LSI Symbios SYM53C040, Technical Manual

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6-6 Two-Wire Serial Registers
STA Start 2
When set, this bit signifies that the byte located in the
Two-Wire Register 0xFD00/0xFD02 [(ES0, ES1, ES2 =
100] - Data Register) will be sent out on the Two-Wire
Serial bus with a start condition as defined in the I
2
C
specification.
STO Stop 1
When set, this bit signifies that a stop condition (as
described in the I
2
C specification) will be sent out onto
the interface.
ACK Acknowledge 0
When set, this bit will enable an ACK to be transmitted
during the ninth clock cycle of the transfer after receiving
a data byte.
Register: 0xFD01/0xFD03
Control Register Reads (ES0 = 0)
Read Only
PIN Pending Interrupt 7
Setting this bit clears the interrupt and all of the status
bits.
ES0 Enable Serial Output 6
This bit enables the Two-Wire Serial bus I/O. When low
(0), register access is available for initialization. If high
(1), then the serial shift register S0 and status register S1
are accessible.
7 6 5 4 3 2 1 0
PIN ES0 ES1 ES2 ENI STA STO ACK
Defaults:
0 0 0 0 0 0 0 0