The Virtual PORT registers map the most frequently used regular PORT registers
into the bit-accessible I/O space.
Writing to the Virtual PORT
registers has the same effect as writing to the regular registers, but allows for
memory-specific instructions, such as bit-manipulation instructions, which are not valid
for the extended I/O memory space where the regular PORT registers
reside.Table 17-2. Virtual Port Mapping
| Regular PORT Register |
Mapped to Virtual PORT Register |
| PORT.DIR |
VPORT.DIR |
| PORT.OUT |
VPORT.OUT |
| PORT.IN |
VPORT.IN |
| PORT.INTFLAG |
VPORT.INTFLAG |
