Protocol
ArduRPC brings remote procedure calls to microcontrollers. The binary protocol has been designed to be simple and flexible. Basic and also complex data types are supported.
Communication
Request
| Name |
Type |
Comment |
|---|
| Version |
uint8 |
Protocol version (default: 0) |
| Handler ID |
uint8 |
ID of the handler |
| Command ID |
uint8 |
ID of the command to call |
| Length |
uint8 |
Length of data in bytes |
| Data |
|
List of parameters |
- Version:
- This is the version of the protocol. At the moment only version 0 is supported.
- Handler ID:
- The ID of the handler to use.
- Command ID:
- The ID of the command to call.
- Length:
- Length of the data in bytes.
- Data:
- A list of parameters. See Data Types for more information.
Response
| Name |
Type |
Comment |
|---|
| Return code |
uint8 |
The return code. See Return codes |
| Data |
Mixed |
The result |
- Data:
- The result data. Only one type of data is allowed.
Data Types
Basic data types
Basic data types have a fixed length like a signet Integer.
Data Types
| Identifier |
Data Type |
Size in Bytes |
|---|
| 0x00 |
None |
0 |
| 0x01 |
Signed Char |
1 |
| 0x02 |
Unsigned Char |
1 |
| 0x03 |
Signet Short |
2 |
| 0x04 |
Unsigned Short |
2 |
| 0x05 |
Signed Long |
4 |
| 0x06 |
Unsigned Long |
4 |
| 0x07 |
Signed Long Long |
8 |
| 0x08 |
Unsigned Long Long |
8 |
| 0x09 |
Float |
4 |
Data structure:
| Name |
Type |
Comment |
|---|
| Identifier |
uint8 |
The identifier. See Data types for more information. |
| Data |
|
The data specified by the identifier. |
Complex data types
At the moment the following data types are supported.
| Identifier |
Data Type |
|---|
| 0x10 |
Simple array |
| 0x11 |
String |
| 0x12 |
Multicolumn array |
| 0x13 |
Value array |
Array:
| Name |
Type |
Comment |
|---|
| Identifier |
uint8 |
Set to 0x10. See data types for more information. |
| Data Identifier |
uint8 |
Basic data type of the elements. |
| Length |
uint8 |
Length of the string in bytes. |
| Data |
|
The string. |
String:
| Name |
Type |
Comment |
|---|
| Identifier |
uint8 |
Set to 0x11. See data types for more information. |
| Length |
uint8 |
Length of the string in bytes. |
| Data |
|
The string. |
Multi column array:
| Name |
Type |
Comment |
|---|
| Identifier |
uint8 |
Set to 0x12. See data types for more information. |
| Columns |
uint8 |
Number of columns. |
| Column Identifier 1 |
uint8 |
The identifier for column 1 |
| Column Identifier m |
uint8 |
The identifier for column m |
| Length |
uint8 |
Number of rows |
| Row 1 |
|
Data of row 1 |
| Row n |
|
Data of row n |
Value array:
| Name |
Type |
Comment |
|---|
| Identifier |
uint8 |
Set to 0x13. See data types for more information. |
| Length |
uint8 |
Length of the array in bytes. |
| Data |
|
List of identifiers and values |
Return codes
| Code |
Comment |
|---|
| 0 |
Success |
| 124 |
Function not found |
| 125 |
Handler not found |
| 126 |
Command not found |
| 127 |
Failure no reason given |
Example
Basic data types
Request:
| Data |
Comment |
|---|
| 0x00 |
Protocol version (default: 0) |
| 0x03 |
ID of the handler. |
| 0x02 |
ID of the command to call |
| 0x05 |
Length of data in bytes |
| 0x10 |
Value: 16 (Type: uint8) |
| 0x00 |
Value: 1 (Type: uint16) |
| 0x01 |
Response:
| Data |
Comment |
|---|
| 0x00 |
Success |
| 0x01 |
Identifier for Unsigned Char |
| 0x10 |
Value: 16 |
Footnotes