Technical information

Serial Solutions NewBIOS Reference
Service 4H, Extended Initialise.___________________________
Compatibility._____________
This service was first used in the ROM BIOS of IBM PS/2
machines and is supported by most modern PCs. The NewBIOS
version is fully compatible with the version documented in the
PS/2 BIOS technical reference, but allows a wider range of baud
rates.
Parameters.___________
AH = 04H Denotes service 4H
AL is Break control, where
= 0 no break
= 1 break
BH is Parity, where
= 00H None
= 01H Odd
= 02H Even
= 03H Mark (Stick parity odd)
= 04H Space (Stick parity even)
BL is Stop bits, where
= 00H One
= 01H Two (One and a half for 5-bit word
length)
CH is Word length, where
= 00H 5 bits
= 01H 6 bits
= 02H 7 bits
= 03H 8 bits
CL is Baud rate, where
= 00H 110 Baud
= 01H 150 Baud
= 02H 300 Baud
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