pt7a6525 Pericom Technology Inc, pt7a6525 Datasheet - Page 14

• Manufacturer Part Number: pt7a6525
• Description: Pt7a6525/6525l/6526 Hdlc Controller
• Manufacturer: Pericom Technology Inc

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Table 4. Transmit Data Flow
The management of HDLC frames to be transmitted is shown
as follows.
Two different types of frames can be transmitted:
For I frames (command XIF via CMDR register), the address
and control fields are generated autonomously by the device,
PT0017(12/05)
- I frames and
- Transparent frames
T
a r
I
T
T
T
F
T
T
s n
F
a r
p y
p y
p y
p y
p y
a r
a p
m
m
s e
s e
s e
s e
s e
e r
e
e
t n
X
X
F
A
F I
D
O
1
A
A
A
A
A
D
D
D
D
D
D
D
D
D
D
R
R
R
R
R
X
X
F
A
F I
D
O
2
D
D
D
D
D
f i
f i
f i
f i
f i
14
PT7A6525/6525L/6526 HDLC Controller
e f
e f
e f
e f
e f
and the data in the XFIFO enters into the information field of
the frame. This is possible only when the device is in Auto
Mode.
For transparent frames as well (command XTF via CMDR
register), the address and the control fields must be sent to the
XFIFO. This is possible in all operating modes and is also used
in Auto Mode for sending U frames.
e r
e r
e r
e r
e r
A
t n
t n
t n
t n
t n
u
o t
X
C
C
C
C
C
P
P
P
P
P
F
T
T
T
T
T
G
r a
r a
r a
r a
r a
F I
R
R
R
R
R
e
s t
s t
s t
s t
s t
e n
L
L
L
O
L
L
f o
f o
f o
f o
f o
a r
e t
F
F
F
F
F
a r
a r
a r
a r
a r
m
m
m
m
m
s e
s e
s e
s e
s e
X
X
F
F
I I I I I
F I
F I
O
O
Data Sheet
C
C
R
R
C
C
C C
C C
C C
C C
C
G
G
R
R
R
R
R
e
e
e n
e n
C
t a r
t a r
r o
r o
Ver:8