參數(shù)資料
型號: FDC37C665GT
廠商: STANDARD MICROSYSTEMS CORP
元件分類: 存儲控制器/管理單元
英文描述: High-Performance Multi-Mode Parallel Port Super I/O Floppy Disk Controllers
中文描述: 1 Mbps, IDE COMPATIBLE, FLOPPY DISK DRIVE CONTROLLER, PQFP100
封裝: QFP-100
文件頁數(shù): 70/162頁
文件大?。?/td> 562K
代理商: FDC37C665GT
70
different cylinder results which may be difficult
to keep track of with software without the Read
ID command.
Perpendicular Mode
The Perpendicular Mode command should be
issued prior to executing Read/Write/Format
commands that access a disk drive with
perpendicular recording capability. With this
command, the length of the Gap2 field and VCO
enable timing can be altered to accommodate
the unique requirements of these drives. Table
31 describes the effects of the WGATE and
GAP bits for the Perpendicular Mode command.
Upon a reset, the FDC will default to the
conventional mode (WGATE = 0, GAP = 0).
Selection of the 500 Kbps and 1 Mbps
perpendicular modes is independent of the
actual data rate selected in the Data Rate Select
Register. The user must ensure that these two
data rates remain consistent.
The Gap2 and VCO timing requirements for
perpendicular recording type drives are dictated
by the design of the read/write head. In the
design of this head, a pre-erase head precedes
the normal read/write head by a distance of 200
micrometers. This works out to about 38 bytes
at a 1 Mbps recording density. Whenever the
write head is enabled by the Write Gate signal,
the pre-erase head is also activated at the same
time. Thus, when the write head is initially
turned on, flux transitions recorded on the media
for the first 38 bytes will not be preconditioned
with the pre-erase head since it has not yet been
activated. To accommodate this head activation
and deactivation time, the Gap2 field is
expanded to a length of 41 bytes. The format
field shown on page 66 illustrates the change in
the Gap2 field size for the perpendicular format.
On the read back by the FDC, the controller
must begin synchronization at the beginning of
the sync field. For the conventional mode, the
internal PLL VCO is enabled (VCOEN)
approximately 24 bytes from the start of the
Gap2 field. But, when the controller operates in
the 1 Mbps perpendicular mode (WGATE = 1,
GAP = 1), VCOEN goes active after 43 bytes to
accommodate the increased Gap2 field size.
For both cases, and approximate two-byte
cushion is maintained from the beginning of the
sync field for the purposes of avoiding write
splices in the presence of motor speed variation.
For the Write Data case, the FDC activates
Write Gate at the beginning of the sync field
under the conventional mode. The controller
then writes a new sync field, data address mark,
data field, and CRC as shown in Figure 4. With
the pre-erase head of the perpendicular drive,
the write head must be activated in the Gap2
field to insure a proper write of the new sync
field. For the 1 Mbps perpendicular mode
(WGATE = 1, GAP = 1), 38 bytes will be written
in the Gap2 space. Since the bit density is
proportional to the data rate, 19 bytes will be
written in the Gap2 field for the 500 Kbps
perpendicular mode (WGATE = 1, GAP =0).
It should be noted that none of the alterations in
Gap2 size, VCO timing, or Write Gate timing
affect normal program flow. The information
provided here is just for background purposes
and is not needed for normal operation. Once
the Perpendicular Mode command is invoked,
FDC software behavior from the user standpoint
is unchanged.
The perpendicular mode command is enhanced
to allow specific drives to be designated
Perpendicular
recording
enhancement allows data transfers between
Conventional and Perpendicular drives without
having to issue Perpendicular mode commnds
between the accesses of the different drive
types, nor having to change write pre-
compensation values.
drives.
This
相關(guān)PDF資料
PDF描述
FDC37C666GT High-Performance Multi-Mode Parallel Port Super I/O Floppy Disk Controllers
FDC37C67X ENHANCED SUPER I/O CONTROLLER WITH FAST IR
FDC37C957FR ULTRA I/O CONTROLLER FOR PORTABLE APPLICATIONS
FDC37M600 ENHANCED SUPER I/O CONTROLLER WITH INFRARED SUPPORT
FDC37M601 ENHANCED SUPER I/O CONTROLLER WITH INFRARED SUPPORT
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
FDC37C665GT_07 制造商:SMSC 制造商全稱:SMSC 功能描述:High-Performance Multi-Mode Parallel Port Super I/O Floppy Disk Controllers
FDC37C665GT-MS 功能描述:輸入/輸出控制器接口集成電路 Super I/O Controller- Pb Free RoHS:否 制造商:Silicon Labs 產(chǎn)品: 輸入/輸出端數(shù)量: 工作電源電壓: 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-64 封裝:Tray
FDC37C665GTQFP 功能描述:輸入/輸出控制器接口集成電路 Super I/O Controller RoHS:否 制造商:Silicon Labs 產(chǎn)品: 輸入/輸出端數(shù)量: 工作電源電壓: 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-64 封裝:Tray
FDC37C665IR 制造商:SMSC 制造商全稱:SMSC 功能描述:3/5 Volt Advanced High-Performance Multi-Mode Parallel Port Super I/O Floppy Disk Controller with Infranred Support
FDC37C665IRQFP 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:SMSC 功能描述: