259 KIBO Leak-Inspection Target Controller (VGA)
259 : KIBO Leak-Inspection Target Controller (VGA)
- Author: Your Name
- Description: 8-state leak-inspection approach/align/inspect FSM with a live 640x480 VGA status display and a latched safety abort.
- GitHub repository
- Open in 3D viewer
- Open in Tiny Tapeout Explorer
- Open in VGA Playground
- Clock: 25175000 Hz
How it works
An FSM controls an inspection robot (modelled on Int-Ball2 / Kibo-RPC) as it approaches a suspected leak-inspection target, and a VGA generator draws its live status on a 640x480 @ 60 Hz display (Tiny VGA PMOD on uo, 25.175 MHz clock).
States (also on uio[2:0]):
| Code | State | Behaviour |
|---|---|---|
| 000 | IDLE | Waits for target_detected |
| 001 | SEARCH | Waits for target_detected to confirm a target |
| 010 | APPROACH | move_cmd = FORWARD until target_reached |
| 011 | ALIGN | Corrects position and orientation until both are aligned |
| 100 | HOLD | Holds for 3 FSM steps |
| 101 | INSPECT | inspect_enable = 1 until inspection_done |
| 110 | COMPLETE | target_locked = 1; new_target -> SEARCH, else IDLE |
| 111 | ABORT | abort_cmd = 1, all motion stopped, latched until reset |
The FSM takes one step every 16 video frames (about 0.27 s) so it is easy to watch. system_fault or obstacle_detected is checked on every clock and sends the FSM to ABORT immediately from any state, ahead of every other input. Inputs are passed through a 2-flip-flop synchroniser.
Display layout
Each row is 64 px tall, cells are 64 px wide starting at x = 64. Lit cells are coloured, unlit cells are dark grey.
| Row | Content |
|---|---|
| 0 | Banner in the current state's colour (blinks dark/red in ABORT) |
| 1 | 8 state boxes, left to right: IDLE, SEARCH, APPROACH, ALIGN, HOLD, INSPECT, COMPLETE, ABORT |
| 2 | The 8 input flags, left to right: ui[0]..ui[7] (obstacle and fault light red) |
| 3 | move_cmd, left to right: STOP (white), FORWARD, BACKWARD, LEFT, RIGHT, UP, DOWN |
| 4 | align_cmd, left to right: none, rotate left, rotate right, aligned (green) |
| 5 | Lamps: inspect_enable (magenta), target_locked (green), abort_cmd (red) |
| 6 | Mission progress bar (cyan), green when COMPLETE, solid red in ABORT |
State colours: IDLE grey, SEARCH light blue, APPROACH blue, ALIGN yellow, HOLD orange, INSPECT magenta, COMPLETE green, ABORT red.
move_cmd and align_cmd appear only on the display. The other command outputs are on uio[5:3].
How to test
- Connect a Tiny VGA PMOD to the
uoconnector and a monitor. Set the clock to 25.175 MHz. - Pulse
rst_nlow then high. The IDLE box lights. - Set
ui[0](target_detected): the FSM moves to APPROACH. - Set
ui[1]: ALIGN. Setui[2]andui[3]: HOLD, then INSPECT. - Set
ui[4]: COMPLETE, then IDLE (or SEARCH ifui[7]is set). - Set
ui[5]orui[6]at any time to see ABORT. Only reset clears it.
For simulation, set uio[7] high so the FSM steps every clock instead of every 16 frames.
External hardware
Tiny VGA PMOD (or any 2-bit-per-channel VGA DAC with the same pin order) and a VGA monitor. Switches on ui and, optionally, LEDs on uio[5:0].
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | target_detected | R1 | state[0] |
| 1 | target_reached | G1 | state[1] |
| 2 | position_aligned | B1 | state[2] |
| 3 | orientation_aligned | vsync | inspect_enable |
| 4 | inspection_done | R0 | abort_cmd |
| 5 | obstacle_detected | G0 | target_locked |
| 6 | system_fault | B0 | |
| 7 | new_target | hsync | fast_step (1 = step every clock, for simulation) |