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=Flexbot PCBs=

==Teensy board==

[[File:leg_teensy_annotated.png |700px]]

Figure 1. Plug names and pin allocation for Teensy board.
* IMU0, on-board, SCL0, pin 18-19, AD0=NC, Knee.
* IMU1, SCL1, pin 37_38-19, AD0=HIGH, Thigh (upper leg).
* IMU2, SCL1, pin 37_38-19, AD0=NC, Shin (lower leg).
* IMU3, SCL2, pin 3_4, AD0 = HIGH, Foot.
* IMU4, SCL2, pin 3_4, AD0 = NC, Hip.

===Actuators===
====Steering====
* 1: 12V, 
* 2: PWM pin 5 - moved to pin 29 (timer FTM2 200 Hz?), 
* 3:pot pin 23 (A9), 
* 4: GND

====Actuator 1 - upper leg====
motor
* 1: (5V) nc.
* 2: PWM pin 21 (timer FMT3)
* 3: direction pin 26
* 4: GND
encoder
* 1: 5V
* 2: A pin 39
* 3: B pin 30 - patched from A21 DAC0)
* 4: GND
current sensor
* 1: 5V
* 2: sense pin 16 (A2)
* 3: gnd

====Actuator 2 - lower leg====
Motor
* 1: direction pin 25
* 2: PWM pin 22 (timer FMT0)
* 3: GND
encoder
* 1: 5V
* 2: A pin 5 - patched from A22/DAC1
* 3: B pin 36
* 4: GND
current sensor
* 1: 5V
* 2: sense pin 15 (A1)
* 3: gnd
====Wheel====
motor driver
* 1: nc (s2 not connected)
* 2: PWM pin 2 (timer FTM3) (S1) (RC mode 200 Hz?)
* 3: GND - NB! connected to motor power GND (probably OK to connect)
encoder
* 1: 5V
* 2: A pin 35
* 3: B pin 34
* 4: GND
current
* 1: 5V
* 2: sense pin 17 (A3)
* 3: GND

==Cables in leg==

[[File:cables-in-leg.png |700px]]

Figure 2. Overview of cables in one leg with some wire details. The connection to robot base platform is 24V (10A) and USB only.
Steering servo should be in RC servo interface mode.

Wheel motor driver in RC mode: switch 1=off, all others ON. S1 used only.

==Controller block diagram==


[[File:leg_teensy-block-function.png | 700px]]

Figure 3. Functional blockdiagram og Teensy controller board. Not all blocks and MAV messages are implemented yet.

==Teensy board and schematic==

[[File:leg_teensy_board.png | 600px]]

Figure 4. Layout of PCB (designed in Eagle).



[[File:leg_teensy_schematic.png | 500px]]

Figure 5. PCB schematic - click on image to get better view.

[[File:teensy_board_patches_annotated.png | 500px]]

Figure 6. Needed patches. PWM for steering servo in RC mode now moved to timer FMT3 on pin 29 (old connection to pin 5 must be cut). Actuator 1 encoder A also connected to pin 5 (for interrupt), and actuator 2 encoder B also connected to (free) pin 30 - also for interrupt. The last 2 maintains connection to DAC pins and pull-up resistors.