IDE 硬件插针分布
-------硬件连接针功能描述
寄存器寻址方式
I/O端口简述
--------寄存器功能描述
命令描述
然后在os中引入硬盘驱动程序.
+-----+-------------+--------+--------+
| Pin | Drive Cable | Signal | AT Bus |
| No | Signal Name | Flow | Pin |
+-----+-------------+--------+--------+
| 1 | -Reset | <- | B2 |
| 2 | Ground | | B1 |
| 3 | D7 | <-> | A2 |
| 4 | D8 | <-> | C11 |
| 5 | D6 | <-> | A3 |
| 6 | D9 | <-> | C12 |
| 7 | D5 | <-> | A4 |
| 8 | D10 | <-> | C13 |
| 9 | D4 | <-> | A5 |
| 10 | D11 | <-> | C14 |
| 11 | D3 | <-> | A6 |
| 12 | D12 | <-> | C15 |
| 13 | D2 | <-> | A7 |
| 14 | D13 | <-> | C16 |
| 15 | D1 | <-> | A8 |
| 16 | D14 | <-> | C17 |
| 17 | D0 | <-> | A9 |
| 18 | D15 | <-> | C18 |
| 19 | Ground | | B1 |
| 20 | KEY | | |
| 21 | Reserved | | |
| 22 | Ground | | B1 |
| 23 | -IOW | <- | B13 |
| 24 | Ground | | B1 |
| 25 | -IOR | <- | B14 |
| 26 | Ground | | B1 |
| 27 | -IOCHRDY | -> | A10 |
| 28 | SPSYNC/ALE | <- | B28 |
| 29 | Reserved | | |
| 30 | Ground | | B1 |
| 31 | INTRQ | -> | D7 |
| 32 | -IOCS16 | -> | D2 |
| 33 | ADDR1 | <- | A30 |
| 34 | -PDIAG | | |
| 35 | ADDR0 | <- | A31 |
| 36 | ADDR2 | <- | A29 |
| 37 | -CS1FX | | |
| 38 | -CS3FX | | |
| 39 | -DASP | | |
| 40 | Ground | | B1 |
+-----+-------------+--------+--------+
-RESET
上电时, 电平稳定以后此pin至少有效 25 microseconds, 此后,要复位驱动器时才置有效.
D0...D15
双向数据总线. D0...D7 用于传输8 位数据,如寄存器和ECC数据.
KEY
防呆针.
-IOW
写选通. 在 -IOW 时钟的上升沿数据从host向驱动器传输.
-IOR
读选通. 下降沿有效.
-IOCHRDY
当此信号negated 时, 就会延长(阻塞) host 的寄存器访问的 cycle, 表示驱动器忙.当非negated 状态时处于高阻抗状态.
SPSYNC
spindle synchronization. This may be either input or output to the drive depending on a vendor defined switch. If a drive is set to MASTER the signal is output and if a drive is SLAVE the signal is input. There is no requirement that each drive implementation be plug compatible to the extent that a multiple vendor drive subsystem be operable. However if drives are designed to match the following recommendations then controllers can operate drives with a single implementation:
There can only be one MASTER drive at a time in a configuration. The host or the drive designated as master can generate SPSYNC at least once per revolution (it may be more than onceper revolution).
SPSYNC received by a drive is used as the synchronization signal to lock the spindles in step. The time to achieve synchronization varies and is indicated by the drive setting DRDY. If the drive does not achieve synchronization, it will not set DRDY.
A master drive or a host generates SPSYNC and transmits it. A slave does not generate SPSYNC and must be responsible to synchronize its index to SPSYNC. If a drive does not support synchronization, it will ignore SPSYNC. In the event that a previously synchronized drive loses synchronization, it does not clear DRDY.
Prior to the introduction of this standard, this signal was defined as ALE (Address Latch Enable) and was used for an address valid indication from the host system. If used, the host address and chip selects, ADDR0 through ADDR2, CS1FX- and CS3FX- were valid at the negation of this signal and remained valid while ALE was negated, therefore the drive did not need to latch these signals with ALE.
INTRQ
用于向cpu通知中断请求. 通过清除 设备控制寄存器的 nIEN 位使能中断请求. 下列情况下驱动产生中断请求:
驱动软件复位(assertion of -RESET).
设置 设备控制寄存器的SRST位.
向命令寄存器写命令.
读取状态寄存器.
