SanDisk SD25B-100, Руководство по эксплуатации продукта

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FlashDrive Product Manual
FlashDrive Product Manual © 1999 SANDISK CORPORATION 25
4.2 Electrical Description
The IDE interface between the SanDisk
FlashDrive and the host is a subset of the
standard PC/AT I/O Interface. It differs from the
original PC/AT in that the address port decode is
not resident in the SanDisk IDE FlashDrives. Table 4-2 describes the I/O signals. Signals whose
source is the host are designated as inputs while
signals that the FlashDrive sources are outputs.
Refer to section 4.3 for definitions of Input and
Output type.
Table 4-2 Signal Descriptions
Signal Name Dir Pin Description
-SLAVE I B,C
(Except
SD35B
3.5-inch
FlashDrive)
SLAVE Mode
Pins B and C are pulled-up input pins that are shorted together
internally. (Pins A and D are ground.) These pins are used to
configure the FlashDrive as a Slave device. When either pin B or pin
C is grounded by the user, either using a shunt jumper or through a
ground on the host motherboard if a 50 pin connector is used, the
FlashDrive is configured as a Slave device. If both pins B and C
remain open, the FlashDrive is configured as a Master in a
Master/Slave configuration or as the only drive in a single drive
system.
-RESET I 1 HOST RESET
Reset signal from the host that is active on power up and inactive
thereafter.
Data (15-0) I/O 18,16,14,12,
10,8,6,4,
3,5,7,9,11,
13,15,17
HOST DATA (15-0)
These 16 lines carry the Data between the controller and the host.
The low 8 lines transfer commands, status and ECC information
between the host and the controller.
-IOW I 23 I/O WRITE
This strobe pulse is used to clock data or commands on the host
data bus into the controller. The clocking will occur on the negative
to positive edge of the signal (trailing edge).
-IOR I 25 I/O READ
This is a read strobe generated by the host. This signal gates data
or status on the host bus and strobes the data from the controller
into the host on the low to high transition (trailing edge).
IRQ O 31 INTERRUPT REQUEST
This is an interrupt request from the controller to the host, asking for
service. The output of this signal is tri-stated when the interrupts
are disabled by the host.
-IOCS16 O 32 I/O SELECT 16
This open drain output is asserted low by the controller to indicate to
the host the current cycle is a 16 bit word data transfer.
-PDIAG I/O 34 PASS DIAGNOSTIC.
This bi-directional open drain signal is asserted by the slave after an
Execute Diagnostic command to indicate to the master it has
passed it’s diagnostics.
A(2-0) I 36,33,35 HOST ADDRESS (2-0)
These address lines are used to select the registers within the
controller task file.