ISD-200 Datasheet, PDF (28/64 Pages) List of Unclassifed Manufacturers – USB Mass Storage Class Bulk-Only Specification Compliant

ISD-200 ASIC Datasheet
Address
Field Name
0x13D
0x13E
bString
bString
0x13F bString
* - First Silicon value
** - Second Silicon value
Table 11 – String Descriptors
Description
On-board
Defaults
0x00
* 0x32
** 0x33
0x00
ATA/ATAPI Interface
The ATA/ATAPI port on the ISD-200 is compliant with the Information Technology – AT Attachment with
Packet Interface – 4 (ATA/ATAPI-4) Specification, T13/1153D Rev 18
(ftp://fission.dt.wdc.com/x3t13/project/d1153r18.pdf). The ISD-200 provides support for Packet commands
as well as ATA commands. The ISD-200 provides a vendor-specific Identify (FBh) command that returns
configuration data and USB descriptor information (see Descriptors section, page 7) from an attached
mass storage device. Additionally, there is a built in vendor-specific event notify command to
communicate certain events on an interrupt basis to the device.
Protocol
The ISD-200 supports command protocol flows as defined in the ATA/ATAPI-4 Specification. Commands
are grouped into different classes, based on the protocol followed for command execution.
The ATA/ATAPI interface supports the following clarifications:
• Immediately after the reset recovery period, the ISD-200 will write 0x00 to the Device Control
register.
• Arbitrary byte count transfers supported.
• 16-bit data reads and writes. 8-bit data transfers not supported.
Reset Mapping
The ATA/ATAPI Interface responds to several resets, Power-on, Resume, USB, MSC Hard, and Vendor-
specific Soft reset.
In the case of a Power-on reset, a full device initialization is performed (See Figure 3). FBh data is
retrieved and stored if applicable. In the case of a Resume reset, a full device initialization is performed as
well (previously stored FBh data is not effected).
In the cases of USB reset and MSC Hard reset, a partial initialization is performed which excludes all
attempts to perform Identify Device commands. If BUS_POWER=1 then the USB reset causes a full
initialization after the USB configuration setting is restored.
In the case of a Vendor-specific Soft reset, only the internal state machines are reset.
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In-System Design Confidential