Events

This page documents events sent from the Nimbus CloudWash Payment Panel to the host system.

Overview

The device sends event notifications when user interactions occur. Events use the same command protocol as screen commands but are sent from the device to the host.

Event Structure

Events follow the standard command structure:

Field	Size	Value	Description
type	1 byte	0x21 ('!')	WRITE command
group	1 byte	0x02	EVENTS group
id	1 byte	varies	Event type ID
payload_len	1 byte	varies	Length of payload
payload	variable	—	Event data
crc16	2 bytes	—	CRC16 checksum (little-endian)

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Button Press Event

Event ID: 0x01

The device has 5 physical buttons (B1-B5). This event is sent when any button is pressed.

Structure

Field	Size	Value	Description
type	1 byte	0x21	WRITE
group	1 byte	0x02	EVENTS
id	1 byte	0x01	BUTTON_PRESS
payload_len	1 byte	0x01	1 byte payload
payload	1 byte	0x01-0x05	Button ID
crc16	2 bytes	—	CRC16

Button IDs

ID	Button	Description
0x01	B1	Button 1 (leftmost)
0x02	B2	Button 2
0x03	B3	Button 3 (center)
0x04	B4	Button 4
0x05	B5	Button 5 (rightmost)

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Binary Examples

Button 1 Press Event

Command Structure:
  type:        0x21  (WRITE)
  group:       0x02  (EVENTS)
  id:          0x01  (BUTTON_PRESS)
  payload_len: 0x01  (1 byte)
  payload:     0x01  (Button B1)
  crc16:       0xE5F1 (little-endian: F1 E5)

Binary: 21 02 01 01 01 F1 E5

Button 3 Press Event

Command Structure:
  type:        0x21  (WRITE)
  group:       0x02  (EVENTS)
  id:          0x01  (BUTTON_PRESS)
  payload_len: 0x01  (1 byte)
  payload:     0x03  (Button B3)
  crc16:       0xA5B3 (little-endian: B3 A5)

Binary: 21 02 01 01 03 B3 A5

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Implementation Reference

Event definitions are located in Inc/communication/commands.h under the CMD::EVENTS namespace.

namespace EVENTS {
    static const uint8_t GROUP = 0x02;

    namespace ID {
        static const uint8_t BUTTON_PRESS = 0x01;
    }

    namespace BUTTON {
        static const uint8_t B1 = 1;
        static const uint8_t B2 = 2;
        static const uint8_t B3 = 3;
        static const uint8_t B4 = 4;
        static const uint8_t B5 = 5;
    }
}

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Related Documentation

• Command Protocol - Protocol structure and CRC calculation
• Screens - Available screens and their parameters