pl-3507d-lf Prolific Technology Inc., pl-3507d-lf Datasheet - Page 14

• Manufacturer Part Number: pl-3507d-lf
• Description: Pl-3507 For Chip Rev D Hi-speed Usb & Ieee 1394 Combo To Ide Bridge Controller
• Manufacturer: Prolific Technology Inc.

Revised Date:
August 28, 2007
ds_pl3507D_v1.1.doc
7.0 Functional Description
7.1
General Function
The PL-3507 is a combined USB 2.0 and 1394 to ATA/ATAPI bridge controller for connecting host
computers to IDE storage devices like Hard Disk and Optical Disk Drive. The PL-3507 has auto-detect
capability to provide connections either from USB to ATA/ATAPI or 1394 to ATA/ATAPI devices.
The CPU program code comes from the internal ROM code (Chip Rev 2D only) or external flash
device. During power-on of device, the PL-3507 hardware will automatically detect the availability of an
external flash device to load the firmware program code instead of the chip internal ROM code.
The external program storage device used are shadowed into internal program SRAM during power on
or active device switching, where the instruction codes of “USB “ and “1394” reside in address location
“0000h~5fffh” and “8000h~efffh” separately in the external program devices. At the power on moment,
active device is determined by the state of input pin “EXTSEL_USB”, if it’s logic one, the 24k byte
instruction codes of external program memory starting from location 0000h will be loaded into internal
program memory, otherwise the instruction codes starting from location 8000h will be loaded. When
active device is switching due to USB or 1394 cable connection status changes, the corresponding
instruction code will be loaded into internal program memory before reset ends.
Only one interface (USB or 1394) can be active at a time to be used for transferring data between host
computer and ATA/ATAPI devices. When both two interfaces are connected to the host computer, a
“first-come-first-serve” algorithm is used to select the active device. The connection detection of both
two interfaces are through cable power from USB cable and 1394 cable, when the connection status
changes, interrupts will happen via INT1 to inform the firmware. If both two interfaces (USB and 1394)
are connected before power-on, the status of pin “EXTSEL_USB” will determine which interface (USB
or 1394) will be active after power-on, if the logic value of “EXTSEL_USB” is one, USB will be the
active device, otherwise 1394 will be the active device.
When connecting to host computers through 1394 cable, host will read configuration ROM from the
PL-3507 in order to be recognized as a SBP2 storage device, and then host will send login request
packets via management ORBs to complete login process. After login is finished, the host computer
can start to transfer data to/from ATA/ATAPI devices through the PL-3507 by command ORB packets.
The PL-3507 has built in a SBP2 hardware engine that can enhance data transfer rate up to 36
Mbytes/sec.
When connecting to host computers through USB cable, host computer will get device descriptor from
the PL-3507 in order to be recognized as a mass storage class device, and then the host can start to
transfer data to/from ATA/ATAPI devices through the PL-3507.
PL-3507D Product Datasheet
- 14 -
Document Version 1.1