DALLAS DS21FF44

DS21FT44/DS21FF44
4x3 Twelve Channel E1 Framer
4x4 Sixteen Channel E1 Framer
www.dalsemi.com
FEATURES
·
Sixteen (16) or twelve (12) completely
independent E1 Framers in one small 27mm
x 27mm Package
·
DS21FF44 and DS21FT44 are pin
compatible with DS21FF42 and DS21FT42,
respectively to allow the same footprint to
support T1 and E1 applications
·
Each Multi-Chip Module (MCM) contains
either four (FF) or three (FT) DS21Q44 die
·
300–pin MCM BGA 1.27 mm pitch package
(27mm X 27mm)
·
Each quad framer can be concatenated into a
single 8.192MHz Backplane Data Stream
·
Low power 3.3V CMOS with 5V tolerant
input & outputs
·
IEEE 1149.1 JTAG-Boundary Scan
Architecture
1. MULTI-CHIP MODULE (MCM) DESCRIPTION
The Four x Four and Four x Three MCMs offer a high density packaging arrangement for the DS21Q44
E1 Enhanced Quad Framer. Either three (DS21FT44) or four (DS21FF44) silicon die of these devices is
packaged in a Multi-Chip Module (MCM) with the electrical connections as shown in Figure 1-1.
All of the functions available on the DS21Q44 are also available in the MCM packaged version.
However, in order to minimize package size, some signals have been deleted or combined. These
differences are detailed in Table 1-1. In the Four x Three (FT) version, the fourth quad framer is not
populated and hence all of the signals to and from this fourth framer are absent and should be treated as
No Connects (NC). Table 2-1 lists all of the signals on the MCM and it also lists the absent signals for
the Four x Three.
The availability of both a twelve and a sixteen-channel version allow the maximum framer density with
the lowest cost.
1 of 110
120601
DS21FT44/DS21FF44
Changes from Normal DS21Q44 Configuration Table 1-1
1. TSYSCLK and RSYSCLK are tied together.
2. The following signals are not available:
RFSYNC / RLCLK / RLINK / RCHCLK / RMSYNC / RLOS/LOTC / TCHBLK /
TLCLK / TLINK / TCHCLK
DS21FT44 / DS21FF44 Schematic Figure 1-1
DS21Q44 # 1
DVSS
DVSS
FMS
TLINK0/1/2/3
TEST
MUX
BTS
2
FS0/FS1
WR*
RD*
A0 to A7
8
8
Signals Not Connected &
Left Open Circuited Include:
RLOS/LOTC
RLINK
RLCLK
RCHCLK
RMSYNC
RFSYNC
TLCLK
TCHCLK
TCHBLK
RCLK1/2/3/4
RPOS1/2/3/4
RNEG1/2/3/4
RSER1/2/3/4
RSIG1/2/3/4
RSYNC1/2/3/4
RCHBLK1/2/3/4
TSYSCLK1/2/3/4
TCLK1/2/3/4
INT*
JTRST
TPOS1/2/3/4
TNEG1/2/3/4
JTMS
JTCLK
TSER1/2/3/4
TSIG1/2/3/4
JTDI
JTDO
TSSYNC1/2/3/4
TSYNC1/2/3/4
DS21Q44 # 2
DVSS
DVSS
CLKSI
FMS
TLINK0/1/2/3
TEST
MUX
BTS
RD*
A0 to A7
CLKSI
8MCLK
RSYSCLK1/2/3/4
D0 to D7
CS*
FS0/FS1
WR*
DVDD
Signals Not Connected &
Left Open Circuited Include:
RLOS/LOTC
RLINK
RLCLK
RCHCLK
RMSYNC
RFSYNC
TLCLK
TCHCLK
TCHBLK
8MCLK
D0 to D7
CS*
DVDD
RCLK5/6/7/8
RPOS5/6/7/8
RNEG5/6/7/8
RSER5/6/7/8
RSIG5/6/7/8
RSYNC5/6/7/8
RCHBLK5/6/7/8
RSYSCLK5/6/7/8
TSYSCLK5/6/7/8
TCLK5/6/7/8
INT*
JTRST
TPOS5/6/7/8
TNEG5/6/7/8
JTMS
JTCLK
TSER5/6/7/8
TSIG5/6/7/8
JTDI
JTDO
TSSYNC5/6/7/8
TSYNC5/6/7/8
See Connecting Page
2 of 110
DS21FT44/DS21FF44
DS21FF44 / DS21FT44 Schematic Figure 1-1 (continued)
See Connecting Page
DVSS
DVSS
CLKSI
FMS
TLINK0/1/2/3
TEST
MUX
BTS
FS0/FS1
WR*
RD*
A0 to A7
D0 to D7
DVDD
DS21Q44 # 3
Signals Not Connected &
Left Open Circuited Include:
RLOS/LOTC
RLINK
RCLK9/10/11/12
RLCLK
RPOS9/10/11/12
RCHCLK
RNEG9/10/11/12
RMSYNC
RFSYNC
RSER9/10/11/12
TLCLK
RSIG9/10/11/12
TCHCLK
RSYNC9/10/11/12
TCHBLK
8MCLK
RCHBLK9/10/11/12
RSYSCLK9/10/11/12
TSYSCLK9/10/11/12
CS*
INT*
TCLK9/10/11/12
TPOS9/10/11/12
JTRST
JTMS
jtdot
TNEG9/10/11/12
TSER9/10/11/12
JTCLK
JTDI
TSIG9/10/11/12
TSSYNC9/10/11/12
JTDO
TSYNC9/10/11/12
DVSS
DVSS
CLKSI
FMS
TLINK0/1/2/3
TEST
MUX
BTS
FS0/FS1
WR*
RD*
A0 to A7
D0 to D7
CS*
INT*
JTRST
DVDD
DS21Q44 # 4
Signals Not Connected &
Left Open Circuited Include:
RLOS/LOTC
RLINK
RCLK13/14/15/16
RLCLK
RPOS13/14/15/16
RCHCLK
RNEG13/14/15/16
RMSYNC
RFSYNC
RSER13/14/15/16
TLCLK
RSIG13/14/15/16
TCHCLK
RSYNC13/14/15/16
TCHBLK
8MCLK
RCHBLK13/14/15/16
RSYSCLK13/14/15/16
TSYSCLK13/14/15/16
TCLK13/14/15/16
TPOS13/14/15/16
TNEG13/14/15/16
JTMS
JTCLK
jtdof
JTDI
JTDO
TSER13/14/15/16
TSIG13/14/15/16
TSSYNC13/14/15/16
TSYNC13/14/15/16
The Fourth Quad Framer
is Not Populated
on the 12 Channel
DS21FT44
3 of 110
DS21FT44/DS21FF44
TABLE OF CONTENTS
1. MULTI-CHIP MODULE (MCM) DESCRIPTION.........................................................................1
2. MCM LEAD DESCRIPTION ............................................................................................................7
3. DS21FF44 (Four x Four) PCB LAND PATTERNS .......................................................................15
4. DS21FT44 (Four x Three) PCB Land Pattern................................................................................16
5. DS21Q42 DIE DESCRIPTION ........................................................................................................17
6. DS21Q44 INTRODUCTION ............................................................................................................18
7. DS21Q44 PIN FUNCTION DESCRIPTION ..................................................................................21
8. DS21Q44 REGISTER MAP .............................................................................................................27
9. PARALLEL PORT ...........................................................................................................................32
10. CONTROL, ID AND TEST REGISTERS......................................................................................32
