CML12C32SLK Freescale Semiconductor, CML12C32SLK Datasheet - Page 15

• Manufacturer Part Number: CML12C32SLK
• Description: KIT STUDENT LEARNING 16BIT HCS12
• Manufacturer: Freescale Semiconductor
• Type: MCUr

Specifications of CML12C32SLK

• Contents: *
• For Use With/related Products: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

C M L - 1 2 C 3 2
COMMUNICATIONS
The CML-12C32 board provides a single RS-232 communications port consisting of a 9-pin
DSUB connector and an RS-232 transceiver. The transceiver (U7) provides RS-232 signal
level to TTL/CMOS logic level translation. Serial communications signals TXD and RXD are
routed from the transceiver to MCU. The remaining signals are available at test points located
behind the COM connector. RTS has been biased properly to support 2-wire RS-232 commu-
nications.
Figure 1: COM1 Connector
CAN PORT
This port provides a CAN Bus interface associated with MCU CAN channel. The port has a
CAN Transceiver (Philips PCA82C250) capable of up to 1M Baud data rate. The user may
isolate the MCU CAN channel from the transceiver by cut-traces CT3, CT4, and CT5.
CAN BUS TRANSMIT ENABLE
The CAN port transceiver transmit driver is enabled for maximum drive and minimum slew rate
by default. The drive and slew rate may be adjusted by cutting cut-trace CT6 and adding a
1206 size surface mount resistor, see the PCA82C250 data sheet for details on resistor value
selection.
CAN Bus Transceiver transmit enable control can be applied to the port using the RS tie pad.
The user should select an available MCU I/O port to perform the transmit enable function and
connect it from the MCU_PORT pin to the RS pad as required. The transmit enable signal to
the CAN transceivers is active low logic.
CAN BUS TERMINATION
The CAN port provides RC11, RC12, and RC13, 1206 SMT size, termination resistor locations
on the bottom side of the CML-12C32 board. These termination resistors are not installed at
NOTE: Cut-trace, CT6, must be open to use the transmit enable control sig-
nal.
GND
RXD
TXD
1
2
3
4
5
1
2
3
4
GND
CAN-H
CAN-L
+5V
6
7
8
9
RTS
CTS
N/C
The CAN Port connector provides an interface to the
MSCAN12 channel in the MCU.
Female DB9 connector that interfaces to the MCU internal SCI
serial port via the RS232 transceiver (U7). It provides simple 2-
wire asynchronous serial communications without flow control.
Flow control is provided at test points on the board.
Pins 1, 4, and 6 are connected together.
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2 6 ,
2 0 0 4