Compaq dc7100 HP Compaq dc71xx and dx61xx Series Business Desktop Computers Te - Page 95

Diskette Drive Interface Control, Table 5-8.

Get Compaq dc7100 - Convertible Minitower PC PDF manuals and user guides View all Compaq dc7100 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 95 highlights

Input/Output Interfaces Diskette Drive Interface Control The BIOS function INT 13 provides basic control of the diskette drive interface. The diskette drive interface can be controlled by software through the LPC47B397's I/O-mapped registers listed in Table 5-8. The diskette drive controller of the LPC47B397 operates in the PC/AT mode in these systems. Table 5-8. Diskette Drive Interface Control Registers Primary Second. Address Address Register 3F0h 370h Status Register A: Interrupt pending Reserved (always 1) STEP pin status (active high) TRK 0 status (active high) HDSEL status (0 = side 0, 1 = side 1) INDEX status (active high) WR PRTK status (0 = disk is write protected) Direction (0 = outward, 1 = inward) 3F1h 371h Status Register B: Reserved (always 1's) DOR bit 0 status Write data toggle Read data toggle WGATE status (active high) MTR 2, 1 ON- status (active high) 3F2h 372h Digital Output Register (DOR): Reserved Motor 1, 0 enable (active high) DMA enable (active high) Reset (active low) Drive select (00 = Drive 1, 01 = Drive 2, 10 = Reserved, 11 = Tape drive) 3F3h 373h Tape Drive Register (available for compatibility) R/W R R R/W R/W Technical Reference Guide 361834-002 5-9

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
Technical Reference Guide
361834-002
5-9
Input/Output Interfaces
Diskette Drive Interface Control
The BIOS function INT 13 provides basic control of the diskette drive interface. The diskette
drive interface can be controlled by software through the LPC47B397's I/O-mapped registers
listed in Table 5-8. The diskette drive controller of the LPC47B397 operates in the PC/AT mode
in these systems.
Table 5-8.
Diskette Drive Interface Control Registers
Primary
Address
Second.
Address
Register
R/W
3F0h
370h
Status Register A:
<7> Interrupt pending
<6> Reserved (always 1)
<5> STEP pin status (active high)
<4> TRK 0 status (active high)
<3> HDSEL status (0 = side 0, 1 = side 1)
<2> INDEX status (active high)
<1> WR PRTK status (0 = disk is write protected)
<0> Direction (0 = outward, 1 = inward)
R
3F1h
371h
Status Register B:
<7,6> Reserved (always 1’s)
<5> DOR bit 0 status
<4> Write data toggle
<3> Read data toggle
<2> WGATE status (active high)
<1,0> MTR 2, 1 ON- status (active high)
R
3F2h
372h
Digital Output Register (DOR):
<7,6> Reserved
<5,4> Motor 1, 0 enable (active high)
<3> DMA enable (active high)
<2> Reset (active low)
<1,0> Drive select (00 = Drive 1, 01 = Drive 2, 10 = Reserved, 11 =
Tape drive)
R/W
3F3h
373h
Tape Drive Register (available for compatibility)
R/W