Interrupts, Serial2 Subkey | Access PCI-COM422/4 specs

PCI-COM422/4 Manual

Interrupts

Please note that, in Windows NT, 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 text enclosed in brackets ("[ ]") denotes a comment by ACCES.

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 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 a four-port PCI-COM422/4 card configured to use address 0xFFF0 with an interrupt of 0xFFF8, the values in the Registry are: [assuming that every port is configured to use the same IRQ and that the addresses are configured to be consecutive and contiguous]

Serial2 Subkey:

PortAddress = REG_DWORD 0xFFF0 Interrupt = REG_WORD 5 DosDevices = REG_SZ COM3 InterruptStatus = REG_DWORD 0xFFF8 PortIndex = REG_DWORD 1

Serial3 Subkey:

PortAddress = REG_DWORD 0xFFE0 Interrupt = REG_DWORD 5 DosDevices = REG_SZ COM4 InterruptStatus = REG_DWORD 0xFFF8 PortIndex = REG_DWORD 2

Serial4 Subkey:

PortAddress = REG_DWORD 0xFF90 Interrupt = REG_DWORD 5 DosDevices = REG_SZ COM5 InterruptStatus = REG_DWORD 0xFFF8 PortIndex - REG_DWORD 3

Serial5 Subkey:

PortAddress = REG_DWORD 0xFF80 Interrupt = REG_DWORD 5

Dos Devices = REG_SZ COM6 InterruptStatus = REG_DWORD 0xFFF8 PortIndex = REG_DWORD 4

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Manual MPCICOM422-4.E1b