I try to use a PIC16C84 and I get MICROCHIP documentation. There is something
strange:

  PortB can generate INTERRUPT when there is change on RB.4..7, the
documentation said: these pins are sampled on the Q1 cycle of read.
The new input is compared with old latched value in every instruction cycle.

HOW IT IS possible an interrupt occurs if portB is latched only on a READ
instruction ?
Does this means that it's neccessary to read PORTB every time to generate
an interrupt ?
MICROCHIP Doc. said: PortB can generate instruction in SLEEP mode, HOW it
is possible if portB is latched only on a read ?

Is it a mistake of the MICROCHIP doc. ?

Someone can help me please,

        Philippe <sonyede@iway.fr>