doc: Update telemetry.txt

Add a bunch of new packet formats. Document ADC data mapping

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/doc/telemetry.txt b/doc/telemetry.txt
index 7ee0ab3c831abb6a302c1748622ec3de01649075..324c051d1c17605943be5c1210fe5f0c6f4ce98e 100644 (file)
--- a/doc/telemetry.txt
+++ b/doc/telemetry.txt
@@ -102,8 +102,12 @@ Keith Packard <keithp@keithp.com>; Bdale Garbee <bdale@gag.com>
                [options="border",cols="1,3"]
                |====
                |Type   |Description
-               |0x08   |TeleMega IMU Sensor Data
-               |0x09   |TeleMega Kalman and Voltage Data
+               |0x08   |TeleMega IMU Sensor Data with Invensense IMU
+               |0x12   |TeleMega IMU Sensor Data with BMX160 IMU
+               |0x13   |TeleMega IMU Sensor Data with MPU6000 and MMC5983
+               |0x14   |TeleMega IMU Sensor Data with BMI088 and MMC5983
+               |0x09   |TeleMega Kalman and Voltage Data for 15V boards
+               |0x15   |TeleMega Kalman and Voltage data for 30V boards
                |====
 
                TeleMega has a lot of sensors, and so it splits the sensor
@@ -135,6 +139,20 @@ Keith Packard <keithp@keithp.com>; Bdale Garbee <bdale@gag.com>
                from the 3 axis gyroscope to compute the total orientation
                change of the airframe since liftoff.
 
+               Voltage values are reported as raw ADC values, so you
+               need to know the voltage divider in front of the ADC
+               as well as the ADC range.  Boards with a 15 volt range
+               use 100k/27k divider, boards with a 30 volt range use
+               100k/12k. All Mega boards have a 12 bit ADC so the
+               values range from 0 to 4095, and they all use a 3.3V
+               reference, so an ADC value of 0 represents 0V and an
+               ADC value of 4095 represents 3.3V. In sum, to convert
+               a raw ADC value to a voltage, take the value, divide
+               by 4095, multiply by 3.3 then multiply by (adc_hi +
+               adc_lo)/adc_lo, where adc_hi is 100k for both ranges
+               and adc_lo is 27k for 15V boards and 12k for 30V
+               boards.
+
                .TeleMega IMU Sensor Packet Contents
                [options="border",cols="2,3,3,9"]
                |====
@@ -146,9 +164,9 @@ Keith Packard <keithp@keithp.com>; Bdale Garbee <bdale@gag.com>
                |14     |int16_t        |accel_x        |X axis acceleration (across)
                |16     |int16_t        |accel_y        |Y axis acceleration (along)
                |18     |int16_t        |accel_z        |Z axis acceleration (through)
-               |20     |int16_t        |gyro_x         |X axis rotation (across)
-               |22     |int16_t        |gyro_y         |Y axis rotation (along)
-               |24     |int16_t        |gyro_z         |Z axis rotation (through)
+               |20     |int16_t        |gyro_x         |X axis rotation (roll)
+               |22     |int16_t        |gyro_y         |Y axis rotation (pitch)
+               |24     |int16_t        |gyro_z         |Z axis rotation (yaw)
                |26     |int16_t        |mag_x          |X field strength (across)
                |28     |int16_t        |mag_y          |Y field strength (along)
                |30     |int16_t        |mag_z          |Z field strength (through)