C M L 1 2 S D P 2 5 6 | 0 7 / 1 7 / 0 2 |
JP1 and JP2
JP1 and 2 option jumpers provide an easy method of connecting or isolating the HCS12 SCI0 and SCI1 serial channel RXD pins respectfully from the provided on-board RS232 transceiver. To apply the RXD pins on the SCI channels for other user applications requires that the transceiver driver be removed from the HCS12 pin. User may then apply signals to the respective pins at the MCU PORT connector without driver conflict. Please note that the on- board monitor(s) require HCS12 SCI channel 0 (JP1 installed) for user interface.
CUT-AWAY OPTIONS 1 - 6
CUT-AWAY options allow the user to disconnect dedicated HCS12 I/O port resources from development board peripherals. The CUT-AWAY options also allow for establishing the connection again by installing surface mount 1206 size 0 ohm resistors or mod wire with the use of a soldering iron. Normal operation of the development board generally does not require any manipulation of the CUT_AWAY options.
#1 Cut-Away:HCS12 Port S5/MOSI signal to the LCD_PORT shift register.
#2 Cut-Away:HCS12 Port S7/SS0 signal to the LCD_PORT shift register.
#3 Cut-Away:HCS12 Port S6/SCK signal to the LCD_PORT shift register.
#4 Cut-Away:HCS12 Oscillator Crystal ground, if another crystal is applied by the user this connection may require a capacitor to be installed. Refer to the HCS12 CGM module information.
#5 Cut-Away:HCS12 Port M0/CAN_RXD0 signal to the CAN port transceiver.
#6 Cut-Away:CAN Port Transceiver enable connection to ground. This connection enables the CAN Port transceiver output to the CAN bus at all times. If the user wants to apply output enable or slew rate control to the transceiver, this option should be cut and 1206 size resistor applied for slew rate or a HCS12 I/O port applied for output enable control. See the PCA82C250 data sheet for application information.
PORTS AND CONNECTORS
TB1 and J1 Power
The TB1 and J1 connectors provide power input to the board or if J1 is used for input, TB1 maybe used to source additional circuitry. The J1 power jack accepts a standard 2.0 ~ 2.1mm center barrel plug connector (positive voltage center) to provide the +VIN supply of +7 to +20 VDC @ 80ma minimum (+9VDC nominal). TB1 provides access to the +VIN, GND (power ground), HCS12 core VDD, and +5V power supplies. The CML12Sxxx power supply will provide 50ma of +5V for user application. +VIN input power should only be applied by J1 or TB1, not both or a supply conflict may occur and the CML12Sxxx board could be damaged.