Control and Status Registers

These two I/O-mapped registers provide miscellaneous system control and status.

	Port 0xE1 (R/W):
 		 Bit  7  - Bootloader mode
		 Bit  6  - LPT auto-strobe disable
 		 Bit  5  - (RO) DIP switch 2 on (MIRE 1.0 only, reads 0 on MIRE 1.1)
 		 Bit  4  - (RO) DIP switch 1 on (32KB SRAM disabled)
 		 Bit  3  - (RO) Valid RS-232 levels detected (device attached)
 		 Bit  2  - RS-232 generate DCD from DSR (support for incorrectly-wired null modems)
 		 Bit  1  - Reserved
 		 Bit  0  - Unused output pin control

	Port 0xE2 (R/W):
 		 Bit  7  - (RO) Unused input pin status
		 Bit  6  - (RO) Unused input pin status
 		 Bit  5  - (RO) Unused input pin status
 		 Bit 4:3 - Reserved 
 		 Bit  2  - Disable PIC processor registers
 		 Bit  1  - Disable version number registers
 		 Bit  0  - Disable RS-232 module

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