C M L 1 2 S D P 2 5 6
0 1 / 3 0 / 0 4
20
1) The LCD write requires 3 SPI transfers. Transfer 1 provides data 0 - 3 and RS (register
select) value. Transfer 2 provides the same data with the EN (D7) bit set. Transfer 3
provides same data with the EN bit clear.
2) Resistor R25 can be removed to apply and external VEE potential.
3) CUT-AWAY 1 - 3 provide a means to isolate the LCD Port from the HCS12 SPI channel.
BDM PORT
The BDM port is a 6 pin header compatible with the Motorola Background Debug Mode (BDM)
Pod. This allows the connection of a background debugger for software development,
programming and debugging in real-time without using HC12 I/O resources.
BGND
1 2
GND
3 4
/RESET
5 6
+5V
See the HC12 Technical Reference Manual for complete
documentation of the BDM.
A Background Debug Module is available from the manufacturer.
TEST POINTS
The following test points are provided on the development board:
EXTAL :
HCS12 oscillator or external clock input pin.
XTAL :
HCS12 oscillator output pin.
XFC :
HCS12 PLL reference voltage and filter.
VDDPLL :
HCS12 PLL voltage source test point.