11. STATUS AND INFORMATION REGISTERS .............................................................................41
12. ERROR COUNT REGISTERS........................................................................................................47
13. DS0 MONITORING FUNCTION ...................................................................................................49
14. SIGNALING OPERATION .............................................................................................................52
14.1 PROCESSOR BASED SIGNALING ............................................................................................................52
14.2 HARDWARE BASED SIGNALING ..............................................................................................................55
15. PER–CHANNEL CODE GENERATION AND LOOPBACK.....................................................56
15.1 TRANSMIT SIDE CODE GENERATION.....................................................................................................56
15.1.1
Simple Idle Code Insertion And Per–Channel Loopback....................................................................56
15.1.2
Per–Channel Code Insertion...............................................................................................................57
15.2 RECEIVE SIDE CODE GENERATION .......................................................................................................58
16. CLOCK BLOCKING REGISTERS................................................................................................59
17. ELASTIC STORES OPERATION..................................................................................................60
17.1 RECEIVE SIDE............................................................................................................................................61
17.2 TRANSMIT SIDE .........................................................................................................................................61
18. ADDITIONAL (Sa) AND INTERNATIONAL (Si) BIT OPERATION ......................................61
18.1 HARDWARE SCHEME ...............................................................................................................................61
18.2 INTERNAL REGISTER SCHEME BASED ON DOUBLE–FRAME.............................................................62
18.3 INTERNAL REGISTER SCHEME BASED ON CRC4 MULTIFRAME ........................................................63
19. HDLC CONTROLLER FOR THE SA BITS OR DS0 ..................................................................65
19.1 GENERAL OVERVIEW ...............................................................................................................................65
19.2 HDLC STATUS REGISTERS ......................................................................................................................66
19.3 BASIC OPERATION DETAILS....................................................................................................................67
19.4 HDLC REGISTER DESCRIPTION ..............................................................................................................68
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DS21FT44/DS21FF44
20. INTERLEAVED PCM BUS OPERATION....................................................................................74
21. JTAG-BOUNDARY SCAN ARCHITECTURE AND TEST ACCESS PORT...........................77
21.1 DESCRIPTION ............................................................................................................................................77
21.2 TAP CONTROLLER STATE MACHINE ......................................................................................................78
21.3 INSTRUCTION REGISTER AND INSTRUCTIONS ....................................................................................80
21.4 TEST REGISTERS ......................................................................................................................................82
22. TIMING DIAGRAMS.......................................................................................................................86
23. OPERATING PARAMETERS ........................................................................................................96
24. MCM PACKAGE DIMENSIONS .................................................................................................109
5 of 110
DS21FT44/DS21FF44
DOCUMENT REVISION HISTORY
REVISION
8-7-98
12-29-98
10-18-99
02-03-00
NOTES
Initial Release
TEST and MUX leads were added at previous No Connect (NC) leads.
DS21Q42 die specifications appended to data sheet.
Conversion from Interleaf to Microsoft Word
6 of 110
DS21FT44/DS21FF44
2. MCM LEAD DESCRIPTION
Lead Description Sorted by Symbol Table 2-1
Lead
B7
G20
H20
G19
H19
G18
H18
G17
H17
W15
B6
T8
Y4
Y15
E19
L20
M20
L19
M19
L18
M18
L17
M17
C7
E4
D2
K3
U7
P2
V19
T12
L16
D17
Symbol
8MCLK
A0
A1
A2
A3
A4
A5
A6
A7
BTS
CLKSI
CS1*
CS2*
CS3*
CS4*/NC
D0
D1
D2
D3
D4
D5
D6
D7
DVDD1
DVDD1
DVDD1
DVDD2
DVDD2
DVDD2
DVDD3
DVDD3
DVDD3
DVDD4/NC
I/O
O
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
–
–
–
–
–
–
–
–
–
–
F16
DVDD4/NC
–
B11
DVDD4/NC
–
E9
A6
D5
U3
K4
DVSS1
DVSS1
DVSS1
DVSS2
DVSS2
–
–
–
–
–
Description
8.192 MHz Clock Based on CLKSI.
Address Bus Bit 0 (lsb).
Address Bus Bit 1.
Address Bus Bit 2.
Address Bus Bit 3.
Address Bus Bit 4.
Address Bus Bit 5.
Address Bus Bit 6.
Address Bus Bit 7 (msb).
Bus Timing Select. 0 = Intel / 1 = Motorola.
