IDT 89HPES24N3A, User Manual

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IDT Configuration Registers
PES24N3A User Manual 9 - 57 April 10, 2008
Notes
IOEXPINTF - I/O Expander Interface (0x430)
25 DONE RW1C 0x0 EEPROM Operation Completed. This bit is set when a
serial EEPROM operation has completed.
0x0 -(notdone) interface is idle or operation in progress
0x1 -(done) operation completed
26 OP RW 0x0 EEPROM Operation Select. This field selects the type of
EEPROM operation to be performed when the DATA field is
written
0x0 -(write) serial EEPROM write
0x1 -(read) serial EEPROM read
31:27 Reserved RO 0x0 Reserved field.
Bit
Field
Field
Name
Type
Default
Value
Description
15:0 IOEDATA RW 0x0 I/O Expander Data. Each bit in this field corresponds to an
I/O expander input/output signal. Reading this field returns
the current value of the corresponding I/O pin state of the I/
O expander number selected in the Select (SEL) field in this
register (i.e., the input values last read from the I/O
expander and output values supplied to the I/O expander).
Writes to this field are ignored unless the I/O Expander Test
Mode (IOEXTM) bit is set. When the IOEXTM bit is set, the
value for outputs supplied to the I/O expander selected by
the SEL field correspond to the value written to this field
instead of the value supplied by internal logic. Bits in this
field which correspond to inputs are always read-only, even
when the IOEXTM bit is set.
23:16 Reserved RO 0x0 Reserved field.
24 RELOADI-
OEX
RW 0x0 Reload I/O Expander Signals. Writing a one to this field
results in an I/O expander SMBus transaction that refreshes
all I/O expander input and output signal values in the
IOEDATA field. This bit always returns a zero when read.
25 IOEXTM RW 0x0 IO Expander Test Mode. Setting this bit puts the I/O
expander interface into a test mode. In this test mode, I/O
expander output signals generated by the PES24N3A core
are ignored and values supplied to the I/O expander corre-
spond to value written to the IOEDATA field.
27:26 Reserved RO 0x0 Reserved field.
30:28 SELECT RW 0x0 I/O Expander Select. This field selects the I/O expander on
which fields in this register operate.
0x0 - (oe0) I/O expander 0
0x1 - reserved
0x2 - (ioe2) I/O expander 2
0x3 - reserved
0x4 - (ioe4) I/O expander 4
0x5 through 0x7 - reserved
Bit
Field
Field
Name
Type
Default
Value
Description