Technical information

Serial Solutions Using NewBIOS
NewBIOS.
Service B1H, Get/Set Software Handshake.
This service exists to support NewCOM, which can use
software handshakes. A software handshake uses special
characters, conventionally called XON and XOFF, to
control the flow of data. This is to be compared with a
hardware handshake, where control lines fulfil the same
purpose. Subservices 0 and 1 allow software handshaking
to be turned on and off, and subservices 2 and 3 allow the
actual characters to be used as XON and XOFF to be
changed.
Service B2H, Get/Set Card Type.
This service exists to support NewCOM, which can use
non-standard serial cards. The inherent limitation of the
serial ports on a standard IBM PC or clone is the number
of ports that can use buffered i/o. Many cards are therefore
manufactured which circumvent this limitation. These
require special treatment, and this service tells the device
driver that the port specified is on a special card, and
supplies any relevant additional information.
Service B3H, Get/Control Buffers.
This service exists to support NewCOM, which can use
buffered i/o for more convenient and efficient serial
input/output. Subservices 0 and 1 read the status of the
buffers associated with a port. Subservices 2 and 3 flush
the buffers. Subservices 4,5,6 and 7 can disable/enable the
buffers for a port.
The next chapter lists comprehensive details of all
NewBIOS services. The following sections of this chapter cover
the use of the services, and will introduce details of particular
services only as necessary. This is not intended as a
comprehensive tutorial in serial communications, rather it will
demonstrate how to use NewBIOS.
Installing NewBIOS.__________________
There are two ways to add NewBIOS to your system. For
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