M 5 2 2 3 3 D E M O
S E P T E M B E R 2 5 , 2 0 0 6
14
LOW-POWER MODES
The MCF52233 supports several operational modes designed to reduce power consumption.
Low-power modes include Wait, Doze, Stop, and Halt. Refer to the MCF52235 documentation
at
www.freescale.com
for details on configuring and using the various low-power modes.
TIMING
Timing to the M52233DEMO clock module is provided by an external, 25 MHz crystal oscilla-
tor. Refer to the MCF52235 documentation at
www.freescale.com
for details on use and con-
figuration of the clock module.
COMMUNICATIONS
The M52233DEMO board provides 2 SCI ports, 1 QSPI port, and 1 IIC port. RS-232 commu-
nication is supported through a DB9 (COM) connector and through connector J1. QSPI and
IIC communications are supported only through connector J1. The COM_EN option header
enables SCI0 functionality between the MCU and the COM connector.
SCI Port
An RS-232 transceiver provides RS-232 to TTL/CMOS logic level translation between the
COM connector and the MCU. The COM connector is a 9-pin Dsub, right-angle connector. A
ferrite bead on shield ground provides conducted immunity protection. Communication signals
TXD0 and RXD0 are routed from the transceiver to the MCU. These signals are also available
on connector J1. Hardware flow control signals RTS0 and CTS0 are also routed from the
transceiver to the MCU. RTS is biased for correct 2-wire operation.
SCI1 signals are available on connector J1 and route directly between the MCU and connector
J1. No RS-232 logic-level translation is provided on SCI1 signals.
COM_EN
The COM_EN option header individually connects and disconnects SCI0 signals between the
MCU and the SCI transceiver. Removing a shunt disconnects the associated signal. Installing
a shunt connects the associated signal.
