IBM DTLA-305040 Hard Drive Specifications - Page 83

Data Register, Device Control Register, Drive Address Register, Bit Definitions, SRST RST

Page 83 highlights

9.5 Data Register This register is used to transfer data blocks between the device data buffer and the host. It is also the register through which sector information is transferred on a Format Track command and configuration information is transferred on an Identify Device command. All data transfers are 16 bits wide, except for ECC byte transfers, which are 8 bits wide. Data transfers are PIO only. The register contains valid data only when DRQ=1 in the Status Register. 9.6 Device Control Register Device Control Register 7 6 5 4 3 2 1 0 - - - - 1 SRST -IEN 0 Figure 68. Device Control Register Bit Definitions SRST (RST) Software Reset. The device is held reset when RST=1. Setting RST=0 re-enables the device. The host must set RST=1 and wait for at least 5us before setting RST=0 to ensure that the device recognizes the reset. -IEN Interrupt Enable. When -IEN=0 and the device is selected, device interrupts to the host will be enabled. When -IEN=1 or the device is not selected, device interrupts to the host will be disabled. 9.7 Drive Address Register Drive Address Register 7 6 5 4 3 2 1 0 HIZ -WTG -H3 -H2 -H1 -H0 -DS1 -DS0 Figure 69. Drive Address Register This register contains the inverted drive select and head select addresses of the currently selected drive. Bit Definitions HIZ High Impedance. This bit is not driven and will always be in a high impedance state. -WTG -Write Gate. This bit is 0 when writing to the disk device is in progress. Deskstar 40GV & 75GXP hard disk drive specifications 71

  • 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

9.5
Data Register
This register is used to transfer data blocks between the device data buffer and the host. It is also the
register through which sector information is transferred on a Format Track command and configuration
information is transferred on an Identify Device command.
All data transfers are 16 bits wide, except for ECC byte transfers, which are 8 bits wide. Data transfers
are PIO only.
The register contains valid data only when DRQ=1 in the Status Register.
9.6
Device Control Register
0
–IEN
SRST
1
0
1
2
3
4
5
6
7
Device Control Register
Figure 68. Device Control Register
Bit Definitions
SRST (RST)
Software Reset. The device is held reset when RST=1. Setting RST=0 re-enables the
device.
The host must set RST=1 and wait for at least 5us before setting RST=0 to ensure that
the device recognizes the reset.
-IEN
Interrupt Enable.
When -IEN=0 and the device is selected, device interrupts to the host
will be enabled. When -IEN=1 or the device is not selected, device interrupts to the host
will be disabled.
9.7
Drive Address Register
–DS0
–DS1
–H0
–H1
–H2
–H3
–WTG
HIZ
0
1
2
3
4
5
6
7
Drive Address Register
Figure 69. Drive Address Register
This register contains the inverted drive select and head select addresses of the currently selected drive.
Bit Definitions
HIZ
High Impedance. This bit is not driven and will always be in a high impedance state.
-WTG
-Write Gate. This bit is 0 when writing to the disk device is in progress.
Deskstar 40GV & 75GXP hard disk drive specifications
71