Allen Bradley DF1 Connector
Overview
The Allen Bradley DF1 connector provides tag-based read/write access to legacy Allen Bradley PLCs (e.g. PLC-5, SLC 500, MicroLogix) over the serial DF1 protocol, using the AllenBradleyDF1Comms library. Unlike the Ethernet-based Allen Bradley/Omron connector, this communicates over a physical serial (RS-232/RS-485) connection.
Supports both auto-detected and manually configured baud rate/parity/checksum settings.
Parameters
| Name | Values | Description |
|---|---|---|
| Type | AB-DF1 | The connector type identifier. |
| Port | COM port name, e.g. COM3 | The serial port the PLC is connected to. |
| AutoDetect | true / false | If true, automatically detects baud rate/parity/checksum settings rather than using the values below. |
| BaudRate | integer | Serial baud rate. Required if AutoDetect is false. |
| Parity | EVEN / other (defaults to None) | Serial parity setting. Required if AutoDetect is false. |
| Checksum | BCC / other (defaults to CRC) | DF1 checksum type. Required if AutoDetect is false. |
| Retries | integer | Maximum send retries. Defaults to 5. |
| RetryDelay | milliseconds (integer) | Delay between send retries. Defaults to 100. |
| UpdateRate | milliseconds (integer) | How often tags are polled. Defaults to 1000. |
Supported Tag Types
| Tag Type | Address | Behaviour |
|---|---|---|
| Any standard tag | DF1-format address (e.g. N7:0, B3:0/1) | Read on every cycle if IOType is In/InOut. Written on value change if IOType is Out/InOut, via df1.WriteData. |
Connector Methods
| Name | Arguments | Description |
|---|---|---|
| (none) | - | This connector does not currently expose any custom connector-level methods via Execute Commands. |
Addressing
The Address field is a native DF1 address string as accepted by AllenBradleyDF1Comms.ReadAny/WriteData (e.g. integer file N7:0, bit B3:0/1).
Diagnostic Codes
| Code | Type | Description |
|---|---|---|
| 1040 | Error | Error writing |
| 1200 | Error | AB DF1 Connection Error (auto-detect failed) |
| 1206 | Error | DF1 Connection Failed |
| 1210 | Error | AB DF1 not connected - retry in 10s |
| 1215 | Error | AB DF1 failed to initialize/connect |
| 1305 | Error | Error reading (bad reading result, or exception during read) |
| 2300 | Debug | ITag not present |
| 3100 | Info | Started |
| 3205 | Info | DF1 Connection Success |