VisualHMI alarm record: trigger conditions, level filtering, buzzer and backlight linkage

The alarm system supportscustom trigger conditions and content entries: It monitors register value changes in real-time and triggers multi-dimensional responses (buzzer, backlight on) when the preset logic is met. Alarm records are persisted across power loss, allowing for traceable auditing.

1. Core function

• Trigger conditions: Set boolean/numeric conditions based on register values (4x1000, M200): ==, !=, >, <, >=, <=, bit status (LW100.3==1)
• Multimodal prompts: Buzzer sounds (tone/duration configurable), screen backlight flashes/highlights the entire screen
• Power-loss storage: Alarm events (including time, content) are automatically stored and retained across power loss and restarts

System register:

2. Alarm Settings (Engineering → Engineering Settings → Alarm Settings)

• Number of Alarms: Maximum 10,000 entries, automatically numbered (Alarm ID) upon point update. Default: 32 entries (IDs 0~31)
• Backlight: Illuminates the backlight when an alarm is triggered (SysWarnCfg bit0), typically used in conjunction with automatic standby
• Buzzer: Off/Beep/Continuous Beep, duration in ms (SysWarnCfg bits 1~2)
• Maximum Record Count: 10,000 entries
• Storage Method: Internal RAM (lost upon power loss) / Dedicated Flash (2,000 entries) / Specified Flash (limited by remaining space). Flash 16M, block size 4K, default block address 2048 (starting from 8M)

Alarm Content Configuration:

• Trigger conditions: >, =, <=, ==, !=, IN (a<=x<=b), OUT;.Reference bit (LW1000.1),~Bit range (LW1000.4~6)
• Alarm level: 0~15 levels, filtered using SysWarnLevel (LW0115) bits 0~15 (e.g., for levels 1+2: SysWarnLevel = (1<<1)|(1<<2))
• Alarm content: Display when condition is met; for multiple languages, edit separately

Clear and export: SysWarnCtrl (LW0114) writes 0x0055 to clear, 0x0001 to export. Alarm content can be imported and exported as CSV (alarm condition, language 1..N, level).

3. Alarm bar/alarm display control

3.1 Alarm Bar (Marquee)

All current alarms are displayed scrolling from left to right. Attributes: Alarm Sorting (Chronological/Reverse Chronological), Alarm Time (Hidden/Time/Date/Time + Date, default is to display only content), Scroll Speed (ms).

3.2 Alarm Display (Table)

Alarm Mode:Current Alarms(Not displayed after being cleared, does not support power-down storage) /Historical Alarms(Retained after being cleared, supports power-down storage). Time Sorting, Display Sequence Number, Occurrence Time/Clearance Time (Hidden/Time/Date/Time + Date), Time First, Column Width Ratio, Lines Per Page, Scroll Bar, Gesture Slide, Page Turn Control (Addr+0 Page Turn, Addr+1 Feasibility).

4. Application Cases

4.1 Alarm Setting Example

Alarm ID0: LW1001==1, Level 1, Content "Alarm 1"; ID1: LW1002.0==1, Level 2, "Alarm 2"; ID2: LW1003.0~3==15, Level 3, "Alarm 3".

4.2 Alarm Bar + Alarm Display + Page Turn + Clear Export

Alarm bar: Chronological order, display date + time, speed 100. Alarm display: Historical alarms, chronological order, both occurrence/clearance time displayed, time first, column width 20;LW1100The page turning button is bound to LW1100 (1/2/3/4) + permission LW1100.1/.2; the clear/export button is bound to LW1100 write 85/1.

4.3 Alarm level filtering + alarm prompt

Pull-down menu binding$SysWarnLevelText: "All; Level 1; Level 2; Level 3", numerical conversion 14; $SysWarnCfg.1~2Select "Buzzer" to turn it off; it will beep twice; then it will beep continuously.

Compiled from the "Alarm Record" tutorial documented in the VisualHMI development document of Guangzhou Dacai Technology (hmi-doc.gz-dc.com), with copyright reserved by Dacai Technology.