Option Switches, Config Switch, COM Switch

OPTION SWITCHES

CONFIG SWITCH

The CMD912X board is shipped from the manufacturer	1	2	3	4	5
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	OPERATION when in ON position
	SWITCH	OPERATION when in ON position
	SWITCH
	1	EXT – External Memory and PRU enable (1)
	2	MON – Monitor Memory enable (2)
	3	MON SEL - Select NOICE Debug kernel
	4	ECS Enable - Enable ECS (Emulation Chip Select) signal to ram for
	4	paging emulation on Devices larger than 60K
		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

HC12 Connection in the ON position

SWITCH

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.