BIOS LPT-, Centronics.
POST BIOS , 378h 278h BIOS DATA AREA 0:0408h, 040Ah, 040, 040. LPT1-LPT4. 0:0478, 0479, 047, 047 , - .
. , , LPT-, BIOS DATA AREA. LPT4 BIOS , .
Initff, 00h, .
BIOS I NT 17h LPT-:
00h AL Centronics. .
01h .
02h .
INT 17h , DX (0 LPT1, 1 LPT2...). SR[7:3] ( 6 3 ) - 0. - .
, PS/2.
1 (Typel parallel port) , PS/2. . , : CR.5=0 , CR.5=1 .
(Type 3 DMA parallel port) PS/2 57, 90, 95. . , , , , Centronics .
IEEE 1284 .
:
-0,5... +5,5 .
14 +2,4 (voh) +0,4 (vol) .
ro, , 50()5 voh-vol. . .
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() 0,05-0,4 /.
IEEE 1284 , - Centronics. . , , ( PC), .
, Centronics (Fast Centronics, Parallel Port FIFO Mode), IEE1284, .
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