Reference clock for the 8.192MHz clock synthesizer.
Chip Select for Quad Framer 1.
Chip Select for Quad Framer 2.
Chip Select for Quad Framer 3.
Chip Select for Quad Framer 4. NC on Four x Three.
Data Bus Bit 0 (lsb).
Data Bus Bit 1.
Data Bus Bit 2.
Data Bus Bit 3.
Data Bus Bit 4.
Data Bus Bit 5.
Data Bus Bit 6.
Data Bus Bit 7 (msb).
Digital Positive Supply for Framer 1.
Digital Positive Supply for Framer 1.
Digital Positive Supply for Framer 1.
Digital Positive Supply for Framer 2.
Digital Positive Supply for Framer 2.
Digital Positive Supply for Framer 2.
Digital Positive Supply for Framer 3.
Digital Positive Supply for Framer 3.
Digital Positive Supply for Framer 3.
Digital Positive Supply for Framer 4. NC on Four x
Three.
Digital Positive Supply for Framer 4. NC on Four x
Three.
Digital Positive Supply for Framer 4. NC on Four x
Three.
Digital Signal Ground for Framer 1.
Digital Signal Ground for Framer 1.
Digital Signal Ground for Framer 1.
Digital Signal Ground for Framer 2.
Digital Signal Ground for Framer 2.
7 of 110
DS21FT44/DS21FF44
Lead
U8
U4
R16
Y20
J20
A11
D19
Y14
W14
G16
V14
E10
A19
Symbol
DVSS2
DVSS3
DVSS3
DVSS3
DVSS4/NC
DVSS4/NC
DVSS4/NC
FS0
FS1
INT*
JTCLK
JTDI
JTDOF/NC
I/O
–
–
–
–
–
–
–
I
I
O
I
I
O
T17
H16
K17
A13
JTDOT
JTMS
JTRST*
TEST
O
I
I
I
P17
MUX
I
C2
G3
E6
A8
N1
Y1
U6
N5
Y8
W12
V17
U17
D16
K20
B18
B16
A2
K1
D10
B9
M3
V1
W6
J3
T9
RCHBLK1
RCHBLK2
RCHBLK3
RCHBLK4
RCHBLK5
RCHBLK6
RCHBLK7
RCHBLK8
RCHBLK9
RCHBLK10
RCHBLK11
RCHBLK12
RCHBLK13/NC
RCHBLK14/NC
RCHBLK15/NC
RCHBLK16/NC
RCLK1
RCLK2
RCLK3
RCLK4
RCLK5
RCLK6
RCLK7
RCLK8
RCLK9
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
I
I
I
I
I
I
I
I
I
Description
Digital Signal Ground for Framer 2.
Digital Signal Ground for Framer 3.
Digital Signal Ground for Framer 3.
Digital Signal Ground for Framer 3.
Digital Signal Ground for Framer 4. NC on Four x Three.
Digital Signal Ground for Framer 4. NC on Four x Three.
Digital Signal Ground for Framer 4. NC on Four x Three.
Framer Select 0 for the Parallel Control Port.
Framer Select 1 for the Parallel Control Port.
Interrupt for all four Quad Framers.
JTAG Clock.
JTAG Data Input.
JTAG Data Output for Four x Four Version. NC on Four
x Three.
JTAG Data Output for Four x Three Version.
JTAG Test Mode Select.
JTAG Reset.
Tri-State. 0 = do not tri-state / 1 = tri-state all outputs &
I/O signals
Bus Operation Select. 0 = non-multiplexed bus / 1 =
multiplexed bus
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock.
Receive Channel Blocking Clock. NC on Four x Three.
Receive Channel Blocking Clock. NC on Four x Three.
Receive Channel Blocking Clock. NC on Four x Three.
Receive Channel Blocking Clock. NC on Four x Three.
Receive Clock for Framer 1
Receive Clock for Framer 2.
Receive Clock for Framer 3.
Receive Clock for Framer 4.
Receive Clock for Framer 5.
Receive Clock for Framer 6.
Receive Clock for Framer 7.
Receive Clock for Framer 8.
Receive Clock for Framer 9.
8 of 110
DS21FT44/DS21FF44
Lead
W10
Y18
N17
D14
P20
C18
C12
E18
B2
H2
D9
A9
M2
V3
V7
P3
U9
W11
W17
T20
E14
Symbol
RCLK10
RCLK11
RCLK12
RCLK13/NC
RCLK14/NC
RCLK15/NC
RCLK16/NC
RD*
RNEG1
RNEG2
RNEG3
RNEG4
RNEG5
RNEG6
RNEG7
RNEG8
RNEG9
RNEG10
RNEG11
RNEG12
RNEG13/NC
I/O
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
N20
RNEG14/NC
I
C20
RNEG15/NC
I
B13
RNEG16/NC
I
A1
H1
H4
C9
M1
W2
V5
P4
T10
V11
Y19
R19
D15
RPOS1
RPOS2
RPOS3
RPOS4
RPOS5
RPOS6
RPOS7
RPOS8
RPOS9
RPOS10
RPOS11
RPOS12
RPOS13/NC
I
I
I
I
I
I
I
I
I
I
I
I
I
J18
RPOS14/NC
I
A20
RPOS15/NC
I
Description
Receive Clock for Framer 10.
Receive Clock for Framer 11.
Receive Clock for Framer 12.
Receive Clock for Framer 13. NC on Four x Three.
Receive Clock for Framer 14. NC on Four x Three.
Receive Clock for Framer 15. NC on Four x Three.
Receive Clock for Framer 16. NC on Four x Three.
Read Input.
Receive Negative Data for Framer 1.
Receive Negative Data for Framer 2.
Receive Negative Data for Framer 3.
Receive Negative Data for Framer 4.
Receive Negative Data for Framer 5.
Receive Negative Data for Framer 6.
Receive Negative Data for Framer 7.
Receive Negative Data for Framer 8.
