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Table of Contents
RASCII
Definition
The RASCII protocol uses HEXA for all fields except the prefix and remark text.
Command
| Prefix | Length | Command | Data | Example |
|---|---|---|---|---|
| @ | 00…FF | 00…FF | 0…n | @040101 |
Response
| Prefix | Length | Command | Data | Example |
|---|---|---|---|---|
| & | 00…FF | 00…FF | 0…n |
Event
| Prefix | Length | Event | Data | Example |
|---|---|---|---|---|
| $ | 00…FF | 00…FF | 0…n | $100200010102030405 |
Info
| Prefix | Length | Text | Example |
|---|---|---|---|
| # | 00…FF | 0…n | #0CRocDino V0.1 |
The info text may not contain any of the prefixes. This will make the message invalid and will be rejected.
HEXA
HEXA is the Hexadecimal-ASCII representation of a binary number.
A decimal value of 47, for example, is represented in HEXA as "2F".
Code examples
Convert a HEXA string to a Byte value
Paratemers:
- s = HEXA string
Returns: The byte value
byte HexA2Byte( const char* s ) { byte h, l, val; if( s[0] >= 'A' ) h = s[0] - 55; else h = s[0] -48; if( s[1] >= 'A' ) l = s[1] - 55; else l = s[1] -48; val = l + (h << 4); return val; }
Convert a Byte value to a HEXA string
Paratemers:
- b = Byte value
- s = Buffer for receiving the HEXA string
Returns: The pointer to the HEXA string buffer
const char* Byte2HexA(byte b, char* s) { static char cHex[] = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; s[0] = cHex[(b&0xF0)>>4]; s[1] = cHex[ b&0x0F ]; s[2] = '\0'; return s; }
Read sequence
- Read byte by byte until a prefix is detected.
- Read the next two HEXA characters and convert them to a number for the length.
- Read the number of bytes as set in the length field.
- Convert the HEXA to Bytes.
- Evaluate the message.
- Repeat.
Commands
Board # FF is broadcast.
| Code | Board | Description | Parameters | Reply |
|---|---|---|---|---|
| 0 | # | Get information | none | A remark with version information. |
| 1 | # | Start | none | A remark. |
| 2 | # | Stop | none | A remark. |
| 3 | # | Get config | none | The board configuration response. |
| 4 | # | Set config | The board configuration. | |
| 5 | # | Reset config | none | |
| 6 | # | Get CV | CV number | A CV number and value response. |
| 7 | # | Set CV | CV number, value | A remark. |
| 10 | # | Digital output | Address, port, on/off | - |
| 11 | # | Analog output | Address, Port, value | - |
| 12 | # | Accessory | Address, Port, aspect1) | - |
| 13 | # | Mobile speed | Address-High, Address-Low, direction/speed2) | - |
| 14 | # | Mobile function | Address-High, Address-Low, function, value | - |
| 15 | # | Mobile CV get | Address-High, Address-Low, CV-High, CV-Low | A CV number and value response. |
| 16 | # | Mobile CV set | Address-High, Address-Low, CV-High, CV-Low, value | - |
| 126 | # | Poll RS485 | none | Queued event, reply or an ACK if the queue is empty. |
| 127 | # | Acknowledge | Code | none |
Addressing Output/Accessory
Flat 16 bit addressing is used in case the port value is set to zero.
Events
Board # FF is broadcast.
| Code | Board | Description | Parameters | Remark |
|---|---|---|---|---|
| 1 | # | Occupancy | Port, Status on/off | |
| 2 | # | RFID | Port, RFID bytes | All RFID bytes may be set zero to signal depart. Sending a one byte zero ID will also be evaluated as departed. |
| 3 | # | Digital input | Port, on/off | |
| 4 | # | Analog input | Port, value H/L |
Events maybe acknowledged by the host program.
Libraries
Arduino
Trouble shooting
Windows crash nach Rocrail start
Some Windows configurations will crash at Rocrail server startup if the Arduino is connected by USB and the following option is not set: