Example 3B: Command Script Flowing Light

Experiment Overview

Use FastBee's Command Script Action (actionType=15) to create LED flowing-light effects through a small declarative sequence of PERIPH, DELAY, and LOG commands.

Hardware Wiring

Board Label	GPIO Pin	Connected Device
D1	GPIO15	LED1 (active-low)
D2	GPIO2	LED2 (active-low)
D3	GPIO0	LED3 (active-low)
D4	GPIO4	LED4 (active-low)

Method 1: Basic Sequential Flowing Light

Peripheral Execution Rule Configuration

json

{
  "id": "rule_cmd_flow_basic",
  "name": "Command Script - Basic Flowing Light",
  "enabled": false,
  "triggers": [
    { "triggerType": 1, "timerMode": 0, "intervalSec": 3600 }
  ],
  "actions": [
    {
      "targetPeriphId": "",
      "actionType": 15,
      "actionValue": "PERIPH cmd_led1 LOW\nDELAY 300\nPERIPH cmd_led1 HIGH\nPERIPH cmd_led2 LOW\nDELAY 300\nPERIPH cmd_led2 HIGH\nPERIPH cmd_led3 LOW\nDELAY 300\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led4 LOW\nDELAY 300\nPERIPH cmd_led4 HIGH\nLOG Basic flowing light cycle complete",
      "useReceivedValue": false,
      "syncDelayMs": 0,
      "execMode": 0
    }
  ],
  "protocolType": 0,
  "scriptContent": "",
  "reportAfterExec": false
}

Command Script Breakdown

PERIPH cmd_led1 LOW      # Turn on LED1 (active-low)
DELAY 300                # Delay 300ms
PERIPH cmd_led1 HIGH     # Turn off LED1 (active-high)
PERIPH cmd_led2 LOW      # Turn on LED2
DELAY 300                # Delay 300ms
PERIPH cmd_led2 HIGH     # Turn off LED2
... (repeat sequentially)
LOG Basic flowing light cycle complete    # Print log

Execution Methods

Manual Run: Keep the rule disabled and click Run Once in the Web interface. The disabled timer is only a valid placeholder because the current schema has no manual trigger type.
API Call: POST /api/periph-exec/run with form field id=rule_cmd_flow_basic

Method 2: Timer Auto-Cycle Flowing Light

Peripheral Execution Rule Configuration

json

{
  "id": "rule_cmd_flow_timer",
  "name": "Command Script - Timer Cycle Flowing Light",
  "enabled": true,
  "triggers": [
    { "triggerType": 1, "timerMode": 0, "intervalSec": 5 }
  ],
  "actions": [
    {
      "targetPeriphId": "",
      "actionType": 15,
      "actionValue": "PERIPH cmd_led1 LOW\nDELAY 300\nPERIPH cmd_led1 HIGH\nPERIPH cmd_led2 LOW\nDELAY 300\nPERIPH cmd_led2 HIGH\nPERIPH cmd_led3 LOW\nDELAY 300\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led4 LOW\nDELAY 300\nPERIPH cmd_led4 HIGH",
      "useReceivedValue": false,
      "syncDelayMs": 0,
      "execMode": 0
    }
  ],
  "protocolType": 0,
  "scriptContent": "",
  "reportAfterExec": false
}

Configuration Notes

intervalSec: 5 - Execute one cycle every 5 seconds; the script's four 300 ms delays control the LED timing
No manual trigger needed; runs automatically after system startup

Method 3: Bidirectional Flowing Light

Peripheral Execution Rule Configuration

json

{
  "id": "rule_cmd_flow_bidirectional",
  "name": "Command Script - Bidirectional Flowing Light",
  "enabled": true,
  "triggers": [
    { "triggerType": 1, "timerMode": 0, "intervalSec": 5 }
  ],
  "actions": [
    {
      "targetPeriphId": "",
      "actionType": 15,
      "actionValue": "PERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nPERIPH cmd_led2 LOW\nDELAY 200\nPERIPH cmd_led2 HIGH\nPERIPH cmd_led3 LOW\nDELAY 200\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led4 LOW\nDELAY 200\nPERIPH cmd_led4 HIGH\nPERIPH cmd_led3 LOW\nDELAY 200\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led2 LOW\nDELAY 200\nPERIPH cmd_led2 HIGH",
      "useReceivedValue": false,
      "syncDelayMs": 0,
      "execMode": 0
    }
  ],
  "protocolType": 0,
  "scriptContent": "",
  "reportAfterExec": false
}

Execution Sequence

LED1 → LED2 → LED3 → LED4 → LED3 → LED2 → (cycle)

Achieves a "ping-pong" back-and-forth effect.