Receive Negative Data for Framer 9.
Receive Negative Data for Framer 10.
Receive Negative Data for Framer 11.
Receive Negative Data for Framer 12.
Receive Negative Data for Framer 13. NC on Four x
Three.
Receive Negative Data for Framer 14. NC on Four x
Three.
Receive Negative Data for Framer 15. NC on Four x
Three.
Receive Negative Data for Framer 16. NC on Four x
Three.
Receive Positive Data for Framer 1.
Receive Positive Data for Framer 2.
Receive Positive Data for Framer 3.
Receive Positive Data for Framer 4.
Receive Positive Data for Framer 5.
Receive Positive Data for Framer 6.
Receive Positive Data for Framer 7.
Receive Positive Data for Framer 8.
Receive Positive Data for Framer 9.
Receive Positive Data for Framer 10.
Receive Positive Data for Framer 11.
Receive Positive Data for Framer 12.
Receive Positive Data for Framer 13. NC on Four x
Three.
Receive Positive Data for Framer 14. NC on Four x
Three.
Receive Positive Data for Framer 15. NC on Four x
Three.
9 of 110
DS21FT44/DS21FF44
Lead
A14
Symbol
RPOS16/NC
I/O
I
C1
H3
C6
C8
P1
W4
T7
N4
U11
Y12
V16
T16
E16
F20
RSER1
RSER2
RSER3
RSER4
RSER5
RSER6
RSER7
RSER8
RSER9
RSER10
RSER11
RSER12
RSER13/NC
RSER14/NC
O
O
O
O
O
O
O
O
O
O
O
O
O
O
C16
RSER15/NC
O
A12
RSER16/NC
O
D3
G2
D4
D8
N2
V4
V6
K5
U10
Y11
W19
U20
E15
RSIG1
RSIG2
RSIG3
RSIG4
RSIG5
RSIG6
RSIG7
RSIG8
RSIG9
RSIG10
RSIG11
RSIG12
RSIG13/NC
O
O
O
O
O
O
O
O
O
O
O
O
O
K19
RSIG14/NC
O
C17
RSIG15/NC
O
A15
RSIG16/NC
O
B1
G1
D6
A7
N3
Y2
RSYNC1
RSYNC2
RSYNC3
RSYNC4
RSYNC5
RSYNC6
I/O
I/O
I/O
I/O
I/O
I/O
Description
Receive Positive Data for Framer 16. NC on Four x
Three.
Receive Serial Data from Framer 1.
Receive Serial Data from Framer 2.
Receive Serial Data from Framer 3.
Receive Serial Data from Framer 4.
Receive Serial Data from Framer 5.
Receive Serial Data from Framer 6.
Receive Serial Data from Framer 7.
Receive Serial Data from Framer 8.
Receive Serial Data from Framer 9.
Receive Serial Data from Framer 10.
Receive Serial Data from Framer 11.
Receive Serial Data from Framer 12.
Receive Serial Data from Framer 13. NC on Four x Three.
Receive Serial Data from Framer 14. NC on Four x
Three.
Receive Serial Data from Framer 15. NC on Four x
Three.
Receive Serial Data from Framer 16. NC on Four x
Three.
Receive Signaling Output from Framer 1.
Receive Signaling Output from Framer 2.
Receive Signaling Output from Framer 3.
Receive Signaling Output from Framer 4.
Receive Signaling Output from Framer 5.
Receive Signaling Output from Framer 6.
Receive Signaling Output from Framer 7.
Receive Signaling Output from Framer 8.
Receive Signaling Output from Framer 9.
Receive Signaling Output from Framer 10.
Receive Signaling Output from Framer 11.
Receive Signaling Output from Framer 12.
Receive Signaling Output from Framer 13. NC on Four x
Three.
Receive Signaling Output from Framer 14. NC on Four x
Three.
Receive Signaling Output from Framer 15. NC on Four x
Three.
Receive Signaling Output from Framer 16. NC on Four x
Three.
Receive Frame/Multiframe Sync for Framer 1.
Receive Frame/Multiframe Sync for Framer 2.
Receive Frame/Multiframe Sync for Framer 3.
Receive Frame/Multiframe Sync for Framer 4.
Receive Frame/Multiframe Sync for Framer 5.
Receive Frame/Multiframe Sync for Framer 6.
10 of 110
DS21FT44/DS21FF44
Lead
U5
J4
T11
V13
V15
P18
J17
Symbol
RSYNC7
RSYNC8
RSYNC9
RSYNC10
RSYNC11
RSYNC12
RSYNC13/NC
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
J19
RSYNC14/NC
I/O
B17
RSYNC15/NC
I/O
B12
RSYNC16/NC
I/O
B5
E2
E5
B8
M4
T2
Y5
W3
T4
Y9
U12
R17
E13
N18
E20
C14
D1
H5
C5
A5
R1
Y3
T6
K2
SYSCLK1
SYSCLK2
SYSCLK3
SYSCLK4
SYSCLK5
SYSCLK6
SYSCLK7
SYSCLK8
SYSCLK9
SYSCLK10
SYSCLK11
SYSCLK12
SYSCLK13/NC
SYSCLK14/NC
SYSCLK15/NC
SYSCLK16/NC
TCLK1
TCLK2
TCLK3
TCLK4
TCLK5
TCLK6
TCLK7
TCLK8
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Description
Receive Frame/Multiframe Sync for Framer 7.
Receive Frame/Multiframe Sync for Framer 8.
Receive Frame/Multiframe Sync for Framer 9.
Receive Frame/Multiframe Sync for Framer 10.
Receive Frame/Multiframe Sync for Framer 11.
Receive Frame/Multiframe Sync for Framer 12.
Receive Frame/Multiframe Sync for Framer 13. NC on
Four x Three.
Receive Frame/Multiframe Sync for Framer 14. NC on
Four x Three.
Receive Frame/Multiframe Sync for Framer 15. NC on
Four x Three.
Receive Frame/Multiframe Sync for Framer 16. NC on
Four x Three.
