Brainboxes 1 Port Rs232 Card, Руководство пользователя

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1 Port RS232 Card Chapter 4
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/I IRQ, range
specifies card interrupt and COM port range. The COM port range
specifies the
COM port(s). Range may be a single port OR a range of ports.
/B number buffer
is used to set the number of pairs of buffers to be allocated to ports and is a
decimal number in the range 1-maxport.
/S buffer
Set size of all buffers in bytes, buffer is rounded to the nearest power of 2 and
must be a decimal number in the range 32 to 32768. For any serial port opened
two buffers of size buffer are allocated, one for input and the other for output.
/H hardware handshake
selects which hardware handshake type to use on the specified ports. This is used
in the following manner: /H range, hs where range specifies the COM port or
ports and hs selects handshake type. Handshake types available are:
Type 0 RS232 DTR/CTS - The PC only transmits when CTS is input true.
When the PC is able to receive its sets DTR output true. The DSR and DCD
inputs are ignored. The RTS output line is set true just in case the external serial
device needs a true signal.
Type 4, 3 Wire Handshake - Really no handshake at all since the PC transmits
irrespective of the handshake lines. The 3 wires are TxD, RxD and Ground, no
other lines are required. Thus the CTS, DSR and DCD inputs are ignored. The
RTS and DTR output lines are set true just in case the external serial device
needs a true signal.
Note: If hardware handshaking is not specified in the NEWCOM.SYS
parameters, type 4, 3 Wire Handshake is selected automatically.
Configuring And Installing NEWCOM.SYS
To load the Serial Solutions for DOS device driver an entry needs to be added to
the CONFIG.SYS file. Any simple text editor, EDIT for example, can edit the
CONFIG.SYS file for example. The installation procedure given below is for a
PCI Dual RS232 as COM 5 - COM6.
The parameter required by the NEWCOM.SYS driver are those returned by the
BBCARDS.EXE application earlier. A brief explanation for the parameters
required by NEWCOM.SYS follows:
Port Address.
/A5,0140
COM port 5 defined, with an i/o address range that begins at 0140h.
IRQ, Range
.
/I 11,5
11 is the IRQ and since the COM port range is COM5 range is entered as 5.
Number Buffer.
/B5
Five buffers are defined, though only two ports are in use - this is because
buffers in DOS are assigned in a sequential order from COM1. Since the PCI 1
Port RS232 has been assigned a COM port value of 5 , all preceding COM ports,
must have buffers assigned to them also.