OXCF950_06 Datasheet, PDF (54/66 Pages) Oxford Semiconductor – low cost asynchronous 16-bit PC card or Compact Flash UART device

OXFORD SEMICONDUCTOR, INC.
OXCF950 rev B DATA SHEET
Bits
Description
15:4
These bits should return 0xB12 to identify a valid program.
Once it reads this value from these bits it sets bit [TBD] in the
TBD register in the local register.
3
Reserved
2
1 = Zone 1 (CIS Configuration) data exists
0 = Zone 1 does not exist
1
1 = Zone 2 (Local Register Configuration) data exists
0 = Zone 2 does not exist
0
1 = Zone 3 (Function Access) data exists
0 = Zone 3 does not exist
Table 42: Zone 0 format
The programming data for each zone follows the
proceeding zone if it exists (again note order is zone 0, 2,
1, 3). For example a header value of 0xB127 indicates that
all zones exist, while 0XB123 indicates that only zone 2
and zone 3 exist.
7.3 Zone 1: Card Information Structure
This zone allows the user to provide custom tuple
information for the Card Information Structure (CIS),
overriding the default hard-coded tuple values found in the
device. Downloading into this zone programs the internal
RAM with the user’s tuple data and automatically sets the
source of the CIS to be this RAM, and not the hard coded
value.
Note: if the CIS is to be modified using the EEPROM,
tuple values presented to the host will be those
programmed into the RAM. The user must ensure that
the RAM contains all the correct tuples for the
particular application.
Tuple data bytes are interrogated until the specified
number of type data-bytes have been collected in which
case the EEPROM moves over to the next zone if it exists,
or the EEPROM download terminates if no other zones are
present.
The zone contains two areas to download to:
• Attribute memory (RAM address (0 to 127)
• Common memory (RAM address (128 to 255)
Usually all tuple data is held in attribute memory, but some
applications may use common memory as well.
The first WORD in this zone describes how many bytes of
data are present in each zone. The next words contain the
tuple data. The first set of WORDS contain the tuples for
the common memory (if present) followed by the tuple
WORDS for the attribute memory.
If the tuple data is an odd number of bytes it should be
padded at the end with an additional ‘FF’.
Byte Number
1^st WORD
2^nd WORD
3^rd WORD
(N + 1) th WORD
(N + 2) th WORD
(N + 3) th WORD
(N + M + 1) th WORD
Description
15
87
0
Number of tuple bytes in Common Memory (N) Number of tuple bytes in Attribute Memory (M)
Note : Must be a value of multiple of 2
Note : Must be a value of multiple of 2
Attribute Mem.Tuple Byte 1
Attribute Mem.Tuple Byte 0
Attribute Mem.Tuple Byte 3
Attribute Mem.Tuple Byte 2
Attribute Mem.Tuple Byte N-1
Attribute Mem.Tuple Byte N-2
Common Mem. Tuple Byte 1
Common Mem. Tuple Byte 0
Common Mem. Tuple Byte 3
Common Mem. Tuple Byte 2
Common Mem. Tuple Byte M-1
Common Mem. Tuple Byte M-2
Table 43: Word format for Zone 1
7.4 Zone 2: Local Register Configuration
The Zone 2 region of EEPROM contains the program value of the vendor-specific Local Configuration Registers using one or
more configuration WORDs. Registers are selected using a 7-bit byte-offset field. This offset value is the offset from address 8
(allowing addresses 0 to 7 to be reserved for function access).
DS-0027 Feb 06
External—Free Release
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