FDC37M60X SMSC Corporation, FDC37M60X Datasheet - Page 18

• Manufacturer Part Number: FDC37M60X
• Description: ENHANCED SUPER I/O CONTROLLER WITH INFRARED SUPPORT
• Manufacturer: SMSC Corporation

TAPE DRIVE REGISTER (TDR)
Address 3F3 READ/WRITE
The Tape Drive Register (TDR) is included for
82077 software compatibility and allows the
user to assign tape support to a particular drive
during initialization.
that drive automatically invokes tape support.
The TDR Tape Select bits TDR [1:0] determine
the tape drive number. Table 4 illustrates the
Tape Select bit encoding. Note that drive “0” is
the boot device and cannot be assigned tape
support.
bits TDR.[7:2] are tristated when read. The TDR
is unaffected by a software reset.
Bit 7
Bit 7
X
X
X
X
X
X
1
0
1
0
DIGITAL OUTPUT REGISTER
DIGITAL OUTPUT REGISTER
Bit 6
Bit 6
X
X
X
X
X
X
1
0
1
0
The remaining Tape Drive Register
Bit 5
Bit 5
X
X
X
X
X
X
1
0
1
0
Table 6 - Internal 2 Drive Decode - Drives 0 and 1 Swapped
Any future references to
Bit 4
Bit 4
X
X
X
X
X
X
1
0
1
0
Table 5 - Internal 2 Drive Decode - Normal
Bit1
Bit1
X
X
0
0
1
1
0
0
1
1
Bit 0
Bit 0
0
1
0
1
X
0
1
0
1
X
OUTPUTS (ACTIVE LOW)
OUTPUTS (ACTIVE
nDS1
nDS1
DRIVE SELECT
18
DRIVE SELECT
0
1
1
1
1
1
0
1
1
1
LOW)
TAPE SEL1
(TDR.1)
0
0
1
1
nDS0
nDS0
1
0
1
1
1
Table 4- Tape Select Bits
0
1
1
1
1
TAPE SEL0
MOTOR ON OUTPUTS
(TDR.0)
MOTOR ON OUTPUTS
nMTR1
nBIT 4
nBIT 4
nBIT 4
nBIT 4
nBIT 4
nMTR1
nBIT 5
nBIT 5
nBIT 5
nBIT 5
nBIT 5
0
1
0
1
(ACTIVE LOW)
(ACTIVE LOW)
nMTR0
nBIT 5
nBIT 5
nBIT 5
nBIT 5
nBIT 5
SELECTED
nMTR0
nBIT 4
nBIT 4
nBIT 4
nBIT 4
nBIT 4
DRIVE
None
1
2
3