Motorola 68HC12BC32 - Manual (Page 10)

10
CONFIG SWITCH
The CME-12B/BC board is shipped from the manufacturer with the following default CONFIG
SWITCH settings:
1 2 3 4 5 6 7 8
ON ON ON ON OFF ON OFF OFF
The 8 position CONFIG SWITCH provides an easy method of configuring the CME-12B/BC32
board operation. Following are the configuration switch descriptions and HC12 I/O port
usage:
CONFIG
SWITCH
OPERATION when in ON position HC12 I/O PORT USED
1
MODE A selection (see Mode chart
below)
MODA / PE5
2
MODE B selection (see Mode chart
below)
MODB / PE6
3 EXT –External Memory enable
(1)
N/A
4 MON –Monitor Memory enable
(2)
N/A
5 VPP - Flash VPP voltage enable N/A
6 RXD - Serial Port RXD input enable PS0 / RXD
7 PC0 –CAN Port RXCAN enable PC0
8 PC1 –CAN Port TX enable PC2
(1)
Enables memory bus operation for access to board memory. Expanded bus must be
on for proper operation.
(2)
Enables monitor EPROM’s in memory map at 0x8000 – FFFF hex if CONFIG
SWITCH position 3 is also on. When in off position memory space is SRAM for BDM
use.
MODE CHART
Single Chip Mode A and B = OFF
Expanded Wide Mode A and B = ON
MEM-SEL JUMPERS
Memory sockets U4/5 are shipped with 32K byte RAM devices. U6/7 are shipped with 32K
byte EPROM devices programmed with the D-bug12 monitor.
1,3,4 IN: enables RAM or EEPROM, 32K devices to U6/7
1,3 IN: enables RAM or EEPROM, 8K devices in U6/7
2,4 IN: enables EPROM, 8K or 32K devices in U6/7 (Default)