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SVR5 and SCO OpenServer 5

RelReqDMA(D4pccard)


RelReqDMA -- describe DMA channel assigned to the PC Card configuration

Syntax

   #include <sys/lcs.h>
   #include <sys/lss.h>
   

Description

The RelReqDMA structure is used to release or request a DMA channel for the configuration of a PC Card in the specified socket.

Structure definition

   unsigned short  	usSocket;
   unsigned short  	usDesiredChannel;
   unsigned short  	usAttributes;
   unsigned char   	ucAssignedChannel;

Structure members

The members are defined as:

usSocket
Logical socket.

usDesiredChannel
Bit-mapped field indicating DMA channel. Bits D0-D15 correspond to DMA channels 0-15. If bit is set to 1, the channel is acceptable to the requesting client. A client can accept any channel if all bits are set to 1.

usAttributes
Bit-mapped field indicating signal to use for DMA request and DMA width.

bits 0-1
Shared mode. Binary value identifying how DMA channel is shared:


1
exclusive (not shared)

1
time-multiplexed shared

2
dynamically shared

3
reserved

bits 2-3
DMA request signal. binary value that identifies the pin on the interface used to signal a DMA request.


0
reserved (do not use)

1
DREQ# uses SPKR#

2
DREQ# uses IOIS16#

3
DREQ# uses INPACK#

bit 4
desired width of a DMA data transfer


0
8 bits

1
16 bits

bits 5-7
resesrved (reset to zero)

ucAssignedChannel
Binary value indicating assigned DMA channel.

Usage

Hardware applicability

All

Version applicability

pccard: 1, 2, 3

References

ReleaseDMA(D3pccard), RequestDMA(D3pccard)
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005