ADwin-Pro
Hardware, manual version 2.9, June 2006
189
Pro I: Signal Conditioning and Interface Modules
Pro-RSxxx Rev. A
ADwin
Special features of RS485
Contrary to the RS232 interface more than 2 participants can communicate
with each other. With an RS485 interface a bus is set up.
Consider the following:
– There is no handshake, because a handshake is only possible between
two participants.
– The interface must know if it should write to the bus or get data from the
bus (
RS485_SEND
).
Module revisions
The difference between the revisions is described below:
Programming
All RSxxx-y modules are equipped with the Quad Universal Asynchronous
Receiver/Transmitter (UART), type TL16C754 from Texas Instruments
®
.
Functionality and programming of the interface depend on this controller. The
modules are easily programmed by
ADbasic
instructions, which can be found
in the include file
<ADPEXT.INC>
:
The instructions are described more detailed in the Pro software manual or the
online help.
Revision
Release
date
Previous changes
A1
First version
A2
09/2002
New printed circuit layout
A3
10/2003
Internal program optimization
Area
Instructions
Initialization
RS_INIT
,
RS_RESET
Receiving and transmitting of data
RS485_SEND
,
READ_FIFO
,
WRITE_FIFO
Write and read access to the controller
register
GET_RS
,
SET_RS
