Technical information

Serial Solutions NewBIOS Reference
information:
BX, = Up to 4 bytes information
CX
Meaning._________
Service B2H is used to read or set the type of card that
this serial port occupies, and to read/set the extra information
required to use some cards. NewBIOS itself does not use these
values, but the NewCOM.SYS device driver does. On reading
the card type the value of the type for the port is returned in
BL, and on a write the value in BL is used to set the type. On
reading the card information BX and CX return the required
information, and on a write BX and CX are used to set the
information.
There are three card types currently supported:
Standard IBM- type 0.
This is the usual serial port supplied on the mother board
or addon cards in a PC. This card requires no other information.
Brain Boxes Lynx and Quad cards and compatibles- type 1.
This card allows all eight ports to use the same interrupt
line via special interrupt sharing hardware. The extra information
required is as follows:
BX = Address of card status register. Set by DIP
switches on the card.
CL = Port number, 0 for port 1 on the card, 1 for
port 2 etc.
CH = Interrupt line use by the card.
The interrupt set via (or assumed by) NewBIOS service 0AFH is
ignored by the device driver for Brain Boxes Lynx and Quad
port cards as the interrupt specified here is used instead.
This service is used to set up each port on the card that
will use interrupt sharing (ports on the card can be switched
from the interrupt sharing hardware to a standard interrupt line).
For each call the address of the status register will be the same,
but the port number will be different. NewCOM needs to know
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