OXCFU950_07 Datasheet, PDF (16/74 Pages) Oxford Semiconductor – USB/UART multi-function 16-bit PC Card device

OXFORD SEMICONDUCTOR, INC.
OXCFU950 DATA SHEET
6 PC CARD & COMPACTFLASH/CF+ TARGET CONTROLLER
6.1 Operation
Note: See section 14 for timing waveforms.
The OXCFU950 responds to a number of different 16-bit PC Card/CompactFlash accesses (detailed below). Section 14 contains
timing diagrams and information for each of these types of access:
• Direct common memory read/writes: These are required to gain access to the 8 Kbytes of RAM used by the OHCI USB host
controller.
• Direct attribute memory read/writes: Access to direct attribute memory is required to allow the host access to both the CIS
and FCRs (for each function). Valid data is 8 bits wide and on even bytes only, for direct attribute memory.
• I/O read/writes: I/O accesses are performed to access the USB host controller, UART and local configuration registers. Data
width is restricted to 8 bits, as required by the standard UART function. While the device CIS information configures the card
as a multifunction device, the host (or device driver/EEPROM controller) must set up a base address within I/O space for
each function. As reads and writes are immediate, there is no requirement to hold the WAIT# signal in its active state, thus
providing maximum speed access to I/O space.
6.2 OXCFU950 Memory Space Map
Attribute Memory
Function 1 - Function
Configuration Registers
(Base Address 0x300)
Function 0 - Function
Configuration Registers
(Base Address 0x200)
CIS
The CIS is programmed from
EEPROM and therefore not
of a fixed size.
It's maximum size is 256
bytes addressable on even
locations between 0x000 and
0x1FE
Common Memory
USB host RAM
The actual RAM is 8 Kbytes
in size.
This area of memory is only 2
Kbytes in size (a limitation of
the size of the Compact
Flash address bus).
A paging mechanism is
therefore used to allow
access to the full 8 Kbytes
Host I/O Space
Function 0 I/O Window
Up to 64 bytes of I/O space.
Can be placed anywhere by
host
Function 1 I/O Window
Up to 64 bytes of I/O space.
Can be placed anywhere by
host
DS-0023 February 2007
External—Free Release
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