HWML 4-Axis Stepper Motor Controller LPT Emulation

  DB25F  
CONTROL bit 0 (inverted)   1 o  
o 14   CONTROL bit 1 (inverted)
DATA bit 0   2 o
o 15   STATUS bit 3
DATA bit 1   3 o
o 16   CONTROL bit 2
DATA bit 2   4 o
o 17   CONTROL bit 3 (inverted)
DATA bit 3   5 o
o 18   GND
DATA bit 4   6 o
o 19   GND
DATA bit 5   7 o
o 20   GND
DATA bit 6   8 o
o 21   GND
DATA bit 7   9 o
o 22   GND
STATUS bit 6   10 o
o 23   GND
STATUS bit 7 (inverted)   11 o
o 24   GND
STATUS bit 5   12 o
o 25   GND
STATUS bit 4   13 o
 


Byte Bit Query (from Host to Controller) Answer (from Controller to Host)
Header 7 Always 1 Always 1
6 1 - CONTROL byte to set supplied 1 - CONTROL byte info supplied
5 1 - STATUS byte to set supplied 1 - STATUS byte info supplied
4 1 - DATA byte to set supplied 1 - DATA byte info supplied
3 Always 1 Always 0
2 1 - CONTROL byte info requested Always 0
1 1 - STATUS byte info requested Always 0
0 1 - DATA byte info requested Always 0
Resource 7-0 Optional DATA byte if Header's bit 4 is 1
Resource 7-0 Optional STATUS byte if Header's bit 5 is 1
Resource 7-0 Optional CONTROL byte if Header's bit 6 is 1


(C) Aryeh Eiderman  < leib @ hwml . com >