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OPTION SWITCHES

CONFIG SWITCH

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The CMD912X board is shipped from the manufacturer
with the following default CONFIG SWITCH settings: ON ON OFF OFF OFF
The 5 position CONFIG SWITCH provides an easy method of configuring the CMD912X
board memory operation. Following are the configuration switch descriptions:
CONFIG
SWITCH OPERATION when in ON position
1EXT – External Memory and PRU enable (1)
2MON – Monitor Memory enable (2)
3MON SEL - Select NOICE Debug kernel
4ECS Enable - Enable ECS (Emulation Chip Select) signal to ram for
paging emulation on Devices larger than 60K
5FPAGE Enable - Enable DG/DT128 Fixed Page at $4000 hex
(1) Enables memory bus operation for access to board memory and PRU. Expanded Wide
bus mode must be enabled for proper operation.
(2) Enables monitor EPROM’s in memory map at 0xC000 – FFFF hex if CONFIG SWITCH
position 1 is also on. When in off position memory space is SRAM for BDM use.

COM SWITCH

The 6 position COM SWITCH on the CMD912x Board provides an easy method of connecting
or isolating the HC12 SCI and CAN channel RXD pins from the provided on-board
transceivers. The HC12 SCI channels are connected to RS232 transceivers and the first 4
CAN channels are connected to 1M baud CAN transceivers. To apply the RXD pins on the
channels for other user applications requires that the transceiver driver be removed from the
HC12 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 HC12 SCI channel 0
for user interface.
COM
SWITCH HC12 Connection in the ON position
1SCI0 RXD to COM1 RS232 Transceiver (1)
2SCI1 RXD to COM2 RS232 Transceiver
3CAN0 RXD to CAN1 Port Transceiver
4CAN1 RXD to CAN2 Port Transceiver
5CAN2 RXD to CAN3 Port Transceiver
6CAN3 RXD to CAN4 Port Transceiver
(1) Must be ON if using on board Monitor firmware.