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PEB 20321
PEF 20321
Host Memory Organization
Data Sheet
313
2001-02-14
MUNICH32X then branches to the Tx descriptor determined by FTDA even
though the HOLD bit of the current Tx descriptor may still be
‘
1
’
.
Host initiated Interrupt; if the HI bit is set, the MUNICH32X generates an
interrupt with set HI bit after transferring all data bytes.
This byte number (together with NO13) defines the number of bytes stored in
the data section to be transmitted. A Tx descriptor and the corresponding data
section must contain at least either one data byte or a frame end indication.
Otherwise an interrupt with set ERR bit is generated.
This bit indicates that in the corresponding data section the E-, S- and X-bits
of the following V.110/X.30 frame are stored. The MUNICH32X reads these
bits and inserts them into the next possible V.110/X.30 frame. The data
section may contain only the two bytes specified in the next figure (in little
endian format).
The first Tx descriptor after a transmit initialization channel command
must
have the V.110 bit set if it revives the channel from a transmit off condition or
after a reset.
Not supported by LBI.
This bit field is the MSB of NO.
HI:
NO:
V.110:
NO13:
Tx Descriptor Data Section in V.110 Mode
(Not supported by LBI.)
CSM:
CRC Select per Message: This bit is only valid in HDLC mode with CS = 0 and
only in conjunction with the FE bit set. If set, it means that no FCS is
generated automatically for the frame finished in this transmit descriptor.
FNUM denotes the number of interframe time-fill characters between
2 HDLC or TMB frames. For X.30/V.110 these bits have to be programmed
to
‘
0
’
.
FNUM = 0 means that after the current frame only 1 character (7E
H
for HDLC
and 00
H
for TMB, 000
H
for TMR, TFLAG, TFLAG for TMA, FA =
‘
1
’
; FF
H
for
TMA, FA =
‘
0
’
) is sent before the following frame (shared flags).
FNUM = 1 means that after the current frame 2 characters (7E
H
7E
H
for
HDLC and 00
H
00
H
for TMB and TMR, TFLAG, TFLAG for TMA, FA =
‘
1
’
;
FNUM:
31
E7
30
E6
29
E5
28
E4
27
E3
26
E2
25
E1
24
SB
23
SA
22
X
21
0
20
0
19
0
18
0
17
0
16
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0000
H