System Clock for Framer 1.
System Clock for Framer 2.
System Clock for Framer 3.
System Clock for Framer 4.
System Clock for Framer 5.
System Clock for Framer 6.
System Clock for Framer 7.
System Clock for Framer 8.
System Clock for Framer 9.
System Clock for Framer 10.
System Clock for Framer 11.
System Clock for Framer 12.
System Clock for Framer 13. NC on Four x Three.
System Clock for Framer 14. NC on Four x Three.
System Clock for Framer 15. NC on Four x Three.
System Clock for Framer 16. NC on Four x Three.
Transmit Clock for Framer 1.
Transmit Clock for Framer 2.
Transmit Clock for Framer 3.
Transmit Clock for Framer 4.
Transmit Clock for Framer 5.
Transmit Clock for Framer 6.
Transmit Clock for Framer 7.
Transmit Clock for Framer 8.
U13
Y13
T18
P16
K16
F19
E17
C11
TCLK9
TCLK10
TCLK11
TCLK12
TCLK13/NC
TCLK14/NC
TCLK15/NC
TCLK16/NC
I
I
I
I
I
I
I
I
Transmit Clock for Framer 9.
Transmit Clock for Framer 10.
Transmit Clock for Framer 11.
Transmit Clock for Framer 12.
Transmit Clock for Framer 13.
Transmit Clock for Framer 14.
Transmit Clock for Framer 15.
Transmit Clock for Framer 16.
11 of 110
NC on Four x Three.
NC on Four x Three.
NC on Four x Three.
NC on Four x Three.
DS21FT44/DS21FF44
Lead
C3
J1
F5
A10
L1
V2
V8
P5
U14
V12
W18
T19
D11
Symbol
TNEG1
TNEG2
TNEG3
TNEG4
TNEG5
TNEG6
TNEG7
TNEG8
TNEG9
TNEG10
TNEG11
TNEG12
TNEG13/NC
I/O
O
O
O
O
O
O
O
O
O
O
O
O
O
K18
TNEG14/NC
O
C19
TNEG15/NC
O
B15
TNEG16/NC
O
B3
J2
J5
B10
L2
W1
W7
R3
T14
Y10
V18
V20
E12
TPOS1
TPOS2
TPOS3
TPOS4
TPOS5
TPOS6
TPOS7
TPOS8
TPOS9
TPOS10
TPOS11
TPOS12
TPOS13/NC
O
O
O
O
O
O
O
O
O
O
O
O
O
N19
TPOS14/NC
O
B19
TPOS15/NC
O
B14
TPOS16/NC
O
B4
E1
F3
D7
L5
T1
Y6
TSER1
TSER2
TSER3
TSER4
TSER5
TSER6
TSER7
I
I
I
I
I
I
I
Description
Transmit Negative Data from Framer 1.
Transmit Negative Data from Framer 2.
Transmit Negative Data from Framer 3.
Transmit Negative Data from Framer 4.
Transmit Negative Data from Framer 5.
Transmit Negative Data from Framer 6.
Transmit Negative Data from Framer 7.
Transmit Negative Data from Framer 8.
Transmit Negative Data from Framer 9.
Transmit Negative Data from Framer 10.
Transmit Negative Data from Framer 11.
Transmit Negative Data from Framer 12.
Transmit Negative Data from Framer 13. NC on Four x
Three.
Transmit Negative Data from Framer 14. NC on Four x
Three.
Transmit Negative Data from Framer 15. NC on Four x
Three.
Transmit Negative Data from Framer 16. NC on Four x
Three.
Transmit Positive Data from Framer 1.
Transmit Positive Data from Framer 2.
Transmit Positive Data from Framer 3.
Transmit Positive Data from Framer 4.
Transmit Positive Data from Framer 5.
Transmit Positive Data from Framer 6.
Transmit Positive Data from Framer 7.
Transmit Positive Data from Framer 8.
Transmit Positive Data from Framer 9.
Transmit Positive Data from Framer 10.
Transmit Positive Data from Framer 11.
Transmit Positive Data from Framer 12.
Transmit Positive Data from Framer 13. NC on Four x
Three.
Transmit Positive Data from Framer 14. NC on Four x
Three.
Transmit Positive Data from Framer 15. NC on Four x
Three.
Transmit Positive Data from Framer 16. NC on Four x
Three.
Transmit Serial Data for Framer 1.
Transmit Serial Data for Framer 2.
Transmit Serial Data for Framer 3.
Transmit Serial Data for Framer 4.
Transmit Serial Data for Framer 5.
Transmit Serial Data for Framer 6.
Transmit Serial Data for Framer 7.
12 of 110
DS21FT44/DS21FF44
Lead
T3
M16
W9
W16
W20
D13
F17
D18
A18
C4
F1
G4
C10
L3
U2
V9
R5
U15
V10
U18
R18
E11
Symbol
TSER8
TSER9
TSER10
TSER11
TSER12
TSER13/NC
TSER14/NC
TSER15/NC
TSER16/NC
TSIG1
TSIG2
TSIG3
TSIG4
TSIG5
TSIG6
TSIG7
TSIG8
TSIG9
TSIG10
TSIG11
TSIG12
TSIG13/NC
I/O
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
P19
TSIG14/NC
I
B20
TSIG15/NC
I
A16
TSIG16/NC
I
A3
F2
G5
E8
L4
U1
Y7
R4
T15
W8
Y17
U19
C13
TSSYNC1
TSSYNC2
TSSYNC3
TSSYNC4
TSSYNC5
TSSYNC6
TSSYNC7
TSSYNC8
TSSYNC9
TSSYNC10
TSSYNC11
TSSYNC12
TSSYNC13/NC
I
I
I
I
I
I
I
I
I
I
I
I
I
R20
TSSYNC14/NC
I
D20
TSSYNC15/NC
I
Description
Transmit Serial Data for Framer 8.
Transmit Serial Data for Framer 9.
