks!

[A Former User]

take your pick https://forum.duet3d.com/search?term=menu files

(and https://duet3d.dozuki.com/Wiki/Duet_2_Maestro_12864_display_menu_system )

[antlob]

@Schmart Yes, actually rereading all the threads and a message you sent about the use of M918, in my case I put M918 P1 E4 F2000000, since my display is a 12864 with a ST7920. But maybe all my problem is that I don't have a menu and therefore there's nothing to show, rigth?

[antlob]

@bearer OK, so I just upload them and that's it?

[antlob]

@bearer Did a little reading on the links you sent me, used this one https://github.com/jadonmmiller/UltimateDuetMenuSystem/releases follow the instructions and a funny thing happened. When uploading the Zip file from the display menu in DWC and rebooted everything stopped working. I took out the SD card and it turns out that all the /sys directory was written with the menu files it erased the existing files and on the /menu directory was nothing. Luckily had a backup so arranged everything and put the menu files in their corresponding directory but still can't make the LCD12684 to work. Have even rewired everything just in case and the result the same. Maybe is the firmware I'm using is the one you gave me the link https://www.dropbox.com/s/f7fjuu7f0wcf7dc/Duet2CombinedFirmware-rrf3-lcd.bin?dl=1. Don't know what else to do.

[A Former User]

@antlob i never had any success with uploading macros or menu files through dwc, but erasing existing files is new, sounds like an issue with dwc.

i didn't do anything but M918 P1 E2, put the files in /menu, wired according to the schematic and the firmware with the patch. seems to work for me and others before me so odds are you've missed a step or your display has a different pinout to the reprap smart grpahics controller.

[Schmart]

@antlob even without menu files, if you do a firmware upgrade from DWC, a message "Upgrading firmware..." should be shown on the display (providing the firmware was compiled with the correct font set).

If no text appears during a firmware upgrade, other than pinout, it could be one of the issues from this post as well, mentioning the contrast trimpot and such.

I didn't read back this entire thread, but have you seen the display working correctly before?

[antlob]

@bearer @Schmart First of all sorry for not replying until today, yesterday couldn't find time to continue. I know I say it everytime I write but I'm really grateful for all the help you've given me so far, without you gys I counldn't by any change connect the display.

I think that I've read in diagonal all the posts about this LCD and all the suggested help you adviced, even a guide to connect the Ender 3 to Duet Maestro. Since I was running RRF 3.1.1 and then installed @bearer RRF 3.0 I thought that maybe I needed to wipe and do a clean install. What I did was:

• Erase the Duet
• Using BOSSA uploaded the @bearer firmware version 2.05
• Downloaded this menu https://github.com/mudcruzr/Duet-Maestro-12864-Menu-Files
• Copy again all the sys and rest of menus

What happened?

• The same issue but in a thread of another post @dc42 suggested to another person put in the terminal M918 P1 and then voilà the display worked. The funny thing is that in my config file at the end was the M918 P1 E-4 F2000000. What I did was take out the frequency parameter and the display worked.
• On DWC the menu tab was not displayed.
• The encoder works but cannot select anything, the press doesn't do anything.

Then I erased the Duet again and did a clean install of @bearer RRF 3.0. And have the following issues:

• On reboot the display is blank (is lighted but with no text on the matrix).
• I have to manually type M918 P1 E-4 and then the display works
• The encoder works but can't select anything, nothing happens when I press the encoder button.
• The display show correctly the temps, coordinates.
• In DWC now I have the menu tab

My thoughts about my issues are the following:

• The encoder press must have a command or something that I'm missing in the menus since they were made for a Duet Maestro. I know I have to dig in every menu file to adapt it to my Duet 2 Wifi.
• I can't understand why in my config.g the M918 doesn't work

What I haven't find yet is if there's a guide to create menus and the usage of encoder. Could you give me a little assistance please?

[A Former User]

@antlob said in Logic Level shifter for 12864 display on Duet 2 Wifi:

Then I erased the Duet again and did a clean install of @bearer RRF 3.0. And have the following issues:

On reboot the display is blank (is lighted but with no text on the matrix).
I have to manually type M918 P1 E-4 and then the display works
The encoder works but can't select anything, nothing happens when I press the encoder button.
The display show correctly the temps, coordinates.
In DWC now I have the menu tab

would suggest one of us messed up the enc_sw connection and/or code. i didn't explicitly test the encoder as i won't use it, however its a simple normally open switch to ground, just like enc_a/b. starting to look like i won't revisit this for a couple of weeks (one handed bandit for a while)

[antlob]

@bearer said in Logic Level shifter for 12864 display on Duet 2 Wifi:

one handed bandit for a while

Sorry @bearer, since I'm from Spain and not a native English speaker don't understand the "one handad bandit for a while". Do you have, by any chance, the master of your fork so maybe I can dig a little bit and try to find out why the encoder's push button does not work?

