
XRT84L38
I
REV. 1.0.1
OCTAL T1/E1/J1 FRAMER
TABLE OF CONTENTS
GENERAL DESCRIPTION................................................................................................ 1
F
IGURE
1. XRT84L38 8-
CHANNEL
DS1 (T1/E1/J1) F
RAMER
............................................................................................................ 1
A
PPLICATIONS
.............................................................................................................................................. 2
F
EATURES
.................................................................................................................................................... 2
ORDERING INFORMATION ................................................................................................................... 3
F
IGURE
2. P
IN
O
UT
OF
THE
XRT84L38 T
OP
V
IEW
(
SEE
PIN
LIST
FOR
NAMES
AND
FUNCTION
)............................................................ 4
TABLE OF CONTENTS.....................................................................................................
I
T
ABLE
1: L
IST
BY
P
IN
N
UMBER
......................................................................................................................................................... 5
PIN DESCRIPTIONS......................................................................................................... 5
T
RANSMIT
S
ERIAL
D
ATA
I
NPUT
...................................................................................................................... 5
O
VERHEAD
I
NTERFACE
............................................................................................................................... 14
R
ECEIVE
S
ERIAL
D
ATA
O
UTPUT
.................................................................................................................. 16
R
ECEIVE
D
ECODER
L
IU
I
NTERFACE
............................................................................................................. 23
T
RANSMIT
E
NCODER
L
IU
I
NTERFACE
........................................................................................................... 23
T
IMING
....................................................................................................................................................... 24
L
IU
C
ONTROL
............................................................................................................................................. 25
JTAG......................................................................................................................................................... 26
M
ICROPROCESSOR
I
NTERFACE
.................................................................................................................... 27
P
OWER
S
UPPLY
P
INS
................................................................................................................................. 30
G
ROUND
P
INS
............................................................................................................................................ 30
N
O
C
ONNECT
P
INS
..................................................................................................................................... 31
E
LECTRICAL
C
HARACTERISTICS
................................................................................................................... 32
A
BSOLUTE
M
AXIMUMS
................................................................................................................................ 32
DC E
LECTRICAL
C
HARACTERISTICS
............................................................................................................. 32
T
ABLE
2: XRT84L38 P
OWER
C
ONSUMPTION
................................................................................................................................. 32
1.0 MICROPROCESSOR INTERFACE BLOCK ......................................................................................... 33
T
ABLE
3: μC/μP S
ELECTION
T
ABLE
................................................................................................................................................ 33
1.1 CHANNEL SELECTION WITHIN THE FRAMER.............................................................................................. 34
T
ABLE
4: C
HANNEL
S
ELECTION
...................................................................................................................................................... 34
F
IGURE
3. S
IMPLIFIED
B
LOCK
D
IAGRAM
OF
THE
M
ICROPROCESSOR
I
NTERFACE
B
LOCK
.................................................................... 35
1.2 THE MICROPROCESSOR INTERFACE BLOCK SIGNAL .............................................................................. 35
T
ABLE
5: XRT84L38 M
ICROPROCESSOR
I
NTERFACE
S
IGNALS
THAT
EXHIBIT
CONSTANT
ROLES
IN
BOTH
THE
I
NTEL
AND
M
OTOROLA
M
ODES
35
T
ABLE
6: I
NTEL
MODE
: M
ICROPROCESSOR
I
NTERFACE
S
IGNALS
...................................................................................................... 36
T
ABLE
7: M
OTOROLA
M
ODE
: M
ICROPROCESSOR
I
NTERFACE
S
IGNALS
............................................................................................. 36
1.3 INTERFACING THE XRT84L38 TO THE LOCAL μC/μP VIA THE MICROPROCESSOR INTERFACE BLOCK 36
1.3.1 INTERFACING THE FRAMER TO THE MICROPROCESSOR OVER AN 8 BIT WIDE BI-DIRECTIONAL DATA BUS 37
1.3.2 DATA ACCESS MODES............................................................................................................................................... 37
1.3.2.1 P
ROGRAMMED
I/O................................................................................................................................................ 37
1.3.2.2 D
ATA
A
CCESS
USING
P
ROGRAMMED
I/O............................................................................................................... 37
F
IGURE
4. I
NTEL
μP I
NTERFACE
SIGNALS
DURING
P
ROGRAMMED
I/O R
EAD
O
PERATION
................................................................... 38
F
IGURE
5. I
NTEL
μP I
NTERFACE
S
IGNALS
DURING
P
ROGRAMMED
I/O W
RITE
O
PERATION
................................................................. 39
F
IGURE
6. M
OTOROLA
μP I
NTERFACE
SIGNALS
DURING
A
P
ROGRAMMED
I/O R
EAD
O
PERATION
....................................................... 40
F
IGURE
7. M
OTOROLA
μP I
NTERFACE
SIGNAL
DURING
P
ROGRAMMED
I/O W
RITE
O
PERATION
........................................................... 41
1.3.2.3 B
URST
M
ODE
I/O
FOR
D
ATA
A
CCESS
................................................................................................................... 41
F
IGURE
8. I
NTEL
μP I
NTERFACE
S
IGNALS
,
DURING
THE
I
NITIAL
R
EAD
O
PERATION
OF
A
B
URST
C
YCLE
.............................................. 43
F
IGURE
9. I
NTEL
μP I
NTERFACE
S
IGNALS
,
DURING
SUBSEQUENT
R
EAD
O
PERATIONS
OF
A
B
URST
I/O C
YCLE
................................... 44
F
IGURE
10. I
NTEL
μP I
NTERFACE
SIGNALS
,
DURING
THE
I
NITIAL
W
RITE
O
PERATION
OF
A
B
URST
C
YCLE
........................................... 46
F
IGURE
11. μP I
NTERFACE
S
IGNALS
,
DURING
SUBSEQUENT
W
RITE
O
PERATIONS
OF
A
B
URST
I/O C
YCLE
......................................... 47
F
IGURE
12. M
OTOROLA
μP I
NTERFACE
S
IGNALS
DURING
THE
I
NITIAL
R
EAD
O
PERATION
OF
A
B
URST
C
YCLE
.................................... 48
F
IGURE
13. M
OTOROLA
μP I
NTERFACE
S
IGNALS
,
DURING
SUBSEQUENT
R
EAD
O
PERATIONS
OF
A
B
URST
I/O C
YCLE
........................ 49
F
IGURE
14. M
OTOROLA
μP I
NTERFACE
SIGNALS
,
DURING
THE
I
NITIAL
W
RITE
O
PERATION
OF
A
B
URST
C
YCLE
.................................. 51
F
IGURE
15. M
OTOROLA
μP I
NTERFACE
S
IGNALS
DURING
SUBSEQUENT
W
RITE
O
PERATIONS
OF
A
B
URST
I/O C
YCLE
........................ 52
1.4 DMA READ/WRITE OPERATIONS................................................................................................................... 52
DMA-0 Write DMA Interface..................................................................................................................................... 53
F
IGURE
16. DMA M
ODE
FOR
THE
XRT84L38
AND
A
M
ICROPROCESSOR
......................................................................................... 53
1.5 MEMORY AND REGISTER MAP...................................................................................................................... 53
1.5.1 MEMORY MAPPED I/O INDIRECT ADDRESSING...................................................................................................... 53