Configuring 12864 LCD on Maestro?

3dmntbighker

Whew, ok.. pretty confusing thread. I'm ready right now to connect the Maestro to my stock Ender 3 Pro display. Do we have consensus on what needs to be done? If the the display is standard off the shelf used by Creality why is flipping the cable necessary? Do we actually need two cables? Is the encoder finally reversed when all is wired, or is there a way to correct that? The info I found is pretty limited on schematics. What connectors should be used on the Maestro end, and the display end?

dc42

The most common connection scheme for 12864 displays is the one used by the RepRapDiscount Smart Graphics Controller. This is an open source design described at https://reprap.org/wiki/RepRapDiscount_Full_Graphic_Smart_Controller. That was in turn based on the connections used by 20x4 text displays. Unfortunately the display on the Ender 3 uses a different scheme.

A single 10-way connection would in principle be sufficient for a display without a SD card socket, but doesn't provide enough pins for both the LCD and the SD card.

3dmntbighker

@dc42 said in Configuring 12864 LCD on Maestro?:

The most common connection scheme for 12864 displays is the one used by the RepRapDiscount Smart Graphics Controller. This is an open source design described at https://reprap.org/wiki/RepRapDiscount_Full_Graphic_Smart_Controller. That was in turn based on the connections used by 20x4 text displays. Unfortunately the display on the Ender 3 uses a different scheme.

A single 10-way connection would in principle be sufficient for a display without a SD card socket, but doesn't provide enough pins for both the LCD and the SD card.

Figures And apparently Creality inverted the pins. The display has no SD card. They managed to get the display and the encoder over a single 8 pin cable to their CPU board. I guess the Maestro has pins needed for the encoder on one connector and the display on another one.

Agniusm

@3dmntbighker, Yes, there is consensus. There are 2 ways you can connect your display.

You use your cable, cut one end on it, get some dupont connectors and wire it according to this diagram:

If encoder is reversed, you flip 2 bottom wires(as per pic) on Duets EXP2(left connector on pic)
method is to use 2 10pin cables(so you need to buy another one)
a. on duet, connect it normal way
b. on ender 3 display, connect it flipped where locator clips face beeper.
Duet exp1 to LCD exp1 flipped
Duet exp2 to LCD exp2 flipped
Dont forget to add M918 P1 E4 to your config.g

Agniusm

Some more of the insights. Using two cable method lcd shows some artifacts. When connected to exp3 and using diy'ed single cable artifacts are absent

dc42

If encoder is reversed, you flip 2 bottom wires(as per pic) on Duets EXP2(left connector on pic)

You can also reverse the encoder direction in the M918 command that configures the display and encoder.

3dmntbighker

Thanks for all the help. My cables will arrive tomorrow.

Has anyone determined if the Ender display can support the second SD card? And what may be lacking to add it? Just curious if a full size SD card is possible to add.

3dmntbighker

My cables arrived, and I have the display working. It seems the default menu system with RC5 doesn't work out of the box. I messed around a bit before leaving for work, but has anyone put together a working menu system (starting point) for the Ender 3. It appears that a single file makes the whole RC5 menu system operate named "menu" that is absent on my Maestro. (edit: OK, I noticed this is mentioned in the RC5 release notes, so I guess DC is workin on it already)

I also notice the artifacts mentioned with the two cable solution. I hope we can track down the cause at some point.

Thanks to everyone who has pitched in.

Agniusm

Adding SD card to the LCD is no go. You can add it as a separate module you can get on ebay for few quid:
Just for illustration:
https://www.ebay.com/itm/3D-printer-SD-external-card-reader-MKS-Slot-V1-1-and-MKS-Slot2-2-8-inch-U-disk/222920755412?hash=item33e71cc8d4matuTHLib1EHTKR3OVhUcHw:rk:1:pf:0

I have attached somewhat fixed basic menu few posts above

3dmntbighker

@agniusm said in Configuring 12864 LCD on Maestro?:

@arnd13
Looks like vcc, gnd, buzz and enc_sw will work on exp1, you only need to cut slot in lcd connector and flip ribbon cable?! I will try that.
Another way is just to cut ribbon cable and crimp dupont pins, then use connectors found on pc for power,hdd, reset. They come in multiple sizes and could be salvaged

I just filed off the bit on the cable connector that indexes the cable. Less than a minute and I didn't butcher the board

Agniusm

@3dmntbighker I know, but its just easier to nip the slot out with snips

3dmntbighker

@agniusm said in Configuring 12864 LCD on Maestro?:

@3dmntbighker I know, but its just easier to nip the slot out with snips

If I want your opinion I'll tell you what it is

Agniusm

Sorry, what?

3dmntbighker

@agniusm said in Configuring 12864 LCD on Maestro?:

Sorry, what?

Kidding dude

3dmntbighker

Are the menu files that M3D ships on the Maestro available zipped somewhere? My SD card bit the dust today, and I had no backup. Yeah, so a backup admin for NASA had no backup. Ughhh. I got the ones agniusm linked, but I'd like the original ones, or for that matter a zip file of the entire SD card. All I could find was the generic one without the menu directory.

dc42

I've put a copy on the ones that came on my Crane at https://www.dropbox.com/s/f6jthzr7vh8619g/MenuFiles.zip?dl=0. They may not be up to date, and they could almost certainly be simplified.

3dmntbighker

@dc42 said in Configuring 12864 LCD on Maestro?:

I've put a copy on the ones that came on my Crane at https://www.dropbox.com/s/f6jthzr7vh8619g/MenuFiles.zip?dl=0. They may not be up to date, and they could almost certainly be simplified.

Thanks bro

Cata

I'm tired of waiting support in the duet for this lcd, buy 2 maestro to enjoy a simple lcd on my printers

dc42

@cata, the Duet WiFi and Ethernet do not have the hardware needed to level shift the LCD signals to 5V and gate the SPI clock for compatibility with common 12864 LCD/encoder combos. That's the main reason why the firmware builds for those boards don't include the 12864 support.

Cata

@dc42 a level shifter is too basic to implement, not the same with the firm support. Why not implement in the firm and let the users works with the level shifter?