參數(shù)資料
型號(hào): 37C669
廠商: SMSC Corporation
英文描述: DIODE SCHOTTKY SINGLE 25V 200mW 0.5V-vf 200mA-IFM 30mA-IF 2uA-IR SOD-323 3K/REEL
中文描述: 電腦98/99順從超級(jí)I / O軟盤(pán)控制器與紅外線(xiàn)支持
文件頁(yè)數(shù): 130/164頁(yè)
文件大?。?/td> 621K
代理商: 37C669
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)第117頁(yè)第118頁(yè)第119頁(yè)第120頁(yè)第121頁(yè)第122頁(yè)第123頁(yè)第124頁(yè)第125頁(yè)第126頁(yè)第127頁(yè)第128頁(yè)第129頁(yè)當(dāng)前第130頁(yè)第131頁(yè)第132頁(yè)第133頁(yè)第134頁(yè)第135頁(yè)第136頁(yè)第137頁(yè)第138頁(yè)第139頁(yè)第140頁(yè)第141頁(yè)第142頁(yè)第143頁(yè)第144頁(yè)第145頁(yè)第146頁(yè)第147頁(yè)第148頁(yè)第149頁(yè)第150頁(yè)第151頁(yè)第152頁(yè)第153頁(yè)第154頁(yè)第155頁(yè)第156頁(yè)第157頁(yè)第158頁(yè)第159頁(yè)第160頁(yè)第161頁(yè)第162頁(yè)第163頁(yè)第164頁(yè)
68
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 61 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
drives.
This
enhancement allows data transfers between
Conventional and Perpendicular drives without
having to issue Perpendicular mode commands
between the accesses of the different drive
types,
nor
having
to
change
write
pre-
compensation values.
相關(guān)PDF資料
PDF描述
37C672 ENHANCED SUPER I/O CONTROLLER WITH FAST IR
37C67X ENHANCED SUPER I/O CONTROLLER WITH FAST IR
37C957FR ULTRA I/O CONTROLLER FOR PORTABLE APPLICATIONS
37FMA1-ABW31N SPECIAL SWITCH-PIEZO SWITCH, SPST, MOMENTARY, 0.2A, 24VDC, PANEL MOUNT-THREADED
37FML1-BEW31N SPECIAL SWITCH-PIEZO SWITCH, SPST, MOMENTARY, 0.2A, 24VDC, PANEL MOUNT-THREADED
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
37C672 制造商:SMSC 制造商全稱(chēng):SMSC 功能描述:ENHANCED SUPER I/O CONTROLLER WITH FAST IR
37C67X 制造商:SMSC 制造商全稱(chēng):SMSC 功能描述:ENHANCED SUPER I/O CONTROLLER WITH FAST IR
37C-6BH-5-5 制造商:Birtcher Products 功能描述:
37C72U-185 制造商:White-Rodgers 功能描述:
37C73U-170 制造商:White-Rodgers 功能描述: