NCT6627UD Nuvoton Technology Corporation of America, NCT6627UD Datasheet - Page 116

• Manufacturer Part Number: NCT6627UD
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of NCT6627UD

• Lead Free Status / Rohs Status: Supplier Unconfirmed

The Main Status Register is used to control the flow of data between the microprocessor and the controller. The
bit definitions for this register are as follows:
DEFAULT
DEFAULT
9.2.5 Main Status Register (MS Register) (Read base address + 4)
BIT
BIT
NAME
7
6
5
4
3
2
1
0
7
6
BIT
BIT
TAPE SEL 1
Media ID1. Read only. Reflects the value of LD0, CRF1, bit 5.
Media ID0. Read only. Reflects the value of LD0, CRF1, bit 4.
Drive Type ID1.
Drive Type ID0.
Floppy Boot Drive 1. Reflects the value of LD0, CRF1, bit 7.
Floppy Boot Drive 0. Reflects the value of LD0, CRF1, bit 6.
Tape Sel 1.
Tape Sel 0.
Request for Master (RQM). A high on this bit indicates Data Register is ready to send or
receive data to or from the processor.
DATA INPUT/OUTPUT (DIO). If DIO = HIGH, then the transfer is from Data Register to
the processor. If DIO = LOW, the transfer is from processor to Data Register.
0
0
1
1
RQM
7
0
7
0
DIO
NA
6
0
6
Non-DMA
TAPE SEL 0
mode
NA
5
1
5
0
1
0
1
FDC Busy
DESCRIPTION
DESCRIPTION
NA
4
1
4
Reflect the bit in LD0, CRF2. Which bit is
reflected depends on the last drive selected
in the PO register.
Assign a logical drive number to the tape
drive. Drive 0 is not available as a tape
drive and is reserved for the floppy disk
boot drive.
FDD 3
Busy
-107-
NA
3
0
3
W83627UHG/NCT6627UD
DRIVE SELECTED
FDD 2
Busy
NA
Publication Release Date: October 26, 2010
2
0
2
None
1
2
3
FDD 1
Busy
NA
1
0
1
FDD 0
Busy
NA
0
0
0
Revision 1.7