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INP and INPW

Inputs a Byte or Word from an I/O Port.
 
INP(port)
INPW(port)
 
Usage:
PRINT IVAL$(INPW(&H300),16)
X=INP(Base+3)
 
Example:          INP.BAS  INPW.BAS
 
Description:
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.
 
See Also: