How to upgrade Geeetech A10 with BIGTREETECH / Fystec Mini12864

I want to show here how to use a Mini12864 Display from BIGTREETECH or Fystec with the Geeetech A10 in (mainly for Klipper but Marlin below!). Caution: I am using here a Bigtreetech display and there are different versions of the fystec displays - pinouts can be different!

First of all have a look at the board and the schematic (GT2560 v3!). The LCD FFC 40pin Cable can be used for other purposes with a FFC 40pin breakout board (0.5 pitch) like this one.

Requirements:

• Mini12864 Display
• FFC 40pin breakout board (0.5 pitch)
• Cables and header pins

optional:

• Backup FFC Cable
• Case (recommended - I use this)

How to do it step-by-step:

I am not responsible for your hardware or software. You do this at your own risk.

Hardware:

1. Solder some connector sockets to the breakout board
2. Cut one of the display cables in half and solder some pins on it so you can plug them into the breakout board
3. The EXP1 and EXP2 have sometime different orientation so it is important to find the correct pins. Both connectors have a GND pin so you can find this with a continuity tester.
4. The FFC 40 pin connector can be mirrord with some cables so it is important to find the correct orientation of it too. On one end is 5V and on one is GND. The orientation is clear by measuring the voltage between the outer pins.

Usually the pin out is (simpler .ods file is in the repository - please use it):

Pin	EXP1	EXP2
1	BEEP	MISO
2	ENC_BTN	CLK
3	LCD_CS	ENC_A
4	LCD_RS	SD_CS
5	LCD_RST	ENC_B
6	RGB_DIN	MOSI
7	NC	SD_DET
8	NC	RESET
9	GND	GND
10	5V	KILL/NC

And the FFC 40 pin connector (PU = hardware pull-up resistor on the board):

MEGA2560 (Arduino)	MEGA2560 (Pin)	MEGA2560 (Name)	Connection	FFC40	FFC40 (reversed)
			5V	40	1
			5V	39	2
3	5	PE3(OC3A/AIN1)	LCM_D6	38	3
34	43	PD0(SCL/INT0)	LCM_D5 (PU)	37	4
9	13	PH1(TXD2)	LCM_D4	36	5
45	54	PC1(A9)	LCM_D7	35	6
8	12	PH0(RXD2)	LCM_EN	34	7
36	45	PD2(RXD1/INT2)	EC_PRESS	33	8
37	46	PD3(TXD1/INT3)	BEEP	32	9
				31	10
				30	11
43	52	PG1(RD)	EC1	29	12
33	42	PL7	EC2	28	13
				27	14
				26	15
				25	16
				24	17
-	30	RESET	Reset	23	18
				22	19
				21	20
				20	21
				19	22
				18	23
35	44	PD1(SDA/INT1)	LCM_RS (PU)	17	24
				16	25
				15	26
				14	27
				13	28
				12	29
15	19	PB0(SS/PCINT0)	SS	11	30
17	21	PB2(MOSI/PCINT2)	MOSI	10	31
16	20	PB1(SCK/PCINT1)	SCK	9	32
18	22	PB3(MISO/PCINT3)	MISO	8	33
				7	34
41	50	PD7(T0)	SD_DETECT	6	35
			3.3V	5	36
			3.3V	4	37
			GND	3	38
			GND	2	39
			GND	1	40

I use the following connection:

FFC40	FFC40 (reversed)	Display
40	1	EXP1_10
39	2	NC
38	3	EXP1_3
37	4	EXP1_1
36	5	EXP1_4
35	6	EXP1_6
34	7	EXP1_5
33	8	NC
32	9	NC
31	10	NC
30	11	NC
29	12	EXP2_3
28	13	EXP2_5
27	14	NC
26	15	NC
25	16	NC
24	17	NC
23	18	EXP2_8
22	19	NC
21	20	NC
20	21	NC
19	22	NC
18	23	NC
17	24	EXP1_2
16	25	NC
15	26	NC
14	27	NC
13	28	NC
12	29	NC
11	30	EXP2_4
10	31	EXP2_6
9	32	EXP2_2
8	33	EXP2_1
7	34	NC
6	35	EXP2_7
5	36	NC
4	37	NC
3	38	NC
2	39	EXP2_9
1	40	EXP1_9

I tried to keep the following unused for other purposes:

• PD2(RXD1/INT2)
• PD3(TXD1/INT3)
• 1x 5V pin
• 1x GND pin

For me the red line on the cable was pin 1 on the EXP connector!

Connected it looks like this:

Firmware:

I mainly use Klipper and Mainsail so I can only confirm it working with it.

Klipper:

• Display:

[display]
lcd_type: uc1701
cs_pin: PE3
a0_pin: PH1
rst_pin: PH0
contrast: 63
encoder_pins: ^PL7, ^PG1
click_pin: ^!PD1

• optional for beeper(untested):

[output_pin beeper]
pin: PD0

• optional for RGB (color can be changed):

[neopixel fysetc_mini12864]
pin: PC1
chain_count: 3
color_order: RGB
initial_RED: 1
initial_GREEN: 1
initial_BLUE: 1

optional if octoprint is not used:

[menu __main __octoprint]
type: disabled

Marlin (untested and incomplete):

For marlin you can find the configuration here, but you have to adjust the pins according to the table above with the Arduino IDE pins. The pins have to be changed in the Marlin/src/pins/mega/pins_GT2560_V3.h file.

That's it!

Time to restart and hope for the best!