MOGlabs ARF021, Руководство пользователя

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8.3 Digital I/O
61
Figure 8.2:
Example of table mode, showing changing RF output (blue,
lower trace) and synchronised TTL output (red, upper trace) generated by
the example in Listing 8.2.
bit corresponds to a pin of the high-speed output banks. If a bit is
set in the
IOMASK
value, then the corresponding value of
IOSET
is
written to that pin, overwriting any previous value. This allows all
pins of both high-speed banks to be changed in each table entry, or
only a subset of the pins. Table 8.1 demonstrates an example that
simultaneously writes 5 pins of bank A and 4 pins of bank B.
Bank B Bank A
Bit 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
IOSET 0 0 1 0 1 1 1 1 1 0 0 1 0 0 1 1
IOMASK 0 1 0 0 1 1 0 1 1 1 1 0 1 0 1 0
Outcome - 0 - - 1 1 - 1 1 0 0 - 0 - 1 -
Table 8.1:
Example of simultaneous output using
IOSET0x2F93
and
IO-
MASK0x4DEA . Only the 9 pins corresponding to bits set in IOMASK are
affected by the command, with “-” denoting no change.
If
IOMASK
is not specified, the value
0xFFFF
is assumed and all HSB