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