Method 4: Accumulative Brightening Flowing Light

Peripheral Execution Rule Configuration

json

{
  "id": "rule_cmd_flow_accumulate",
  "name": "Command Script - Accumulative Flowing Light",
  "enabled": true,
  "triggers": [
    { "triggerType": 1, "timerMode": 0, "intervalSec": 5 }
  ],
  "actions": [
    {
      "targetPeriphId": "",
      "actionType": 15,
      "actionValue": "PERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led2 LOW\nDELAY 200\nPERIPH cmd_led3 LOW\nDELAY 200\nPERIPH cmd_led4 LOW\nDELAY 500\nPERIPH cmd_led1 HIGH\nPERIPH cmd_led2 HIGH\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led4 HIGH",
      "useReceivedValue": false,
      "syncDelayMs": 0,
      "execMode": 0
    }
  ],
  "protocolType": 0,
  "scriptContent": "",
  "reportAfterExec": false
}

Effect Description

LEDs turn on sequentially without turning off
After all 4 LEDs are on, delay 500ms
Then all turn off, start next cycle

Method 5: Random MQTT Telemetry (with LEDs Reset)

Peripheral Execution Rule Configuration

json

{
  "id": "rule_cmd_flow_random",
  "name": "Command Script - Random Flowing Light",
  "enabled": true,
  "triggers": [
    { "triggerType": 1, "timerMode": 0, "intervalSec": 5 }
  ],
  "actions": [
    {
      "targetPeriphId": "",
      "actionType": 15,
      "actionValue": "PERIPH cmd_led1 HIGH\nPERIPH cmd_led2 HIGH\nPERIPH cmd_led3 HIGH\nPERIPH cmd_led4 HIGH\nMQTT 0 [{\"id\":\"flow_state\",\"value\":\"RANDOM(1,4)\"}]\nLOG Random flowing light triggered",
      "useReceivedValue": false,
      "syncDelayMs": 0,
      "execMode": 0
    }
  ],
  "protocolType": 0,
  "scriptContent": "",
  "reportAfterExec": false
}

Description

Resets all four LEDs to HIGH, then uses RANDOM(1,4) in the MQTT payload
RANDOM() expansion is supported in MQTT and LOG commands; it does not dynamically rewrite peripheral IDs
Requires the MQTT feature to be active and connected; otherwise the MQTT command is skipped

Command Script Syntax Reference

Supported Commands

Command	Format	Description
PERIPH	`PERIPH <id> <action> [value]`	Control peripheral
DELAY	`DELAY <ms>`	Delay (milliseconds)
LOG	`LOG <message>`	Print log
MQTT	`MQTT <topicIndex> <payload>`	Publish through a configured MQTT topic by zero-based index

PERIPH Sub-commands

Sub-command	Format	Description
HIGH	`PERIPH <id> HIGH`	Output HIGH
LOW	`PERIPH <id> LOW`	Output LOW
PWM	`PERIPH <id> PWM <value>`	Set 8-bit PWM duty (0-255)
BLINK	`PERIPH <id> BLINK <interval_ms>`	Blink
BREATHE	`PERIPH <id> BREATHE <cycle_ms>`	Start breathing effect
STOP	`PERIPH <id> STOP`	Stop the target's active effect

Command Separator

Use \n (newline) to separate multiple commands
Must be escaped as \\n in JSON

Capability Boundary

Command scripts are designed for short, deterministic sequences. They do not provide variables, conditions, or loops. Use rule triggers and multiple actions for conditions and linkage; use a timer trigger to repeat a sequence.

