14
MODE SWITCH
The 3 to 5 position MODE SWITCH on the PM12xxx Module provides an easy method of
configuring the HC12 operating Mode and Options from RESET.
NOTE: Expanded Narrow Mode is not available on this board, Expanded Wide
operation is required due to the memory application and that any expanded bus
operation requires both HC12 I/O ports A and B in any case.
Following are the Mode Switch selections and descriptions:

PM12D60

Default: 1 and 2 ON, 3 - 5 OFF.
MODE
SWITCH SELECTION
OPTION OFF POSITION ON POSITION
1 and 2 Operating Mode Single Chip Mode Expanded Wide Mode
3Port H pull device Port H Pull-Down Port H Pull-Up
4Port G pull device Port G Pull-Down Port G Pull-Up
5Oscillator Select Ext. 16Mhz Clock User applied crystal

PM12DG128 / PM12DT128

Default: 1 and 2 ON, 3 OFF
MODE
SWITCH SELECTION
OPTION OFF POSITION ON POSITION
1 and 2 Operating Mode Single Chip Mode Expanded Wide Mode
3Oscillator Select Ext. 16Mhz Clock User applied crystal

PM12DP256

Default: 1 - 3 ON, 4 and 5 OFF
MODE
SWITCH SELECTION
OPTION OFF POSITION ON POSITION
1 and 2 Operating Mode Single Chip Mode Expanded Wide Mode
3MODC Selection Normal Modes Special / Emulation Mode
4ROMON Select Internal Flash ON Internal Flash OFF
5Oscillator Select Ext. 16Mhz Clock User applied crystal