NOTE: 一些驱动器在PIO数据传输结束的时候产生INTRQ, 只是在单个扇区读取或者多个扇区多操作的最后一个扇区不报中断. PIO 数据传输时,在每一数据块传输开始时报INTRQ. 大多数情况下数据块指的是单个扇区,除非设置了Multiple Command. 一个例外是:在 格式化磁道, Write Sector(s), Write Buffer and Write Long commands 的时候传输的一个数据块的开始不会 assert INTRQ.
-IOCS16
告知host 16 位数据端口有效,寻址完成,已经准备好收发16 bit数据. This signal is an open collector output. D8...D15 仅在-IOCS16 有效并且驱动器正在传输数据的时候有效. ECC 数据传输时, 仅仅使用 D0...D7.
ADDR0-2
选择驱动器内的一个寄存器或者数据端口.
-PDIAG
用于Drive 1 通知 Drive 0 自己已经通过自检. 在上电或者软件复位后, Drive 1 会在1 mesc 内取消 -PDIAG 指示Drive 0 忙. 然后,在30内 Drive 1 将使能-PDIAG , 意思是已经准备完成,可以提供状态数据. -PDIAG 有效后, Drive 1 也许还不能接受命令,要到driver 1 完成复位并置位 DRDY.
接受到Diagnostics command后, Drive 1 在1 msec内取消 -PDIAG 信号,通知Drive 0 自己处于busy 状态.如果 Drive 1 存在, Drive 0 将会等待driver 1 取消此信号最多5 msec. Drive 1 在有效-PDIAG 之前应该清除BUSY 状态, 因为-PDIAG 用于指示 Drive 1 通过自检准备 is re透底状态信息.
如果-DASP 没有在复位初始化时被Drive 1 置有效, Drive 0 将在完成自己的自检后马上投递自己的状态并将Drive 1 的状态寄存器清零. Drive 0 在完成复位并置DRDY之前将无法接受命令.
-CS1FX
由地址解码逻辑从主机地址线a3...a9产生的片选信号. 通常在I/O 操作时有效,操作ports 1F0 through 1F7. -CS1FX 用于访问八个硬盘命令寄存器块.
-CS3FX
由地址解码逻辑从主机地址线a3...a9产生的片选信号. 通常在I/O 操作时有效,操作ports 3F0 through 3F7. -CS3FX 在访问控制寄存器块,状态寄存器块,设备控制寄存器时有效,是8bit操作.
NOTE: primary 适配器通过 I/O addresses 1FX and 3FX 访问, secondary 适配器通过I/O addresses 17X and 37X访问.
-DASP
是一个分时复用的寄存器,指示drive active 或者Drive 1 存在.open collector output.上电初始化或者复位以后,Driver 1 在400Msec内使 -DASP 有效,通告他的存在. Drive 0 容许最多 450 msec 给 Drive 1 有效-DASP. 如果 Drive 1 不存在, Drive 0 可能使用 -DASP 驱动一个LED.
在Driver 1接受到第一个有效的命令后或者31秒后取消-DASP. 一旦取消 -DASP, 则任何一个驱动器都可以把它用作 activity indicator(比如LED?).
主机采用 I/O 方式寻址硬盘驱动器. 主机地址线 A0, A1, A2, 片选 CS1FX- and CS3FX-, IOR- 和 IOW- 寻址磁盘寄存器. 主机地址线 A3...A9 产生两个片选: CS1FX- and CS3FX-.片选CS1FX- 访问八个硬盘 命令寄存器组. 片选信号 CS3FX- 在和控制寄存器组交换8位的状态,控制,驱动器地址时有效.
A7 选择驱动器的master或alternate command block addresses.
(Note: 这意味着, host 提供了一个 primary 硬盘适配器, I/O 地址是1FX/3FX , 还提供一个secondary 适配器, I/O 地址17X/37X. 每一个适配器最多连接两块硬盘 [MASTER/SLAVED]).
下图是解码方式的图示:
HEX BINARY 描述
1FX 0001 1111 XXXX Primary Command Registers
3FX 0011 1111 XXXX Primary Control Registers
17X 0001 0111 XXXX Alternate Command Registers
37X 0011 0111 XXXX Alternate Control Registers
^
|
+--- Address bit A7
X 的意思是不关心
数据线 D8...D15 仅在 IOCS16- 有效期间并且驱动器正在传输数据时有效. ECC 信息仅仅出现在数据线D0...D7 ,此种传输中D8...D15 是无效的.