Notes

Command Length Limit: One command script is limited to 1024 characters and 50 commands
DELAY Accuracy: Actual delay may have ±10ms error
GPIO0 Limitation: Do not pull GPIO0 LOW during boot, otherwise enters download mode
Delay Limit: A single DELAY is limited to 10 seconds and total delay to 30 seconds; execution times out after 35 seconds
Trigger Frequency: Timer interval should be greater than total script execution time to avoid queue buildup
Log Output: Use LOG command to track script execution progress for debugging
Error Handling: If peripheral ID in PERIPH command does not exist, it will be skipped and execution continues

Extended Exercises

Exercise 1: Breathing Light Effect

Use PWM commands to achieve LED breathing effect:

json

{
  "actionValue": "PERIPH cmd_led1 PWM 0\nDELAY 50\nPERIPH cmd_led1 PWM 512\nDELAY 50\nPERIPH cmd_led1 PWM 1024\nDELAY 50\nPERIPH cmd_led1 PWM 2048\nDELAY 50\nPERIPH cmd_led1 PWM 4095\nDELAY 50\nPERIPH cmd_led1 PWM 2048\nDELAY 50\nPERIPH cmd_led1 PWM 1024\nDELAY 50\nPERIPH cmd_led1 PWM 512\nDELAY 50\nPERIPH cmd_led1 PWM 0"
}

Exercise 2: Traffic Light Simulation

Use 3 LEDs to simulate red/yellow/green traffic light:

json

{
  "actionValue": "PERIPH led_red LOW\nDELAY 3000\nPERIPH led_red HIGH\nPERIPH led_yellow LOW\nDELAY 1000\nPERIPH led_yellow HIGH\nPERIPH led_green LOW\nDELAY 3000\nPERIPH led_green HIGH\nLOG Traffic light cycle complete"
}

Exercise 3: Morse Code

Use LED to send SOS signal:

json

{
  "actionValue": "PERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nDELAY 200\nPERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nDELAY 200\nPERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nDELAY 600\nPERIPH cmd_led1 LOW\nDELAY 600\nPERIPH cmd_led1 HIGH\nDELAY 600\nPERIPH cmd_led1 LOW\nDELAY 600\nPERIPH cmd_led1 HIGH\nDELAY 600\nPERIPH cmd_led1 LOW\nDELAY 600\nPERIPH cmd_led1 HIGH\nDELAY 600\nPERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nDELAY 200\nPERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nDELAY 200\nPERIPH cmd_led1 LOW\nDELAY 200\nPERIPH cmd_led1 HIGH\nLOG SOS complete"
}

Tip: Save hardware-control rules as disabled first, run them once for verification, and only then enable their timer or event trigger.

Example 3B: Command Script Flowing Light ​

Experiment Overview ​

Hardware Wiring ​

Method 1: Basic Sequential Flowing Light ​

Peripheral Execution Rule Configuration ​

Command Script Breakdown ​

Execution Methods ​

Method 2: Timer Auto-Cycle Flowing Light ​

Peripheral Execution Rule Configuration ​

Configuration Notes ​

Method 3: Bidirectional Flowing Light ​

Peripheral Execution Rule Configuration ​

Execution Sequence ​

Method 4: Accumulative Brightening Flowing Light ​

Peripheral Execution Rule Configuration ​

Effect Description ​

Method 5: Random MQTT Telemetry (with LEDs Reset) ​

Peripheral Execution Rule Configuration ​

Description ​

Command Script Syntax Reference ​

Supported Commands ​

PERIPH Sub-commands ​

Command Separator ​

Capability Boundary ​

Notes ​

Extended Exercises ​

Exercise 1: Breathing Light Effect ​

Exercise 2: Traffic Light Simulation ​

Exercise 3: Morse Code ​

Related Documents ​

Example 3B: Command Script Flowing Light

Experiment Overview

Hardware Wiring

Method 1: Basic Sequential Flowing Light

Peripheral Execution Rule Configuration

Command Script Breakdown

Execution Methods

Method 2: Timer Auto-Cycle Flowing Light

Peripheral Execution Rule Configuration

Configuration Notes

Method 3: Bidirectional Flowing Light

Peripheral Execution Rule Configuration

Execution Sequence

Method 4: Accumulative Brightening Flowing Light

Peripheral Execution Rule Configuration

Effect Description

Method 5: Random MQTT Telemetry (with LEDs Reset)

Peripheral Execution Rule Configuration

Description

Command Script Syntax Reference

Supported Commands

PERIPH Sub-commands

Command Separator

Capability Boundary

Notes

Extended Exercises

Exercise 1: Breathing Light Effect

Exercise 2: Traffic Light Simulation

Exercise 3: Morse Code

Related Documents