Manta M8P i2c_bus name

[Jonathjon]

Basic Information:

Printer Model: V1 MP3DP V5
MCU / Printerboard: Manta M8P V2
Host / SBC: CB1
klippy (14).log (299.3 KB)

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Describe your issue:

…

I am trying to install an AHT20 sensor for chamber temp but having an issue figuring out what the i2c_bus is on the Manta M8P V2. I have read through the manual and searched everywhere I can think of and cant find it anywhere. Any help would be greatly appreciated!

[gaolst]

bigtreetech/Manta-M8P/blob/master/V2.0/Hardware/BIGTREETECH MANTA M8P V2.0 PinOut.png

Official pinout diagram with pin names from BTT for Manta M8P v2.0

pins:
SDA-PC9
SCL-PA8

Wiring, official manual, page 16

bigtreetech/Manta-M8P/blob/master/V2.0/BIGTREETECH MANTA M8P V2.0 User Manual.pdf

all I2C definitions from klipper source for STM32 CPUs

DECL_ENUMERATION(“i2c_bus”, “i2c1”, 0);
DECL_CONSTANT_STR(“BUS_PINS_i2c1”, “PB6,PB7”);
DECL_ENUMERATION(“i2c_bus”, “i2c1a”, 1);
DECL_CONSTANT_STR(“BUS_PINS_i2c1a”, “PB8,PB9”);
DECL_ENUMERATION(“i2c_bus”, “i2c2”, 2);
DECL_CONSTANT_STR(“BUS_PINS_i2c2”, “PB10,PB11”);
#if CONFIG_MACH_STM32F2 || CONFIG_MACH_STM32F4
DECL_ENUMERATION(“i2c_bus”, “i2c3”, 3);
DECL_CONSTANT_STR(“BUS_PINS_i2c3”, “PA8,PC9”);
#if CONFIG_MACH_STM32F2 || CONFIG_MACH_STM32F4x5
DECL_ENUMERATION(“i2c_bus”, “i2c2a”, 4);
DECL_CONSTANT_STR(“BUS_PINS_i2c2a”, “PH4,PH5”);
DECL_ENUMERATION(“i2c_bus”, “i2c3a”, 5);
DECL_CONSTANT_STR(“BUS_PINS_i2c3a”, “PH7,PH8”);
#endif
#endif

most probably it will be i2c3

[Jonathjon]

@gaolst

most probably it will be i2c3

Am I missing something else that has to be there?

[gaolst]

From your klippy log
main MCU report following

Loaded MCU ‘mcu’ 108 commands (v0.12.0-132-ge37b007f / gcc: (15:8-2019-q3-1+b1) 8.3.1 20190703 (release) [gcc-8-branch revision 273027] binutils: (2.35.2-2+14+b2) 2.35.2)
MCU ‘mcu’ config: ADC_MAX=4095 BUS_PINS_i2c1_PB6_PB7=PB6,PB7 BUS_PINS_i2c1_PB8_PB9=PB8,PB9 BUS_PINS_i2c2_PB10_PB11=PB10,PB11 BUS_PINS_spi1=PA6,PA7,PA5 BUS_PINS_spi1a=PB4,PB5,PB3 BUS_PINS_spi2=PB14,PB15,PB13 BUS_PINS_spi2a=PC2,PC3,PB10 BUS_PINS_spi3a=PC11,PC12,PC10 BUS_PINS_spi4=PE13,PE14,PE12 BUS_PINS_spi5=PF8,PF9,PF7 BUS_PINS_spi5a=PH7,PF11,PH6 BUS_PINS_spi6=PG12,PG14,PG13 CANBUS_BRIDGE=1 CLOCK_FREQ=400000000 MCU=stm32h723xx PWM_MAX=255 RECEIVE_WINDOW=192 RESERVE_PINS_CAN=PD0,PD1 RESERVE_PINS_USB=PA11,PA12 RESERVE_PINS_crystal=PH0,PH1 STATS_SUMSQ_BASE=256 STEPPER_BOTH_EDGE=1

Highlighting

BUS_PINS_i2c1_PB6_PB7=PB6,PB7 BUS_PINS_i2c1_PB8_PB9=PB8,PB9 BUS_PINS_i2c2_PB10_PB11=PB10,PB11

So you don’t have i2c3

[gaolst]

as you can see firmware have this section

#if CONFIG_MACH_STM32F2 || CONFIG_MACH_STM32F4
DECL_ENUMERATION(“i2c_bus”, “i2c3”, 3);
DECL_CONSTANT_STR(“BUS_PINS_i2c3”, “PA8,PC9”);

It’s possible that it just missing CONFIG_MACH_STM32H723 there
and i2c3 is not present

if you are building and flashing your MCU firmware from vanilla klipper - then you can try to add it, or override pin names for existing i2c1.

[Jonathjon]

This is on an already up and running printer so not flashing anything. It was flashed for the correct board so not sure why that’s not correct.

@gaolst

or override pin names for existing i2c1.

How would I go about doing this?

[gaolst]

Overriding also require building and flashing MCU.

I’m not sure if it’s possible but maybe there are some way to use software based I2C where you would define your pins.

[Jonathjon]

Ok I gave this a try…

And this was the result…

klippy (15).log (6.8 MB)

[NAPCAL]

You might have to enable the I2C bus under the Linux OS.

[gaolst]

Great, so Software i2c was accepted, that error came from your MCU when it did try to send bytes.

BTW is your AHT10 connected ?

Try to change i2c_address to 0x39.

[Jonathjon]

@gaolst

BTW is your AHT10 connected ?

Directly to the i2c connector on the M8P

@gaolst

Try to change i2c_address to 0x39.

I will give that a try

[gaolst]

additionally try to switch pins in config
PA8 - SDA
PC9 - SCL

[Jonathjon]

Just tried switching it to the other address and got the same error. I will try swapping the pins and see if that does anything

[Jonathjon]

OK I swapped the pins and tried both addresses still the same
MCU 'mcu' shutdown: soft_i2c NACK

Also I just realized that this AHT20 I have is also a BMP280 so I’m not sure if that changes anything or not

[gaolst]

try to use BMP280

because for AHT20 i found this in klipper:

Compatible Sensors:
AHT10 - Tested w/ BTT GTR 1.0 MCU on i2c3
AHT20 - Untested but should work
AHT21 - Tested w/ BTT GTR 1.0 MCU on i2c3

[Jonathjon]

Ok I will give that a shot. I just started a print so once that’s done I will see if that makes any difference! I will report back once I try it. Thanks for all the help!!!

[Jonathjon]

Ok switching it to the BMP280 got it working. Its showing temp and pressure. How would I get the humidity from it?

[gaolst]

BME280 reports all 3 measures.
how to display it - it’s more about fluidd/mainsail setup.

[Jonathjon]

@gaolst

how to display it - it’s more about fluidd/mainsail setup.

Ok. I am using Mainsail. I will try and see what I can find about displaying that. Thanks

[eoverton]

I’m trying to do exactly the same thing with an AHT20 (or AHT10 or BMP280) on a Manta M8P with CB-1 processor on it. Can you post your final “config,” so I can see what you had toggled where, now that you have it working?