
IT8673F
5
55
Table 11-12. Status Register 2 (ST2)
Bit
Symbol
Name
Description
7
NU
Not Used
-
6
CM
Control Mark
This flag bit is set when either of the following conditions is met:
1. The FDC finds a Deleted Data Address Mark during a READ DATA
command, or
2. The FDC finds a Data Address Mark during a READ DELETED DATA
command
5
DD
Data Error in
Data Field
This flag bit is set when a CRC error is found in the data field.
4
WC
Wrong Cylinder This flag bit is set when the track address in the ID field is different from the track
address specified in the FDC.
3
SH
Scan Equal Hit
This flag bit is set when the condition of "equal" is satisfied during a SCAN
command.
2
SN
Scan Not
Satisfied
This flag bit is set when the FDC cannot find a sector on the cylinder during a
SCAN command.
1
BC
Bad Cylinder
This flag bit is set when the track address equals “FFh” and is different from
the track address in the FDC.
0
MD
Missing Data
Address Mark
This flag bit is set when a Data Address Mark or Deleted Data Address Mark
cannot be found by the FDC.
Table 11-13. Status Register 3 (ST3)
Bit
Symbol
Name
Description
7
FT
Fault
Indicates the current status of the Fault signal from the FDD.
6
WP
Write Protect
Indicates the current status of the Write Protect signal from the FDD.
5
RDY
Ready
Indicates the current status of the Ready signal from the FDD.
4
TK0
Track 0
Indicates the current status of the Track 0 signal from the FDD.
3
TS
Two Side
Indicates the current status of the Two Side signal from the FDD.
2
HD
Head Address
Indicates the current status of the Head Select signal to the FDD.
1-0
US1, US0 Unit Select
Indicate the current status of the Unit Select signals to the FDD.