Robot Cheat Sheet
Print this and tape it to the table. Everything the
robot understands is on this page.
IR remote
Works the moment the robot is switched on. No phone needed.
| ▲ ▼ ◀ ▶ | drive while held |
| OK | STOP — always works |
| 1 / 2 / 3 | run stored program 1 / 2 / 3 |
| 4 | line tracking |
| 5 | obstacle avoidance |
| 6 | follow |
| 7 | light seek |
| 8 | seek (radar lock) |
| 9 | speed up a notch (wraps) |
| 0 | let go of control |
Program language
One instruction per line. Upper or lower case, both fine.
| F 900 | forward for 900 ms |
| B 900 | backward |
| L 350 | spin left |
| R 350 | spin right |
| W 500 | wait, wheels stopped |
| V 5 | speed 0–9 |
| E 90 | point sonar, 0–180° |
| P 4 … Q | repeat 4 times |
| I 5 … Z | if sensor 5 is true |
| X | end the program |
Sensor numbers for I
| 1 | left line sees black |
| 2 | right line sees black |
| 3 | something close on the left |
| 4 | something close on the right |
| 5 | wall closer than 25 cm |
| 6 | the way ahead is clear |
| 7 | the right side is clear |
| 8 | the left side is clear |
6, 7 and 8 are the opposites of 5, 4 and 3. Pair them to
get an if/else.
Typed commands
Same over USB or Bluetooth.
| f b l r s | drive / stop |
| 0–9 | speed (0 is slowest, NOT release) |
| t a w p y | line / avoid / follow / light / seek |
| d | read all sensors once |
| h1 / h0 | live sensor stream on / off |
| *1 *2 *3 | pick program slot |
| [ … ] | save a program into the slot |
| g / k | run / list the slot |
| z z | set servo centre (twice within 6 s) |
| j<n> | straight-drive trim, −15…15 |
When something is wrong
| No servo wiggle at power-on | servo not connected |
| Distance always “clear” | press d: NOECHO climbing means the sonar never answered |
| SAVED steps= is too small | part of the upload was lost; send it again |
| Robot stops by itself | manual driving expires after 0.4 s; hold, do not tap |
| Flashing red banner | battery cutoff — charge before anything else |
| Turns are wrong after a change | re-run calibration; the numbers moved |
Healthy numbers
| 5V rail | 4.90–5.10 V |
| Battery pack (2 cells) | 8.4 V full, 7.0 V get ready, 6.6 V cutoff |
| One room | 30.5 cm (12 inches) |
| Program slots | 3, up to 100 steps each |
