Mitsubishi Electric Apricot LS Pro, Hardware Technical Reference

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Memory and I/O Usage
Chapter 4
Chapter 6
Appendix A
Appendix C
Pr
eface
Chapter 4Chapter 5
5/14 LS PRO HARDWARE TECHNICAL REFERENCE
Hard disk drive controller registers
The hard disk drive embedded controller is accessed at the locations given in the
following table.
Address R/W Function
01F0 R/W Data register
01F1 R Error register
01F1 W Write precompensation cylinder register
01F2 R/W Transfer sector count
01F3 R/W Starting sector count
01F4 R/W Low byte of cylinder number
01F5 R/W High byte of cylinder number
01F6 R/W Drive/head select register
01F7 R Status register
01F7 W Command register
03F6 R Fixed disk status register
03F6 W Fixed disk control register
03F7 W Fixed/floppy disk digital input register
These ports are defined in ANSI specification: ATA (AT attachment) X3T9.2/9-143.
Serial port controller registers
Each serial port controller has several accessible registers which are for control and
data transfer. The following table shows where each register is located in I/O space for
each port.
COM1 COM2 R/W Register
03F8 02F8 W Transmit data register (DLAB=0)
03F8 02F8 R Receive data register (DLAB=0)
03F8 02F8 R/W Divisor latch, low byte (DLAB=1)
03F9 02F9 R/W Divisor latch, high byte (DLAB=1)
03F9 02F9 R/W Interrupt enable register (DLAB=0)
03FA 02FA R Interrupt ID register
03FB 02FB R/W Line control register
03FC 02FC R/W Modem control register
03FD 02FD R Line status register
03FE 02FE R Modem status register
03FF 02FF R/W Scratch register
The registers are described in detail in the manufacturers data sheets.
Note
Rev C system boards are not fitted with the second serial port (COM2).