Overview - Xilinx MIcroBlaze Development Spartan-3E 1600E Kit User Manual

R
RS-232 Serial Ports

Overview

As shown in
ports: a female DB9 DCE connector and a male DTE connector. The DCE-style port
connects directly to the serial port connector available on most personal computers and
workstations via a standard straight-through serial cable. Null modem, gender changers,
or crossover cables are not required.
Use the DTE-style connector to control other RS-232 peripherals, such as modems or
printers, or perform simple loopback testing with the DCE connector.
Figure 7-1
FPGA supplies serial output data using LVTTL or LVCMOS levels to the Maxim device,
which in turn, converts the logic value to the appropriate RS-232 voltage level. Likewise,
the Maxim device converts the RS-232 serial input data to LVTTL levels for the FPGA. A
series resistor between the Maxim output pin and the FPGA's RXD pin protects against
accidental logic conflicts.
Hardware flow control is not supported on the connector. The port's DCD, DTR, and DSR
signals connect together, as shown in
connect together.
MicroBlaze Development Kit Spartan-3E 1600 Edition User Guide
UG257 (v1.1) December 5, 2007
Figure 7-1, the MicroBlaze Development Kit board has two RS-232 serial
shows the connection between the FPGA and the two DB9 connectors. The
Figure 7-1. Similarly, the port's RTS and CTS signals
Chapter 7
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