Transmit Serial Data for Framer 10.
Transmit Serial Data for Framer 11.
Transmit Serial Data for Framer 12.
Transmit Serial Data for Framer 13. NC on Four x Three.
Transmit Serial Data for Framer 14. NC on Four x Three.
Transmit Serial Data for Framer 15. NC on Four x Three.
Transmit Serial Data for Framer 16. NC on Four x Three.
Transmit Signaling Input for Framer 1.
Transmit Signaling Input for Framer 2.
Transmit Signaling Input for Framer 3.
Transmit Signaling Input for Framer 4.
Transmit Signaling Input for Framer 5.
Transmit Signaling Input for Framer 6.
Transmit Signaling Input for Framer 7.
Transmit Signaling Input for Framer 8.
Transmit Signaling Input for Framer 9.
Transmit Signaling Input for Framer 10.
Transmit Signaling Input for Framer 11.
Transmit Signaling Input for Framer 12.
Transmit Signaling Input for Framer 13. NC on Four x
Three.
Transmit Signaling Input for Framer 14. NC on Four x
Three.
Transmit Signaling Input for Framer 15. NC on Four x
Three.
Transmit Signaling Input for Framer 16. NC on Four x
Three.
Transmit System Sync for Framer 1.
Transmit System Sync for Framer 2.
Transmit System Sync for Framer 3.
Transmit System Sync for Framer 4.
Transmit System Sync for Framer 5.
Transmit System Sync for Framer 6.
Transmit System Sync for Framer 7.
Transmit System Sync for Framer 8.
Transmit System Sync for Framer 9.
Transmit System Sync for Framer 10.
Transmit System Sync for Framer 11.
Transmit System Sync for Framer 12.
Transmit System Sync for Framer 13. NC on Four x
Three.
Transmit System Sync for Framer 14. NC on Four x
Three.
Transmit System Sync for Framer 15. NC on Four x
Three.
13 of 110
DS21FT44/DS21FF44
Lead
A17
Symbol
TSSYNC16/NC
I/O
I
E3
F4
E7
A4
R2
W5
T5
M5
T13
W13
U16
N16
J16
F18
C15
D12
Y16
TSYNC1
TSYNC2
TSYNC3
TSYNC4
TSYNC5
TSYNC6
TSYNC7
TSYNC8
TSYNC9
TSYNC10
TSYNC11
TSYNC12
TSYNC13/NC
TSYNC14/NC
TSYNC15/NC
TSYNC16/NC
WR*
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I
Description
Transmit System Sync for Framer 16. NC on Four x
Three.
Transmit Sync for Framer 1.
Transmit Sync for Framer 2.
Transmit Sync for Framer 3.
Transmit Sync for Framer 4.
Transmit Sync for Framer 5.
Transmit Sync for Framer 6.
Transmit Sync for Framer 7.
Transmit Sync for Framer 8.
Transmit Sync for Framer 9.
Transmit Sync for Framer 10.
Transmit Sync for Framer 11.
Transmit Sync for Framer 12.
Transmit Sync for Framer 13. NC on Four x Three.
Transmit Sync for Framer 14. NC on Four x Three.
Transmit Sync for Framer 15. NC on Four x Three.
Transmit Sync for Framer 16. NC on Four x Three.
Write Input.
14 of 110
DS21FT44/DS21FF44
3. DS21FF44 (FOUR X FOUR) PCB LAND PATTERNS Figure 3-1
The diagram shown below is the lead pattern that will be placed on the target PCB. This is the same
pattern that would be seen as viewed through the MCM from the top.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
A
rpos
1
rclk
1
ts
sync1
tsync
4
tclk
4
dvss
1
rsync
4
rneg
4
tneg
4
dvss
4
rser
16
test
rpos
16
rsig
16
tsig
16
jtdof
rpos
15
rsync
1
rneg
1
tpos
1
tser
1
clksi
8
mclk
rclk
4
tpos
4
dvdd
4
rsync
16
rneg
16
tpos
16
tneg
16
tneg
1
tsig
1
rser
3
dvdd
1
rpos
4
tsig
4
tclk
16
rclk
16
tneg
15
rneg
15
rsig
1
rsig
3
dvss
1
rsync
3
tser
4
rsig4
rneg
3
rclk
3
tneg
13
tsync
16
sys
clk
16
rclk
13
rsig
15
tclk
1
ts
sync
13
tser
13
tsync
15
D
rch
blk
1
dvdd
1
rch
blk
15
rclk
15
tsig
15
rser
1
rch
blk
16
rser
15
tpos
15
C
sys
clk
1
tclk
3
ts
sync
16
rsync
15
tser
16
B
rch
blk
4
sys
clk
4
rser4
dvdd
4
tser
15
dvss
4
E
tser
2
tsync
1
dvdd
1
tsync
3
ts
sync
4
dvss
1
jtdi
tsig
13
tpos
13
sys
clk
13
rneg
13
rsig
13
tclk
15
rd*
cs4*
tsig
2
tser
3
tsync
2
sys
clk
3
tneg
3
rch
blk
3
F
dvdd
4
tser
14
tsync
14
tclk
14
ts
sync
15
sys
clk
15
rser
14
G
rsync
2
sys
clk
2
ts
sync
2
rsig
2
rch
blk
13
rser
13
tsig
3
A6
A4
A2
A0
rpos
2
rneg
2
rpos
3
ts
sync
3
tclk
2
int*
H
rch
blk
2
rser
2
jtms
A7
A5
A3
A1
J
tneg
2
tpos
2
rclk
8
rsync
8
tpos
3
tsync
13
rsync
13
rpos
14
rsync
14
dvss
4
K
rclk
2
tclk
8
dvdd
2
dvss
2
rsig
8
tclk
13
jtrst*
tneg
14
rsig
14
L
tneg
5
tpos
5
tsig
5
tser
5
dvdd
3
D6
D4
D2
M
rpos
5
rneg
5
rclk
5
tsync
8
tser
9
D7
D5
D3
D1
N
rsig
5
rsync
5
rclk
12
rneg
14
rneg
8
rpos
8
tclk
12
mux
sys
clk
14
rsync
12
tpos
14
dvdd
2
rch
