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STATE #2 - "Check External Memory"
- "Enable External Memory"
- Set PCS7 to $30
(This turns on external chip selects: CS4 and CS5 from the W65C265S.)
- Check location $00:8000-$00:8002 for the string 'WDC', using CS4.
If the string is there, transfer control to USER program in EXTERNAL
MEMORY.
(JMP $00:8004)

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STATE #4 - "Miscellaneous Initialization"
- Set PCS7 to $FB
(This turns on external chip selects: CS0,1,3,4,5,6, and 7)
- Start the fast clock. (Don't use it, just start it.)
- Initialize the RAM interrupt vectors.
- Delay while fast clock becomes stable.
- Switch to fast clock.
- Set Timer 1 for a 1 second interrupt (ToD timer).
- Enable T1 interrupt (but not the I bit yet).
- Set up pointers to the serial buffers in internal RAM.
- Calculate the fast crystal frequency by comparing it to the 32 KHz clock
crystal.
- Finally, check the Time-of-Day clock checksum.
If the clock checksum is valid, proceed to STATE #6.
Else perform additional initialization in STATE #5.

STATE #5 - "Initialize Time-of-Day Clock"
- Reset the Time-of-Day clock and reset the baud rate counters for the
serial port to the default values.
- Set up control port of serial UARTs.
- Proceed to STATE #6.

STATE #6 - "Enable interrupts/Output start-up message"
- Read the serial UART #3 port to clear any initial trash data.
- Enable interrupts. (CLEAR THE I BIT)
- Output the initial message to the console.
- Transfer control to the command interpreter.