+----+------+------+---+---+---+----------------+---------------+
|Addr|-CS1FX|-CS3FX|SA2|SA1|SA0| Read (-IOR) | Write (-IOW) |
+----+------+------+---+---+---+----------------+---------------+-----------+
| | 0 | 0 | X | X | X | ILLEGAL | ILLEGAL | <--+ |
| | 1 | 1 | X | X | X | High Impedance | Not Used | Control |
|3FX | 1 | 0 | 0 | X | X | High Impedance | Not Used | Block |
|3FX | 1 | 0 | 1 | 0 | X | High Impedance | Not Used | Registers |
|3F6 | 1 | 0 | 1 | 1 | 0 | Altern Status | Device Control| | |
|3F7 | 1 | 0 | 1 | 1 | 1 | Drive Address | Not Used | <--+ |
+----+------+------+---+---+---+----------------+---------------+-----------+
|1F0 | 0 | 1 | 0 | 0 | 0 | Data Port | Data Port | <--+ |
|1F1 | 0 | 1 | 0 | 0 | 1 | Error Register | Precomp | | |
|1F2 | 0 | 1 | 0 | 1 | 0 | Sector Count | Sector Count | Command |
|1F3 | 0 | 1 | 0 | 1 | 1 | Sector Number | Sector Number | Block |
|1F4 | 0 | 1 | 1 | 0 | 0 | Cylinder Low | Cylinder Low | Registers |
|1F5 | 0 | 1 | 1 | 0 | 1 | Cylinder High | Cylinder High | | |
|1F6 | 0 | 1 | 1 | 1 | 0 | Drive / Head | Drive / Head | | |
|1F7 | 0 | 1 | 1 | 1 | 1 | Status | Command | <--+ |
+----+------+------+---+---+---+----------------+---------------+-----------+
在加电或者复位后, 命令寄存器组被初始化成如下值:
REGISTER VALUE
1F1 Error : 01
1F2 Sector Count : 01
1F3 Sector Number : 01
1F4 Cylinder Low : 00
1F5 Cylinder High : 00
1F6 Drive / Head : 00
1F0: Read/Write: 数据端口寄存器
host和设备的数据传输通过这个寄存器进行. 也用于格式化时传输扇区表,在执行Read/Write
Long commands时传输8 bit 的ECC数据.
1F1: Read: 错误码寄存器
最后一次命令执行的状态信息.仅当状态寄存器的ERR位置位时此寄存器有效.
在加电和内部自检后此寄存器包含一个状态码.当状态寄存器的error位置位时此寄存器含义如下:
+-----+--------+-------------------------------------------------------------+
| BIT | Mnemon | Description |
+-----+--------+-------------------------------------------------------------+
| 7 | BBK | Bad block mark detected in the requested sector's ID field |
| 6 | UNC | Uncorrectable data error encountered |
| 5 | | Not used |
| 4 | IDNF | Requested sector's ID field not found |
| 3 | | Not used |
| 2 | ABRT | Command aborted due to drive status error or invalid command|
| 1 | TK0NF | Track 0 not found during execution of Recalibrate command |
| 0 | AMNF | Data address mark not found after correct ID field found |
+-----+--------+-------------------------------------------------------------+
1F1: Write: 写补偿
驱动忽略此寄存器.
1F2: Read/Write: 扇区计数
定义数据传输的扇区数量, 后续的命令里,如果此值是0 代表 256 个扇区.
如果命令执行成功,最后在这个寄存器里的值是0. 每一个扇区传输以后,
寄存器内的值减1,寄存器内的值代表了剩余要传输的扇区数目. 如果命令执行未成功,
寄存器内包含要完成这次传输还必须要传输的扇区数目.
1F3: Read/Write: 首扇区编号
包含传输的第一个扇区的ID. 从1 到每个磁道的最大值.
1F4: Read/Write: 柱面低8位
如果访问操作跨越柱面,其值自动增1,以反映当前柱面.
1F5: Read/Write: 柱面高8位
同1f4
1F6: Read/Write: 驱动器/磁头选择
数据格式如下:
+-----+----------+---------------------------------------------------------+
| BIT | Mnemonic | Description |
+-----+----------+---------------------------------------------------------+
| 7 | Reserved | 恒为 1 |
| 6 | Reserved | 恒为 0 |
| 5 | Reserved | 恒为 1 |
| 4 | DRV | 0 to select primary drive, 1 to select secondary drive. |
| 3 | HS3 | MSB of head number. |
| 2 | HS2 | |
| 1 | HS1 | |
| 0 | HS0 | LSB of head number. |
+-----+----------+---------------------------------------------------------+
Upon command completion this register is updated to refplect the head number currently
selected.