[A Former User]

(temporarily disabled hand, so only one working hand left for a while)

anyways its all in the thread, i haven't forked the code
https://forum.duet3d.com/post/147841
https://forum.duet3d.com/post/147937

[antlob]

@bearer OK, hope you get better!

[oliof]

@antlob the encoder button is also something I had trouble with -- but other than with your issue, I got "ghost" clicks with the 12864 I tried. I blamed that on bad wiring at the time since I know that everything works fine on the Duet Maestro.

Considering the manual entry of M918 P1 -- I had a similar issue with the 12864 on Maestro where the first command would enable the screen but the graphics would be corrupted. I solved this by doing

M918 P1
G4 P1000
M918 P1

I.e., initializing twice with a one second pause in between.

(coincidentally, I tried my Creality Minipanel this afternoon and while I didn't get the display to show anything, I got Encoder wheel and button working -- tested with a very simple main menu that just calls Macros running various M291 commands, i.e. creating disimissable popups I can observe in DWC).

[A Former User]

for what its worth i had no issues on the Maestro, beyond the polarity on the geeetech display headers being wrong and the encoder skipping two entries which was solved by E2 in M918 as such I didn't bother testing on the Wifi board.

I'm guessing dc42 wil be done with his 756x stuff by the time I get the cast* off and will poke it some more then

*) give the kids alcohol before the sports get them!

[antlob]

@oliof Thanks! Yesterday came to the same conclusion as you did the same, initializing twice and it works. About the button I dig in some Arduino forums and tested the encoder, when I press it closes a circuit to ground so the hardware is fine. In my case, the rotary works just fine is only the switch button.
When I donwloaded @bearer's patch, in it is clearly defined that the pin used for the encoder switch is number 8 and that it connects to CONN_LCD 10.

+// 12864 LCD
+// The ST7920 datasheet specifies minimum clock cycle time 400ns @ Vdd=4.5V, min. clock width 200ns high and 20ns low.
+// This assumes that the Vih specification is met, which is 0.7 * Vcc = 3.5V @ Vcc=5V
+// The Duet Maestro level shifts all 3 LCD signals to 5V, so we meet the Vih specification and can reliably run at 2MHz.
+// For other electronics, there are reports that operation with 3.3V LCD signals may work if you reduce the clock frequency.
+// ST7920 doesn't allow SCK/MISO signals when CS is not asserted, therefore the AND gate on the Maestro
+constexpr uint32_t LcdSpiClockFrequency = 2000000; // 2.0MHz -- Top View --
+constexpr Pin LcdCSPin = 7; //connsd.7 --> gate -> exp1.4
+constexpr Pin LcdBeepPin = 60; //connlcd.4 -> exp1.1
+constexpr Pin EncoderPinA = 85; //connlcd.8 -> exp2.5
+constexpr Pin EncoderPinB = 25; //connlcd.6 -> exp2.3
+constexpr Pin EncoderPinSw = 8; //connlcd.10 -> exp1.2

Seeing other diagrams in this post and also Schenk's tried out to connect the ENC_SW to the original CONN_SD.7 and it worked! But now I had an important issue, the 3.3v that should go to the LCD_CS were in an open circuit, but, nevertheless the LCD worked, maybe my model was one of the ones that can operate with 3.3 v signals. Now, since LCD_CS was always on 3.3 v, and it needed to be for the AND gates to work, I connected it directly to a 3.3 v of the expansion and now the display starts just fine and have even taken the delay in the config.g. I assume that on power up, the M918 preceeds the initialization sequence in the Duet and therefore we had to make a delay in order of it to work. I bet that if you take the first M918 and just use a delay of 2 seconds it will work just fine.

So, my wiring is as of @bearer's patch and schematics but connecting EXP1.1 to CONN_SD.7 and the SN74HCT08DR 2A or pin4 to a 3.3 v source.

Now I have to test the SD card, need to find another one and see if I can read it.