turck BL67 - Bl67-1 Rs232; Data Transfer Method; Data Exchange; Process Data

D300529 0115 - BL67 I/O modules
12-3
BL67-1RS232
12.1 BL67-1RS232
The module BL67-1RS232 transmits serial data through the BL67 system via a RS232 interface and
enables the connection of different devices (printer/scanner/bar code reader), which as well provide a
serial RS232 interface.
12.1.1 Data transfer method
The module enables flexible serial data transfer. An operational data transfer method can be set by the
module’s parameters.
The data transfer can be parameterized as follows:
 Data
rate: 300 bps to 115200 bps
 Data bits: 7 or 8 data bits in one data frame
 Parity: none, odd or even
 Stop bits: 1 or 2 bit.
NOTE
12.1.2 Data exchange
For the data exchange with a field device, the RS232-module provides a 64-byte transmit-buffer and a
128-byte receive-buffer. This is a hardware-restriction. The data telegrams which have to be sent or
received can be larger.
The data transfer from the PLC into
the transmit
-buffer of the RS232-module or from the receive-buffer
of the module to the PLC is realized via a 8-byte transmission channel in the process output or process
input data.
To ensure the error-free data transmissio
n
, 2 byte of each data package are used to display status-, con-
trol- and diagnosis information. The amount of user data is th
erefore reduced to 6 byte within a data
package
12.1.3 Process data
With PROFIBUS, PROFINET and CANopen, the I/O data of this modu
le is localized within the process
data of the whole station via the hardware configuration tool of the fieldbus master.
With DeviceNet, EtherNet/IP and Modbus TCP a detailed mapping table can be created with the
TURCK configuration tool I/O-ASSISTANT (PACTware + BL67-DTM).
Process input data
The RS232-module sends the data, received
by the device, into a 128-byte receive-buffer. The module
then transmits the data segmented via the module bus and the gateway to the PLC.
The transmission is realized in a 8-byte fo
rmat which is structured as follows:
 1 status byte
is required to ensure trouble-free transmission of the da
ta.
 1 byte contains the diagnostics data.
 6 bytes are used to contain the user data.
The data flow control can be realized via a hardware handshake (RTS/CTS) or a software hand-
shake (XON/XOFF).