1F7: Read: 状态寄存器
在每一个命令执行完成之后驱动器更新这个寄存器反映当前设备状态. 如果busy bit 置位,
其他位都是无效的.如果没有置位其格式如下:
+-----+----------+----------------------------------------------------------+
| BIT | Mnemonic | Description |
+-----+----------+----------------------------------------------------------+
| 7 | BUSY | Busy bit. Set by the controller logic of the drive when |
| | | ever the drive has access to and the host is locked out |
| | | of the Command Block Registers. Set under the following |
| | | conditions: |
| | | o Within 400 nsec after the negation of RESET or after |
| | | SRST is set in the Device Control Register. After a |
| | | reset it is recomended that BUSY be set no more than |
| | | 30 seconds. |
| | | o Within 400 nsec of a host write to the Command |
| | | Register with a Recalibrate, Read Long, Read Buffer, |
| | | Read, Read Verify, Initialize Drive Parameters, Seek |
| | | Identify Drive, or Execute Drive Diagnostic command. |
| | | o Within 5 microseconds following the transfer of 512 |
| | | bytes of data during the execution of a Write, Write |
| | | Buffer or Format Track command; or 512 bytes of data |
| | | and the appropriate number of ECC bytes during the |
| | | execution of a Write Long command. |
| | | When BUSY is set no Command Block Register can be |
| | | written too and a read of any Command Block Register |
| | | returns the contents of the Status Register. |
| | | |
| 6 | DRDY | Drive Ready bit. Indicates that the drive is ready to |
| | | accept commands. When and error occurs, this bit stays |
| | | unchanged until the host reads the Status Register then |
| | | again indicates that hte drive is ready. On power up, |
| | | this bit should be cleared and should remain cleared |
| | | until the drive is up to speed and ready to accept a |
| | | command. |
| | | |
| 5 | DWF | Drive Write Fault bit. When an error occurs, this bit |
| | | remains unchanged until the host reads the Status |
| | | Register, then again indicates the current write fault |
| | | status. |
| | | |
| 4 | DSC | Drive Seek Complete bit. This bit is set when a seek |
| | | operation is complete and the heads are settled over a |
| | | track. When an error occurs, this bit remains unchanged |
| | | until the host reads the Status Register, then again it |
| | | indicates the current seek complete status. |
| | | |
| 3 | DRQ | Data Request bit. When set it indicates that the drive |
| | | is ready to transfer a word or byte of data between the |
| | | host and the data port. |
| | | |
| 2 | CORR | Corrected Data bit. When a correctable data error has |
| | | been encountered and the data has been corrected, this |
| | | bit is set. This condition does not terminate a multi |
| | | sector read operation. |
| | | |
| 1 | INDEX | Index bit. Set when the index mark is detected once per |
| | | disk revolution. |
| | | |
| 0 | ERROR | Error bit. When set indicates that the previous command |
| | | ended in an error. The other bits in the Error Register |
| | | and Status Register contain additional information about |
| | | the cause of the error. |
+-----+----------+----------------------------------------------------------+
1F7: Write: 命令寄存器
一旦命令写入寄存器,设备就开始执行这个命令.下面的表是各种命令和命令参数.
+--------+---------------------------------+-----------------+
| Command| Command Description | Parameters Used |
| Code | | PC SC SN CY DH |
+--------+---------------------------------+-----------------+
| 98h @ | Check Power Mode | V D |
| E5h @ | Check Power Mode (same as 98h) | V D |
| 90h | Execute Drive Diagnostic | D+ |
| 50h | Format Track | V V |
| ECh @ | Identify Drive | D |
| 97h @ | Idle | V D |
| E3h @ | Idle (same as 97h) | V D |
| 95h @ | Idle Immediate | D |
| E1h @ | Idle Immadiate (same as 95h) | D |
| 91h | Initialize Drive Parameters | V V |
| E4h @ | Read Buffer | D |
| C8h @ | Read DMA With Retry | >> Unknown << |
| C9h @ | Read DMA | >> Unknown << |
| C4h @ | Read Multiple | V V V V |
| 20h | Read Sectors With Retry | V V V V |
| 21h | Read Sectors | V V V V |
| 22h | Read Long With Retry | V V V V |
| 23h | Read Long | V V V V |
| 40h | Read Verify Sectors With Retry | V V V V |
| 41h | Read Verify Sectors | V V V V |
| 1Xh | Recalibrate | D |
| 7Xh | Seek | V V |
