The INP statement inputs a byte from the specified I/O port. The value returned will be an integer in the range 0 to 255. It is equivalent to READIO(8080,Port).
The INPW statement inputs an INTEGER from the specified I/O port. It is equivalent to READIO(-8080,Port). These statements are useful for doing I/O with devices, data acquisition boards, etc. for which there is no available device driver.
Some operating systems protect I/O ports; applications are not allowed to read or write them. Under such operating systems, these functions are not allowed. Windows NT is such an operating system.
Back-Porting
to HP BASIC:
INP and INPW are unique HTBasic functions not available in HP BASIC. They should not be used in programs that must be ported back to HP BASIC.