B&B Electronics Parallel Port Input/Output Converter PPIO Benutzerhandbuch

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PPIO2899 Manual 

used to read the status of the port. The PPIO does not need to use 
this port as an input port. 
 
 

Again, referring to Table 1, if you input the data on port 

0379H, then whatever TTL level pins 15, 13, 12, 10, and 11 are will 
show up as bits 3 through 7. The state of bits 0, 1, and 2 will be 
unknown since they are not hooked to anything, but they probably 
will be HIGH (ONE). Note that the data on pin 11 will be inverted, if 
pin 11 is LOW you will get a HIGH on bit 7. The pins with the “bars” 
over them are all inverted. This is done by the hardware in the 
parallel port over which we have no control. A way to read these pins 
using GWBASIC is: A1=INP(&H379). A1 will then have the results of 
the input from port address 0379H. Bit 3 of A1 will have the status of 
pin 15, bit 4 the status of pin 13, etc. 
 
 

Note that on the third address (037AH) the pins can be 

either inputs or outputs. If you use the GWBASIC command  OUT 
&H37A,&H01 (00000001 BINARY) then pin 1 will be LOW (because 
it is inverted), pins 14 and 17 will be HIGH (they also are inverted), 
and pin 16 will be LOW (it is not inverted).