| EFh @ | Set Features | V D |
| C6h @ | Set Multiple Mode | V D |
| 99h @ | Set Sleep Mode | D |
| E6h @ | Set Sleep Mode (same as 99h) | D |
| 96h @ | Standby | V D |
| E2h @ | Standby (same as 96h) | V D |
| 94h @ | Standby Immediate | D |
| E0h @ | Standby Immediate (same as 94h) | D |
| 8Xh | Vendor Unique | >> Unknown << |
| 9Ah | Vendor Unique | >> Unknown << |
| C0h | Vendor Unique | >> Unknown << |
| C1h | Vendor Unique | >> Unknown << |
| C2h | Vendor Unique | >> Unknown << |
| C3h | Vendor Unique | >> Unknown << |
| F5h | Vendor Unique | >> Unknown << |
| F6h | Vendor Unique | >> Unknown << |
| F7h | Vendor Unique | >> Unknown << |
| F8h | Vendor Unique | >> Unknown << |
| F9h | Vendor Unique | >> Unknown << |
| FAh | Vendor Unique | >> Unknown << |
| FBh | Vendor Unique | >> Unknown << |
| FCh | Vendor Unique | >> Unknown << |
| FDh | Vendor Unique | >> Unknown << |
| FEh | Vendor Unique | >> Unknown << |
| FFh | Vendor Unique | >> Unknown << |
| E8h @ | Write Buffer | D |
| CAh @ | Write DMA With Retry | >> Unknown << |
| CBh @ | Write DMA | >> Unknown << |
| C5h @ | Write Multiple | V V V V |
| E9h @ | Write Same | >> Unknown << |
| 30h | Write Sectors With Retry | V V V V |
| 31h | Write Sectors | V V V V |
| 32h | Write Long With Retry | V V V V |
| 33h | Write Long | V V V V |
| 3Ch @ | Write Verify | V V V V |
+--------+---------------------------------+-----------------+
KEY FOR SYMBOLS IN ABOVE TABLE:
PC Register 1F1: Write Precompensation
SC Register 1F2: Sector Count
SN Register 1F3: Sector Number
CY Register 1F4+1F5: Cylinder low + high
DH Register 1F6: Drive / Head
@ These commands are optional and may not be supported by some drives.
D Only DRIVE parameter is valid, HEAD parameter is ignored.
D+ Both drives execute this command regardless of the DRIVE parameter.
V Indicates that the register contains a valid paramterer.
Commands with >> Unknown << Parameters are not described in this
document.
If a parameter is blank, then the command does not require the contents of that
register.
3F6: Read: Alternate Status Register
Contains the same information as the Status Register in the Command Block. Reading the
Alternate Status Register does not imply an interrupt acknowledge from the host or
clear a pending interrupt. See the description of the Status Register above for a
definition of bits in this register.
3F6: Write: Device Control Register
The bits in the Device Control Register are lister in the table below:
+-----+----------+----------------------------------------------------------+
| BIT | Mnemonic | Description |
+-----+----------+----------------------------------------------------------+
| 7 | Reserved | |
| 6 | Reserved | |
| 5 | Reserved | |
| 4 | Reserved | |
| 3 | 1 | Always set. |
| 2 | SRST | Host Software Reset bit. When this bit is set the drive |
| | | is held reset. If two drives are daisy chained on the |
| | | interface, this bit resets both drives simultaneously. |
| | | |
| 1 | nIEN | Drive Interrupt Enable bit. The enable bit for the drive |
| | | interrupt to the host. When nIEN is 0 or the drive is |
| | | selected the host interrupt signal INTRQ is enabled |
| | | through a tri state buffer to the host. When nIEN is 1 |
| | | or the drive is not selected the host interrupt signal |
| | | INTRQ is in a hig himpedance state regardless of the |
| | | presence or absence of a pending interrupt. |
| | | |
| 0 | 0 | Always clear. |
+-----+----------+----------------------------------------------------------+
3F7: Read: 驱动器地址状态寄存器
含有当前选择的驱动器和磁头的值. 含义如下:
+-----+----------+------------------------------------------------------+
| BIT | Mnemonic | Description |
+-----+----------+------------------------------------------------------+
| 7 | HiZ | This bit is in high impedance when read. |
| 6 | nWTG | Write Gate bit. When a write to the hard drive is in |
| | | progress, nWTG is 0 |
| 5 | nHS3 | Negated MSB of head number |
| 4 | nHS2 | |
| 3 | nHS1 | |
| 2 | nHS0 | Negated LSB of head number. |
| 1 | nDS1 | Drive 1 Select bit. When 0, Drive 1 is selected. |
| 0 | nDS0 | Drive 0 Select bit. When 0, Drive 0 is selected. |
+-----+----------+------------------------------------------------------+