mpu9250: add MPU6500 (#5767)

Signed-off-by: Yifei Ding <yifeiding@protonmail.com>

4 files changed, 92 insertions, 14 deletions

diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md
index 2df6ddf5..4319a056 100644
--- a/docs/Config_Reference.md
+++ b/docs/Config_Reference.md
@@ -1640,13 +1640,14 @@ cs_pin:
 
 ### [mpu9250]
 
-Support for mpu9250 and mpu6050 accelerometers (one may define any
-number of sections with an "mpu9250" prefix).
+Support for MPU-9250, MPU-9255, MPU-9255, MPU-6050, and MPU-6500
+accelerometers (one may define any number of sections with an
+"mpu9250" prefix).
 
 ```
 [mpu9250 my_accelerometer]
 #i2c_address:
-#   Default is 104 (0x68).
+#   Default is 104 (0x68). If AD0 is high, it would be 0x69 instead.
 #i2c_mcu:
 #i2c_bus:
 #i2c_speed: 400000
diff --git a/docs/Measuring_Resonances.md b/docs/Measuring_Resonances.md
index 7f41bd4d..ba9ad3e9 100644
--- a/docs/Measuring_Resonances.md
+++ b/docs/Measuring_Resonances.md
@@ -18,6 +18,31 @@ that it has a voltage regulator and a level shifter.
 
 ### Wiring
 
+An ethernet cable with shielded twisted pairs (cat5e or better) is recommended
+for signal integrety over a long distance. If you still experience signal integrity
+issues (SPI/I2C errors), shorten the cable.
+
+Connect ethernet cable shielding to the controller board/RPI ground.
+
+***Double-check your wiring before powering up to prevent
+damaging your MCU/Raspberry Pi or the accelerometer.***
+
+#### SPI Accelerometers
+
+Suggested twisted pair order:
+
+```
+GND+MISO
+3.3V+MOSI
+SCLK+CS
+```
+
+##### ADXL345
+
+
+**Note: Many MCUs will work with an ADXL345 in SPI mode(eg Pi Pico), wiring and
+configuration will vary according to your specific board and avaliable pins.**
+
 You need to connect ADXL345 to your Raspberry Pi via SPI. Note that the I2C
 connection, which is suggested by ADXL345 documentation, has too low throughput
 and **will not work**. The recommended connection scheme:
@@ -31,25 +56,46 @@ and **will not work**. The recommended connection scheme:
 | SDA | 19 | GPIO10 (SPI0_MOSI) |
 | SCL | 23 | GPIO11 (SPI0_SCLK) |
 
-An alternative to the ADXL345 is the MPU-9250 (or MPU-6050).  This
-accelerometer has been tested to work over I2C on the RPi at 400kbaud.
-Recommended connection scheme for I2C:
+Fritzing wiring diagrams for some of the ADXL345 boards:
+
+![ADXL345-Rpi](img/adxl345-fritzing.png)
+
+#### I2C Accelerometers
+
+Suggested twisted pair order:
+
+```
+3.3V+SDA
+GND+SCL
+```
+
+##### MPU-9250/MPU-9255/MPU-6515/MPU-6050/MPU-6500
+
+Alternatives to the ADXL345 are MPU-9250/MPU-9255/MPU-6515/MPU-6050/MPU-6500.
+These accelerometers have been tested to work over I2C on the RPi or RP2040(pico)
+at 400kbaud.
+
+Recommended connection scheme for I2C on the Raspberry Pi:
 
 | MPU-9250 pin | RPi pin | RPi pin name |
 |:--:|:--:|:--:|
-| 3V3 (or VCC) | 01 | 3.3v DC power |
+| VCC | 01 | 3.3v DC power |
 | GND | 09 | Ground |
 | SDA | 03 | GPIO02 (SDA1) |
 | SCL | 05 | GPIO03 (SCL1) |
 
+![MPU-9250 connected to RPI](img/mpu9250-PI-fritzing.png)
 
-Fritzing wiring diagrams for some of the ADXL345 boards:
-
-![ADXL345-Rpi](img/adxl345-fritzing.png)
+Recommended connection scheme for I2C(i2c0a) on the RP2040:
 
+| MPU-9250 pin | RP2040 pin | RPi pin name |
+|:--:|:--:|:--:|
+| VCC | 39 | 3v3 |
+| GND | 38 | Ground |
+| SDA | 01 | GP0 (I2C0 SDA) |
+| SCL | 02 | GP1 (I2C0 SCL) |
 
-Double-check your wiring before powering up the Raspberry Pi to prevent
-damaging it or the accelerometer.
+![MPU-9250 connected to PICO](img/mpu9250-PICO-fritzing.png)
 
 ### Mounting the accelerometer
 
@@ -96,10 +142,13 @@ Afterwards, check and follow the instructions in the
 [RPi Microcontroller document](RPi_microcontroller.md) to setup the
 "linux mcu" on the Raspberry Pi.
 
+#### Configure ADXL345 With RPi
+
 Make sure the Linux SPI driver is enabled by running `sudo
 raspi-config` and enabling SPI under the "Interfacing options" menu.
 
-For the ADXL345, add the following to the printer.cfg file:
+Add the following to the printer.cfg file:
+
 ```
 [mcu rpi]
 serial: /tmp/klipper_host_mcu
@@ -115,9 +164,12 @@ probe_points:
 It is advised to start with 1 probe point, in the middle of the print bed,
 slightly above it.
 
-For the MPU-9250, make sure the Linux I2C driver is enabled and the baud rate is
+#### Configure MPU-6000/9000 series With RPi
+
+Make sure the Linux I2C driver is enabled and the baud rate is
 set to 400000 (see [Enabling I2C](RPi_microcontroller.md#optional-enabling-i2c)
 section for more details). Then, add the following to the printer.cfg:
+
 ```
 [mcu rpi]
 serial: /tmp/klipper_host_mcu
@@ -132,6 +184,28 @@ probe_points:
     100, 100, 20  # an example
 ```
 
+#### Configure MPU-6000/9000 series With PICO
+
+PICO I2C is set to 400000 on default. Simply add the following to the
+printer.cfg:
+
+```
+[mcu pico]
+serial: /dev/serial/by-id/<your PICO's serial ID>
+
+[mpu9250]
+i2c_mcu: pico
+i2c_bus: i2c1a
+
+[resonance_tester]
+accel_chip: mpu9250
+probe_points:
+    100, 100, 20  # an example
+
+[static_digital_output pico_3V3pwm] # Improve power stability
+pin: pico:gpio23
+```
+
 Restart Klipper via the `RESTART` command.
 
 ## Measuring the resonances
@@ -158,6 +232,9 @@ is some other ID, it is indicative of the connection problem with ADXL345,
 or the faulty sensor. Double-check the power, the wiring (that it matches
 the schematics, no wire is broken or loose, etc.), and soldering quality.
 
+**If you are using MPU-6000/9000 series accelerometer and it show up as `mpu-unknown`, use with
+caution! They are probably refurbished chips!**
+
 Next, try running `MEASURE_AXES_NOISE` in Octoprint, you should get some
 baseline numbers for the noise of accelerometer on the axes (should be
 somewhere in the range of ~1-100). Too high axes noise (e.g. 1000 and more)
diff --git a/docs/img/mpu9250-PI-fritzing.png b/docs/img/mpu9250-PI-fritzing.png
new file mode 100644
index 00000000..4a48bb06
--- /dev/null
+++ b/docs/img/mpu9250-PI-fritzing.png
diff --git a/docs/img/mpu9250-PICO-fritzing.png b/docs/img/mpu9250-PICO-fritzing.png
new file mode 100644
index 00000000..31919ca1
--- /dev/null
+++ b/docs/img/mpu9250-PICO-fritzing.png