LPC47M192 View Datasheet(PDF) - SMSC -> Microchip
Part Name
Description
MFG CO.
'LPC47M192' PDF : 228 Pages View PDF
Table 4 – Internal 2 Drive Decode – Drives 0 and 1 Swapped
DIGITAL OUTPUT
REGISTER
DRIVE SELECT OUTPUTS
(ACTIVE LOW)
Bit 5 Bit 4 Bit1 Bit 0
X
1
0
0
1
X
0
1
0
0
X
X
nDS1
0
1
1
nDS0
1
0
1
MOTOR ON OUTPUTS
(ACTIVE LOW)
nMTR1
nMTR0
nBIT 4
nBIT 5
nBIT 4
nBIT 5
nBIT 4
nBIT 5
BIT 6 MOTOR ENABLE 2
The MTR2 disk interface output is not supported in the LPC47M192.
BIT 7 MOTOR ENABLE 3
The MTR3 disk interface output is not supported in the LPC47M192.
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. Any future references to that drive automatically invokes tape
support. The TDR Tape Select bits TDR.[1:0] determine the tape drive number. Table 5 illustrates the Tape Select Bit
encoding. Note that drive 0 is the boot device and cannot be assigned tape support. The remaining Tape Drive
Register bits TDR.[7:2] are tristated when read. The TDR is unaffected by a software reset.
Table 5 – Tape Select Bits
TAPE SEL1
(TDR.1)
0
0
1
1
TAPE SEL0
(TDR.0)
0
1
0
1
DRIVE
SELECTED
None
1
2
3
Normal Floppy Mode
Normal mode.Register 3F3 contains only bits 0 and 1. When this register is read, bits 2 – 7 are ‘0’.
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
REG 3F3
0
0
0
0
0
0
tape sel1 tape sel0
Enhanced Floppy Mode 2 (OS2)
Register 3F3 for Enhanced Floppy Mode 2 operation.
DB7
DB6
REG 3F3 Reserved Reserved
DB5
DB4
Drive Type ID
DB3
DB2
DB1
DB0
Floppy Boot Drive tape sel1 tape sel0
Table 6 – Drive Type ID
DIGITAL OUTPUT REGISTER
Bit 1
Bit 0
0
0
0
1
1
0
1
1
REGISTER 3F3 – DRIVE TYPE ID
Bit 5
Bit 4
L0-CRF2 – B1
L0-CRF2 – B0
L0-CRF2 – B3
L0-CRF2 – B2
L0-CRF2 – B5
L0-CRF2 – B4
L0-CRF2 – B7
L0-CRF2 – B6
Note: L0-CRF2-Bx = Logical Device 0, Configuration Register F2, Bit x.
SMSC DS – LPC47M192
Page 35
DATASHEET
Rev. 03/30/05
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