COM20020-5 Datasheet, PDF (26/58 Pages) SMSC Corporation – Universal Local Area Network Controller with 2K x 8 On-Board RAM

TABLE 6 - ADDRESS POINTER HIGH REGISTER
BIT
BIT NAME
SYMBOL
DESCRIPTION
7 Read Data
RDDATA
This bit tells the COM20020-5 whether the following
access will be a read or write. A logic "1" prepares the
device for a read, a logic "0" prepares it for a write.
6 Auto Increment
AUTOINC
This bit controls whether the address pointer will
increment automatically. A logic "1" on this bit allows
automatic increment of the pointer after each access,
while a logic "0" disables this function. Please refer to
the Sequential Access Memory section for further detail.
5-3 (reserved)
These bits are undefined.
2-0 Address 10-8
A10-A8
These bits hold the upper three address bits which
provide addresses to RAM.
BIT
7-0
TABLE 7 - ADDRESS POINTER LOW REGISTER
BIT NAME
SYMBOL
DESCRIPTION
Address 7-0
A7-A0
These bits hold the lower 8 address bits which provide
the addresses to RAM. Writing to the Address Pointer
Low sets the address, so the Address Pointer High
should be written before Address Pointer Low.
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