Digilent 410-068P Rev.B User Manual
Digilent Hardware
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w w w . d ig i l en t inc . c om
Revision: June 6, 2012
Note: This document applies to REV B of the board.
215 E Main Suite D | Pullman, WA 99163
(509) 334 6306 Voice and Fax
Doc: 502-068
page 1 of 2
Copyright Digilent, Inc. All rights reserved. Other product and company names mentioned may be trademarks of their respective owners.
Maxim™
MAX3232
RS232
Transceiver
Pins 1,4,6 are tied
for handshaking.
NC
1
6
4
9
8
3
7
2
5
J1
1
2
3
4
5
6
CTS
RTS
TXD
RXD
JP1
JP2
RS232 Module Block Diagram
Overview
The PmodRS232 Converter Module Board (the
RS232 module) translates voltage from the
logic levels used by Digilent system boards to
the RS232 voltage used for serial
communications.
The RS232 module creates a two-way I/O
exchange by converting RS232 voltage to logic
level voltage and converting logic voltage to
RS232 voltage. RS-232 voltage levels are -3 to
-12V for a logic ‘1’, and +3 to +12 for a logic ‘0’.
The RS232 module is configured as a data
communications equipment (DCE) device. It
connects to data terminal equipment (DTE)
devices, such as the serial port on a PC, using
a straight-through cable.
Features include:
•
A Maxim Integrated™ MAX3232CSE
RS232 transceiver
•
a DB9 connector and 6-pin header
•
transmit and receive data functions
•
optional RTS and CTS handshaking
functions
•
small form factor (1.00” x 1.30”).
Functional Description
The RS232 module provides two transmit
buffers and two receive buffers. A transmit
buffer converts a logic-level signal on its input
to an RS232 voltage-level signal on its output.
A receive buffer converts an RS232 voltage-
level signal on its input to a logic-level signal
on its output.
The RS232 module can be configured as
either a 3-wire DTE serial port (with one
transmitter for transmit-data signals, one
receiver for receive-data signals, and a signal-
ground connection), or as a 5-wire DTE serial
port with an additional transmitter and receiver
for RTS and CTS handshaking signals,
respectively.
The RS232 module is designed to work with
either Digilent programmable logic system
boards or embedded control boards. Most
Digilent system boards (like the Basys, Nexys
or Cerebot) have 6-pin connectors that allow
the RS232 module to plug directly into the