RS-232/422/485 Setup (Composite)

RS-232/422/485 Setup block


Simulink® Real-Time™ Library for RS-232


A setup block is a subsystem block that sets up the interface characteristics for the board.

For Quatech® boards, this setup block is for one channel or port.

The Commtech/Fastcom and Quatech boards and blocks will be removed in a future release. Do not use them in new models. Instead, use boards and blocks available from

Block Parameters

Port (Quatech, Commtech)

From the list, choose a port. The Port parameter defines the port this driver block configures.

Baud Divisor (Commtech)

Enter a divisor integer. The block determines the actual baud rate for a particular channel by dividing the maximum baud rate by this divisor. This number can be different for each channel.

Baud rate (Mainboard, Quatech)

From the list, choose a baud rate.

Number of data bits

From the list, choose either 5, 6, 7 or 8 to define the number of data bits for the port.

Number of stop bits

From the list, choose either 1 or 2 to define the number of stop bits for the port.


From the list, choose None, Even, Odd, Mark or Space. This parameter defines the receive and transfer parity.

Fifo mode (Mainboard, Quatech)

From the list, choose 64 deep, 16 deep, or 1 deep. This parameter sets the transmit and receive FIFO depth. The UART can operate with a FIFO depth of 1 character (1 deep), 16 characters (16 deep), or 64 characters (64 deep).

Receive trigger level

From the list, choose 1, quarter full, half full, or almost full. This parameter defines a trigger level for a receive data available interrupt. When the FIFO reaches the level specified in this parameter, the driver asserts the receive data available interrupt.

Enable auto RTS/CTS

Select this check box to enable handshaking using the RTS and CTS modem control lines. If this is not checked, handshaking is not done.

Base Address (Mainboard, ISA)

Enter the base address of the board that you are setting up.

Slot (PCI boards)

If only one board of this type is in the target computer, enter -1 to automatically locate the board.

If two or more boards of this type are in the target computer, enter the bus number and the PCI slot number of the board associated with this driver block. Use the format [BusNumber, SlotNumber]. To determine the bus number and the PCI slot number, type:

tg = slrt;
getPCIInfo(tg, 'installed')

Introduced before R2006a

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