Overview¶

This program is an example program that uses the FRDM-TFC library to actually permit a car using the FDRM-TFC shield + FRDM-KL25Z to race around a center line track.

Car Hookup¶

Motors

• Code written assuming left motor hooked to B1(red)/B2(black) and right motor hooked to A1(red)/A2(black).

Battery

• Be sure to hook positive (red) to 'Vbat' and negative (black) to 'Gnd'

Steering Servo

• Servo must be hooked up with black wire innermost (away from LEDs).
• Also be sure to mount servo on chassis with wire coming out the right side of the car.

Camera

• Camera must be hooked up with black wire towards LEDs on the shield board.
• Be sure to mount camera on tower with connector down towards the bottom.

Potentiometers (Pots)

• Pots by default should have arrows pointing toward battery/motor hookup (for demo mods default).

Car Hardware Controls¶

DIP SWITCH CONTROLS:

• Switch 1: Controls whether running main racing program (ON) or Demo program (OFF). Function of other 3 switches depend on this first switch.

RACING MODE (Switch 1 = ON)

• Switch 2: Logging frame camera data to RAM while racing. Enable (ON) or Disable (OFF).
• Switch 3: Risky / faster racing (ON); Conservative / slower race option (OFF). NOTE: Faster mode may cause car to fall off track. Needs tweaking...
• Switch 4: Enable Start Gate Stop (ON) or Disable (OFF). NOTE: May not actually stop at start gate. Needs tweaking...
• POTs 1,2 - controls nothing at the moment
• PUSHBUTTON A - START car race!
• PUSHBUTTON B - END CAR RACE / (while holding down when 'log frame data' active will also output terminal data gathered during race)

• LEDs 1,2 light when Track is found
• LEDs 0,3 light when Start Gate is Found

DEMO MODE 0 (Switch 1 = OFF; Switch 2 = OFF, Switch 3 = OFF)

• PUSHBUTTON A - Light LED 0
• PUSHBUTTON B - Light LED 3

DEMO MODE 1 (Switch 1 = OFF; Switch 2 = ON, Switch 3 = OFF)

• POT 1 - Controls Servo: CCW = left; CW = right

DEMO MODE 2 (Switch 1 = OFF; Switch 2 = OFF, Switch 3 = ON)

• POT 1 - Controls speed of right wheel: CCW = reverse; CW = forward
• POT 2 - Controls speed of left wheel: CCW = reverse; CW = forward
• NOTE In this mode the high pitched whine heard is of the H-bridge being active. To disable whine, briefly put into demo mode 1 above.

DEMO MODE 3 (Switch 1 = OFF; Switch 2 = ON, Switch 3 = ON)

• Outputs camera data captured to terminal in CSV format, once every second.

Car Calibration¶

Camera

• Be sure to focus the camera properly

Servo/Steering

More Info¶

• The Freescale Cup main info page
• redxeth youtube channel with useful related videos