blk
8
tneg
8
tsync
12
P
rch
blk
5
rser
5
ts
sync
5
sys
clk
5
rser
8
rch
blk
14
D0
tsig
14
rclk
14
R
tclk
5
tsync
5
tpos
8
tsig
8
dvss
3
rpos
12
tser
6
tser
8
tsync
7
tclk
7
rser
7
cs1*
rclk
9
rpos
9
rsync
9
dvdd
3
tsync
9
tpos
9
tclk
11
tneg
12
ts
sync
14
rneg
12
U
dvss
2
rsync
7
dvss
2
rneg
9
rsig
9
rser
9
tneg
9
tssync
12
rsig
12
rsig
6
rpos
7
rneg
7
tneg
7
tsig
7
tsig
10
rpos
10
rsync
10
tpos
11
dvdd
3
tpos
12
W
tpos
6
rpos
6
rser
6
tsync
6
rclk
7
tpos
7
rclk
10
rneg
10
tneg
11
rsig
11
tser
12
rch
blk
6
rsync
6
cs2*
sys
clk
7
tser
7
ts
sync
7
ts
sync
10
rch
blk
9
tser
10
Y
sys
clk
8
tclk
6
rch
blk
12
rch
blk
11
rneg
11
tsig
11
rneg
6
sys
clk
11
tneg
10
tclk
9
tneg
6
rch
blk
7
rsig
7
dvdd
2
V
ts
sync
6
rclk
6
sys
clk
6
tsig
6
sys
clk
12
jtdot
tsig
12
T
ts
sync
8
sys
clk
9
dvss
3
sys
clk
10
tpos
10
rsig
10
rclk
11
rpos
11
dvss
3
15 of 110
rch
blk
10
rser
10
rpos
13
ts
sync
9
tsig
9
rser
12
tsync
11
jtclk
rsync
11
rser
11
tsync
10
fs1
bts
tser
11
tclk
10
fs0
cs3*
wr*
ts
sync
11
DS21FT44/DS21FF44
4. DS21FT44 (Four x Three) PCB Land Pattern Figure 4-1
The diagram shown below is the lead pattern that will be placed on the target PCB. This is the same
pattern that would be seen as viewed through the MCM from the top.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
A
rpos
1
rclk
1
ts
sync1
tsync
4
tclk
4
dvss
1
rsync
4
rneg
4
tneg
4
nc
nc
test
ns
ns
nc
nc
nc
nc
nc
B
rsync
1
rneg
1
tpos
1
tser
1
clksi
8
mclk
rclk
4
tpos
4
nc
nc
nc
nc
nc
nc
nc
nc
nc
nc
C
rser
1
tneg
1
tsig
1
rser
3
dvdd
1
rpos
4
tsig
4
nc
nc
nc
nc
ns
nc
nc
nc
nc
nc
D
tclk
1
rch
blk
1
dvdd
1
sys
clk
1
tclk
3
rch
blk
4
sys
clk
4
rser4
rsig
1
rsig
3
dvss
1
rsync
3
tser
4
rsig4
rneg
3
rclk
3
nc
nc
nc
nc
nc
nc
nc
nc
nc
nc
E
tser
2
tsync
1
dvdd
1
tsync
3
ts
sync
4
dvss
1
jtdi
nc
nc
nc
nc
nc
nc
nc
rd*
nc
nc
tsig
2
tser
3
tsync
2
sys
clk
3
tneg
3
rch
blk
3
F
nc
nc
nc
nc
nc
G
rsync
2
sys
clk
2
ts
sync
2
rsig
2
tsig
3
A6
A4
A2
A0
rpos
2
rneg
2
rpos
3
ts
sync
3
tclk
2
int*
H
rch
blk
2
rser
2
jtms
A7
A5
A3
A1
J
tneg
2
tpos
2
rclk
8
rsync
8
tpos
3
nc
nc
nc
nc
nc
K
rclk
2
tclk
8
dvdd
2
dvss
2
rsig
8
nc
jtrst*
nc
nc
nc
L
tneg
5
tpos
5
tsig
5
tser
5
dvdd
3
D6
D4
D2
D0
M
rpos
5
rneg
5
rclk
5
tsync
8
tser
9
D7
D5
D3
D1
N
rsig
5
rsync
5
rclk
12
nc
nc
nc
dvdd
2
rneg
8
rpos
8
rch
blk
8
tneg
8
tsync
12
P
rch
blk
5
rser
5
ts
sync
5
sys
clk
5
rser
8
tclk
12
mux
rsync
12
nc
nc
R
tclk
5
tsync
5
tpos
8
tsig
8
dvss
3
rpos
12
nc
tser
6
tser
8
tsync
7
tclk
7
rser
7
cs1*
rclk
9
rpos
9
rsync
9
dvdd
3
tsync
9
tpos
9
tclk
11
tneg
12
rneg
12
U
dvss
2
rsync
7
dvss
2
rneg
9
rsig
9
rser
9
tneg
9
tssync
12
rsig
12
rsig
6
rpos
7
rneg
7
tneg
7
tsig
7
tsig
10
rpos
10
rsync
10
tpos
11
dvdd
3
tpos
12
W
tpos
6
rpos
6
rser
6
tsync
6
rclk
7
tpos
7
rclk
10
rneg
10
tneg
11
rsig
11
tser
12
rch
blk
6
rsync
6
cs2*
sys
clk
7
tser
7
ts
sync
7
ts
sync
10
rch
blk
9
tser
10
Y
sys
clk
8
tclk
6
rch
blk
12
rch
blk
11
rneg
11
tsig
11
rneg
6
sys
clk
11
tneg
10
tclk
9
tneg
6
rch
blk
7
rsig
7
dvdd
2
V
ts
sync
6
rclk
6
sys
clk
6
tsig
6
sys
clk
12
jtdot
tsig
12
T
ts
sync
8
sys
clk
9
dvss
3
sys
clk
10
tpos
10
rsig
10
rclk
11
rpos
11
dvss
3
16 of 110
rch
blk
10
rser
10
ts
sync
9
tsig
9
rser
12
tsync
11
jtclk
rsync
11
rser
11
tsync
10
fs1
bts
tser
11
tclk
10
fs0
cs3*
wr*
ts
sync
11
DS21FT44/DS21FF44
5. DS21Q44 DIE DESCRIPTION
FEATURES
·
·
·
·
·
·
·
·
·
·
·
·
·
·
·
FUNCTIONAL DIAGRAM
Four E1 (CEPT or PCM-30) /ISDN-PRI
framing transceivers
All four framers are fully independent;
transmit and receive sections of each
framer are fully independent
Frames to FAS, CAS, CCS, and CRC4
formats
Each of the four framers contain dual two–
frame elastic store slip buffers that can
connect to asynchronous backplanes up to
8.192 MHz
8–bit parallel control port that can be used
directly on either multiplexed or non–
multiplexed buses (Intel or Motorola)
Easy access to Si and Sa bits
Extracts and inserts CAS signaling
Large counters for bipolar and code
violations, CRC4 code word errors, FAS
word errors, and E-bits
Programmable output clocks for Fractional
E1, per channel loopback, H0 and H12
applications
Integral HDLC controller with 64-byte
buffers. Configurable for Sa bits or DS0
operation
Detects and generates AIS, remote alarm,
