Communication DMA-20 ↔ STG-570
Overview
The communication between STG-570 and DMA-20 is made via a CAN bus with a baud rate of 250 kBit/s.
The internal filter will not process CAN messages that do not have the ID 0x7FD.
Pressing a displayed button causes a CAN message to be sent to ID 0x7FC.
Template 0 - Intro Screen
This screen is displayed after power on until a CAN message with the ID 0x7FD is received.
Show Template
CAN-ID: 0x7FD
DLC: 8 Byte
| Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 |
U8 Template number 0x00 | 0x00 | 0x00 | 0x00 | 0x00 | 0x00 | 0x00 | 0x00 |
Template 5 - “Keyboard”
Show Template
CAN-ID:0x7FD
DLC: 8 Byte
Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 |
U8 Template number 0x05 | I32 Value 0 … 2147483647 | U8 Decimal Places 0: 0 1: 1 2: 2 3: 3 4: 4 | not used 0x00 | not used 0x00 | |||
Example
Value: 123456
CAN-ID:0x7FD
DLC: 8 Byte
Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 |
0x05 | 0x40 | 0xE2 | 0x01 | 0x00 | 0x00 | 0x00 | 0x00 |
Button Functionality
Button with Numbers (1, 2, 3, 4, 5, 6, 7, 8, 9, 0)
When pressing one of these buttons the number will be added on last position of the number field. If the Number is out of Range of signed word the value will be zero “0”.
Button “+-”
If the button “+-” is pressed the value will be negated (e.g. 123 → -123 or -234 → 234).
Button “ESC”
If the button “ESC” is pressed the field for the value will be cleared and show a zero “0”.
1.1.1 Button “OK”
The message will be sent after releasing the button. CAN-ID: 0x7FC
DLC: 8 Byte
Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 |
U16 Template number 0x0008: Template 5 | I32 Value -2147483648 … 2147483647 | 0x00 | 0x00 | ||||
Example
When the button “OK” gets pressed and Value 123456 was shown. CAN-ID: 0x7FC
DLC: 8 Byte
Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 | Byte 5 | Byte 6 | Byte 7 |
0x0008 | 0x0001E240 | 0x00 | 0x00 | ||||