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products:sbc:common:applications:gpio:i2c

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products:sbc:common:applications:gpio:i2c [2022/07/12 04:33]
nick
products:sbc:common:applications:gpio:i2c [2023/11/07 04:51] (current)
nick [Enable I2C]
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 ===== Introduction ===== ===== Introduction =====
  
-This document mainly introduces the usage of I2C bus on [[products:sbc:common:applications:gpio:40pin-header|40-Pin Header]].+This page introduces the usage of I2C bus on [[products:sbc:common:applications:gpio:40pin-header|40-Pin Header]].
  
 ===== I2C Information ===== ===== I2C Information =====
  
-<tabbox VIM1/2+|            I2C      PIN      ^  GPIO Name  ^  DT Overlays Node  ^  Bus Number  ^  Device Node  ^ 
-**I2C A** \\ +^  VIM1/  |  I2C A   |  22(SCL  GPIODV_25  |  i2c0              |  0           |  /dev/i2c-0   | 
-''Sensor SCL'' <-> ''I2C_SCK_A'' (PIN 22) \\ +| :::       | :::      |  23(SDA  GPIODV_24  | :::                | :::          | :::           | 
-''Sensor SDA'' <-> ''I2C_SDA_A'' (PIN 23\\ +| :::        I2C B    25(SCL  GPIODV_27  |                  |  1           |  /dev/i2c-1   | 
-''Sensor GND'' <-> ''GND'' \\ +| :::       | :::      |  26(SDA)  |  GPIODV_26  | :::                | :::          | :::           | 
-''Sensor VCC'' <-> ''5V'' or ''3.3V'' %%//%%depends on your sensor \\ +^  VIM3/3L   I2CM   22(SCL)  |  GPIOA_15    i2c3              |  3            /dev/i2c-3   | 
-**I2C B** \\ +| :::       | :::      |  23(SDA  GPIOA_14   | :::                | :::          | :::           | 
-''Sensor SCL'' <-> ''I2C_SCK_B'' (PIN 25\\ +| :::        I2C AO  |  25(SCL  GPIOAO_2   |                  |  4           |  /dev/i2c-  | 
-''Sensor SDA'' <-> ''I2C_SDA_B'' (PIN 26\\ +| :::       | :::      |  26(SDA)  |  GPIOAO_3   | :::                | :::          | :::           | 
-''Sensor GND'' <-> ''GND'' \\ +^  VIM4      I2CM F  |  22(SCL)  |  GPIOY_17    i2cm_f            |  5            /dev/i2c-5   | 
-''Sensor VCC'' <-> ''5V'' or ''3.3V'' %%//%%depends on your sensor +| :::       | :::      |  23(SDA  GPIOY_18   | :::                | :::          | :::           | 
-<tabbox VIM3/3L+| :::        I2CM A  |  25(SCL)  |  GPIOT_20    i2cm_a            |  0            /dev/i2c-0   | 
-**I2C 3** \\ +| :::       | :::      |  26(SDA  GPIOT_21   | :::                | :::          | :::           | 
-''Sensor SCL'' <-> ''I2C0_SCK'' (PIN 22\\ +^  VIM1S    |  I2CM B  |  22(SCL)  |  GPIOD_7    |                  |  1            /dev/i2c-1   | 
-''Sensor SDA'' <-> ''I2C0_SDA'' (PIN 23\\ +| :::       | :::      |  23(SDA)  |  GPIOD_6    | :::                | :::          | :::           | 
-''Sensor GND'' <-> ''GND'' \\ +| :::        I2CM E  |  25(SCL)  |  GPIOZ_11    i2cm_e            |  4           |  /dev/i2c-4   | 
-''Sensor VCC'' <-> ''5V'' or ''3.3V'' %%//%%depends on your sensor \\ +| :::       | :::      |  26(SDA)  |  GPIOZ_12   | :::                | :::          | :::           |
-**I2C 4** \\ +
-''Sensor SCL'' <-> ''I2C1_SCK'' (PIN 25\\ +
-''Sensor SDA'' <-> ''I2C1_SDA'' (PIN 26) \\ +
-''Sensor GND'' <-> ''GND'' \\ +
-''Sensor VCC'' <-> ''5V'' or ''3.3V'' %%//%%depends on your sensor+
  
