Manual LPCI-COM-8SM
12
Baud Rate Ranges
The jumper labeled CLK X8 provides a means to select baud rates in a higher range. When a
jumper is not placed on the out the CLK X8 position, the baud rate range is up to 115,200 baud.
When it is in the CLK X8 position, the baud rate range is up to 921,600 baud.
Interrupts
Please note that, in WindowsNT, changes must be made to the system registry to support IRQ
sharing. The following is excerpted from "Controlling Multiport Serial I/O Cards" provided by
Microsoft in the MSDN library, documentid:mk:@ivt:nt40res/D15/S55FC.HTM, also available in
the WindowsNT Resource Kit.
The Microsoft serial driver can be used to control many dumb multiport serial cards. Dumb
indicates that the control includes no on-board processor. Each port of a multiport card has a
separate subkey under the HKLM\CurrentControlSet\Services\Serial subkey in the registry. In
each of these subkeys, you must add values for
DosDevices, Interrupt, InterruptStatus,
PortAddress,
and
PortIndex
because these are not detected by the Hardware Recognizer.
(For descriptions and ranges for these values, see Regentry.hlp, the Registry help file on the
WindowsNT Workstation Resource Kit CD.)
For example, if you have an eight-port card configured to use address 0xFC00 with an interrupt
of 05, the values in the Registry are:
Serial2 subkey:
PortAddress = REG_DWORD 0xFC00
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM3
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 1
Indexed = REG_DWORD 0
Serial3 subkey:
PortAddress = REG_DWORD 0xFC08
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM4
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 2
Indexed = REG_DWORD 0
Serial4 subkey:
PortAddress = REG_DWORD 0xFC10
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM5
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 3
Indexed = REG_DWORD 0
Serial5 subkey:
PortAddress = REG_DWORD 0xFC18
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM6
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 4
Indexed = REG_DWORD 0
Serial6 subkey:
PortAddress = REG_DWORD 0xFC20
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM7
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 5
Indexed = REG_DWORD 0
Serial7 subkey:
PortAddress = REG_DWORD 0xFC28
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM8
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 6
Indexed = REG_DWORD 0
Serial8 subkey:
PortAddress = REG_DWORD 0xFC30
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM9
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 7
Indexed = REG_DWORD 0
Serial9 subkey:
PortAddress = REG_DWORD 0xFC38
Interrupt = REG_DWORD 5
DosDevices = REG_SZ COM10
InterruptStatus = REG_DWORD 0xFC40
PortIndex = REG_DWORD 8
Indexed = REG_DWORD 0
Table 3-1:
WindowsNT Registry Values
