Hardware Manual

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Programmable Hardware Manual - WS1102 © 2021 Tibbo Technology Inc
WS1102 Programmable Wireless RS232/422/485 Controller
RS232
RS422***
RS485***
#1
<No connection>
RTS– (output)
<No connection>
#2
RX (input)
RX– (input)
RX– (input)
#3
TX (output)
TX+ (output)
TX+ (output)
#4
DTR (output)*
TX– (output)
TX– (output)
#5
Ground
Ground
Ground
#6
DSR (input)**
RX+ (input)
RX+ (input)
#7
RTS (output)
RTS+ (output)
<No connection>
#8
CTS (input)
CTS+ (input)
<No connection>
#9
<No connection>
CTS– (input)
<No connection>
* When serial debugging is enabled, this line ceases to work as the DTR line of the serial port and
becomes the TX line of the debug serial port.
** When serial debugging is enabled, this line ceases to work as the DSR line of the serial port and
becomes the RX line of the debug serial port.
*** Serial debugging is not possible in these modes.
Selecting the serial port mode
On the WS1102, the serial port mode is controlled via Microchip's MCP23008 I/O expander IC.
The I²C interface of this IC is connected to GPIO5 and GPIO6 of the WS1102's CPU, as shown in
the diagram below.