User`s manual

Software Manual • EKF Intelligent I/O Controller Family On CompactPCI
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EKF Elektronik GmbH * Philipp-Reis-Str. 4 * D-59065 HAMM (Germany)
Tel. [phone] * Fax. [phone] * E-Mail [e-mail] * Internet http://www.ekf.de
Purge The Read Buffer: CMDIMR_PURGE_READ
Description:
This command is used to purge the read buffer of a port specified by the
port identifier. The number of bytes in the read buffer is cleared and the
fill pointer reset to the buffer start.
Command Code:
10.
Command Data:
None.
Parameters:
None.
Data:
None.
Command Word:
0x0Y0A 0000
Flags Port ID Command Command Data
E
R
R
R
P
L
C
P
L
U
F
ID
3
ID
2
ID
1
ID
0
C
7
C
6
C
5
C
4
C
3
C
2
C
1
C
0
D
15
D
14
D
13
D
12
D
11
D
10
D
09
D
08
D
07
D
06
D
05
D
04
D
03
D
02
D
01
D0
0
0000YYYY000010100000000000000000
31 28 27 24 23 16 15 8 7 0
Reply:
Flags Port ID Command Command Data
E
R
R
R
P
L
C
P
L
U
F
ID
3
ID
2
ID
1
ID
0
C
7
C
6
C
5
C
4
C
3
C
2
C
1
C
0
D
15
D
14
D
13
D
12
D
11
D
10
D
09
D
08
D
07
D
06
D
05
D
04
D
03
D
02
D
01
D0
0
X110YYYY000010100000000000000000
31 28 27 24 23 16 15 8 7 0
The controller returns with the RPL and CPL flags set.
On error the RPL, CPL and ERR flags are set and an error code is
passed in bits 15:00 of the reply word.
Notes:
This command is useful to synchronize the read ring buffer pointers
maintained by the firmware and the host. Therefore it is necessary for
the host to reset its empty pointer to the read buffer start when executing
this command.