From 52a8afba43e4997764283b868c017bc261a56896 Mon Sep 17 00:00:00 2001 From: Kevin O'Connor Date: Mon, 20 Jun 2022 12:58:05 -0400 Subject: [PATCH] docs: Note mcu types with i2c_speed support in Config_Reference.md Signed-off-by: Kevin O'Connor --- docs/Config_Reference.md | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md index ac77b941..be33c723 100644 --- a/docs/Config_Reference.md +++ b/docs/Config_Reference.md @@ -1536,9 +1536,9 @@ number of sections with an "mpu9250" prefix). # Default is 104 (0x68). #i2c_mcu: #i2c_bus: -#i2c_speed: +#i2c_speed: 400000 # See the "common I2C settings" section for a description of the -# above parameters. +# above parameters. The default "i2c_speed" is 400000. #axes_map: x, y, z # See the "adxl345" section for information on this parameter. ``` @@ -4224,6 +4224,15 @@ support for error recovery varies between each micro-controller type. It is generally recommended to only use i2c devices that are on the same printed circuit board as the micro-controller. +Most Klipper micro-controller implementations only support an +`i2c_speed` of 100000. The Klipper "linux" micro-controller supports a +400000 speed, but it must be +[set in the operating system](RPi_microcontroller.md#optional-enabling-i2c) +and the `i2c_speed` parameter is otherwise ignored. The Klipper +"rp2040" micro-controller supports a rate of 400000 via the +`i2c_speed` parameter. All other Klipper micro-controllers use a +100000 rate and ignore the `i2c_speed` parameter. + ``` #i2c_address: # The i2c address of the device. This must specified as a decimal