- +===== Enable I2C =====
-^  I2C    ^  PIN & GPIO Number                                              DT Overlays Node  ^  Bus Number  ^  Device Node  ^ +
-| I2CM A  | SCL - PIN25 - GPIOT_20 (#466)\\ SDA - PIN26 - GPIOT_21 (#467)  |  i2cm_a            |  0            /dev/i2c-0   | +
-| I2CM F  | SCL - PIN22 - GPIOY_17 (#501)\\ SDA - PIN23 - GPIOY_18 (#502)  |  i2cm_f            |  5            /dev/i2c-5   | +
- +
-<tabbox VIM4> +
- +
-^  I2C    ^  PIN & GPIO Number                                              DT Overlays Node  ^  Bus Number  ^  Device Node  ^ +
-| I2CM A  | SCL - PIN25 - GPIOT_20 (#466)\\ SDA - PIN26 - GPIOT_21 (#467)  |  i2cm_a            |  0            /dev/i2c-0   | +
-| I2CM F  | SCL - PIN22 - GPIOY_17 (#501)\\ SDA - PIN23 - GPIOY_18 (#502)  |  i2cm_f            |  5            /dev/i2c-5   | +
- +
-</tabbox> +
- +
-===== Enabel I2C =====+
  
 In order to use the I2C, you need to enable the I2C function via [[products:sbc:common:configurations:device-tree-overlay|Device Tree Overlay]]. In order to use the I2C, you need to enable the I2C function via [[products:sbc:common:configurations:device-tree-overlay|Device Tree Overlay]].
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 <tabbox VIM1/2/3/3L/Edge1> <tabbox VIM1/2/3/3L/Edge1>
  
-Edit ''/boot/env.txt'' to add the i2c node to ''overlays'' node.+Edit ''/boot/env.txt'' to add the i2c node to ''overlays'' node if it doesn't exist.
  
-Take VIM3 as an example to enable ''i2c3'':+Take VIM3 as an example to enable ''I2CM 3'', you need to add ''i2c3'' node to ''overlays'' node if it doesn't exist.
  
 ```shell ```shell
Line 63: Line 45:
 /dev/i2c-3 /dev/i2c-3
 ``` ```
 +
 +<tabbox VIM3 with 5.15 kernel>
 +
 +Edit ''/boot/dtb/amlogic/kvim3.dtb.overlay.env'' to add i2c node to ''fdt_overlays'' node if it doesn't exist.
 +
 +
 +e.g. To enable ''I2CM 3'', you need to add ''i2c3'' to node ''fdt_overlays'' if it doesn't exist.
 +
 +```shell
 +fdt_overlays=i2c3
 +
 +```
 +
 +After reboot, you will see the I2C device node.
 +
 +<tabbox VIM3L with 5.15 kernel>
 +
 +Edit ''/boot/dtb/amlogic/kvim3l.dtb.overlay.env'' to add i2c node to ''fdt_overlays'' node if it doesn't exist.
 +
 +
 +e.g. To enable ''I2CM 3'', you need to add ''i2c3'' to node ''fdt_overlays'' if it doesn't exist.
 +
 +```shell
 +fdt_overlays=i2c3
 +
 +```
 +
 +After reboot, you will see the I2C device node.
  
 <tabbox VIM4> <tabbox VIM4>
  
-Edit ''/boot/dtb/amlogic/kvim4.dtb.overlay.env'' to add i2c node to ''fdt_overlays'' node.+Edit ''/boot/dtb/amlogic/kvim4.dtb.overlay.env'' to add i2c node to ''fdt_overlays'' node if it doesn't exist.
  
  
-e.g. Enable ''I2CM A'', you need to add ''i2cm_a'' to node ''fdt_overlays''.+e.g. To enable ''I2CM A'', you need to add ''i2cm_a'' to node ''fdt_overlays'' if it doesn't exist.
  
 ```shell ```shell
Line 81: Line 91:
 $ ls /dev/i2c-0 $ ls /dev/i2c-0
 /dev/i2c-0 /dev/i2c-0
 +```
 +
 +<tabbox VIM1S>
 +
 +Edit ''/boot/dtb/amlogic/kvim1s.dtb.overlay.env'' to add i2c node to ''fdt_overlays'' node if it doesn't exist.
 +
 +
 +e.g. To enable ''I2CM E'', you need to add ''i2cm_e'' to node ''fdt_overlays'' if it doesn't exist.
 +
 +```shell
 +fdt_overlays=i2cm_e
 +
 +```
 +
 +After reboot, you will see the I2C device node.
 +
 +```shell
 +$ ls /dev/i2c-4
 +/dev/i2c-4
 ``` ```
  
 </tabbox> </tabbox>
 +
 +===== I2C Usage =====
 +
 +Please check the [[https://manpages.ubuntu.com/manpages/jammy/en/man8/i2cdetect.8.html|I2C Usage]].
  
  
 ===== Disable I2C to Use GPIO ===== ===== Disable I2C to Use GPIO =====
  
-If you want to use normal GPIO instead of I2C, you can remove the I2C node in device tree overlays configration file+If you want to use normal GPIO instead of I2C, you can remove the I2C node in [[products:sbc:common:configurations:device-tree-overlay|Device Tree Overlay]]
Last modified: 2022/07/12 04:33 by nick