lpt 893 B

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  1. .TH LPT 3
  2. .SH NAME
  3. lpt \- parallel port interface for PC's
  4. .SH SYNOPSIS
  5. .nf
  6. .B bind -a #L[123] /dev
  7. .B /dev/lpt[123]data
  8. .B /dev/lpt[123]dlr
  9. .B /dev/lpt[123]pcr
  10. .B /dev/lpt[123]psr
  11. .fi
  12. .SH DESCRIPTION
  13. The
  14. .I lpt
  15. driver provides an interface to the parallel
  16. interface normally used for printers.
  17. The specifiers
  18. .BR 1 ,
  19. .BR 2 ,
  20. and
  21. .BR 3
  22. correspond to
  23. the parallel interfaces at PC ports 0x3bc, 0x378, and 0x278
  24. respectively.
  25. .PP
  26. .B Lpt?data
  27. is write only.
  28. Writing to it sends data to the interface.
  29. This file is sufficient for communicating with most printers.
  30. .PP
  31. .BR Lpt?dlr ,
  32. .BR lpt?pcr ,
  33. and
  34. .B lpt?psr
  35. are used for fine control of the parallel port.
  36. Reading or writing these files corresponds to
  37. reading and writing the data latch register,
  38. printer control register, and printer status
  39. register.
  40. These are used by programs to drive special devices.
  41. .SH SOURCE
  42. .B /sys/src/9/pc/devlpt.c