I don't know that there's a direct spec, but if you look in the AC (Timing) Characteristics section
you'll find a 'CLKO AND I/O TIMING REQUIREMENTS' table. Parameter TosH2ioV should give you a ballpark
idea as to the speed of the IO pins. The transitions into and out of tristate would probably be longer than this.
Since you have a group of port pins over several ports the time required to change the direction will
likely overshadow those numbers. Something like
Code:
TRISA = $55
TRISB = $AA
TRISC = $CC
will take a min of 6 instructions (2 per TRIS setting), so on a PIC18 that's 6 x 4 = 24 Tosc periods.
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