and remote multiframe alarms
Pin compatible with DS21Q42 Enhanced
Quad T1 Framer
3.3V supply with 5V tolerant I/O; low
power CMOS
Available in 128–pin TQFP package
IEEE 1149.1 support
Receive
Framer
Elastic
Store
Transmit
Formatter
Elastic
Store
FRAMER #0
FRAMER #1
FRAMER #2
FRAMER #3
Control Port
DESCRIPTION
The DS21Q44 E1 is an enhanced version of the DS21Q43 Quad E1 Framer. The DS21Q44 contains four
framers that are configured and read through a common microprocessor compatible parallel port. Each
framer consists of a receive framer, receive elastic store, transmit formatter and transmit elastic store. All
four framers in the DS21Q44 are totally independent, they do not share a common framing synchronizer.
Also the transmit and receive sides of each framer are totally independent. The dual two-frame elastic
stores contained in each of the four framers can be independently enabled and disabled as required. The
device fully meets all of the latest E1 specifications including CCITT/ITU G.704, G.706, G.962, and
I.431 as well as ETS 300 011 and ETS 300 233.
17 of 110
DS21FT44/DS21FF44
6. DS21Q44 INTRODUCTION
The DS21Q44 is a superset version of the popular DS21Q43 Quad E1 framer offering the new features
listed below. All of the original features of the DS21Q43 have been retained and software created for the
original device is transferable to the DS21Q44.
New Features
·
·
·
·
·
·
·
·
·
Aditional hardware signaling capability including:
– receive signaling reinsertion to a backplane multiframe sync
– availability of signaling in a separate PCM data stream
– signaling freezing
– interrupt generated on change of signaling data
Per–channel code insertion in both transmit and receive paths
Full HDLC controller with 64–byte buffers in both transmit and receive paths. Configurable for
Sa bits or DS0 access
RCL, RLOS, RRA, and RUA1 alarms now interrupt on change of state
8.192 MHz clock synthesizer
Ability to monitor one DS0 channel in both the transmit and receive paths
Option to extend carrier loss criteria to a 1 ms period as per ETS 300 233
Automatic RAI generation to ETS 300 011 specifications
IEEE 1149.1 support
Functional Description
The receive side in each framer locates FAS frame and CRC and CAS multiframe boundaries as well as
detects incoming alarms including, carrier loss, loss of synchronization, AIS and Remote Alarm. If
needed, the receive side elastic store can be enabled in order to absorb the phase and frequency
differences between the recovered E1 data stream and an asynchronous backplane clock which is
provided at the RSYSCLK input. The clock applied at the RSYSCLK input can be either a 2.048 MHz
clock or a 1.544 MHz clock. The RSYSCLK can be a burst clock with speeds up to 8.192 MHz.
The transmit side in each framer is totally independent from the receive side in both the clock
requirements and characteristics. Data off of a backplane can be passed through a transmit side elastic
store if necessary. The transmit formatter will provide the necessary frame/multiframe data overhead for
E1 transmission.
18 of 110
DS21FT44/DS21FF44
Reader’s Note:
This data sheet assumes a particular nomenclature of the E1 operating environment. In each 125 us
frame, there are 32 8-bit timeslots numbered 0 to 31. Timeslot 0 is transmitted first and received first.
These 32 timeslots are also referred to as channels with a numbering scheme of 1 to 32. Timeslot 0 is
identical to channel 1, timeslot 1 is identical to Channel 2, and so on. Each timeslot (or channel) is made
up of 8 bits which are numbered 1 to 8. Bit number 1 is the MSB and is transmitted first. Bit number 8 is
the LSB and is transmitted last. Throughout this data sheet, the following abbreviations will be used:
FAS
CAS
MF
Si
CRC4
CCS
Sa
E-bit
Frame Alignment Signal
Channel Associated Signaling
Multiframe
International bits
Cyclical Redundancy Check
Common Channel Signaling
Additional bits
CRC4 Error Bits
19 of 110
DS21FT44/DS21FF44
DS21Q44 ENHANCED QUAD E1 FRAMER Figure 6-1
RLOS/LOTC 1
64-Byte Buffer
HDLC Engine
DS0 Insertion
RLINK
RLCLK
Sa Extraction
RCHBLK
RCHCLK 1
Timing Control
Signaling
Buffer
Signaling Extraction
SA and SI Extraction
FAS Error Counter
E-BIT Counter
Per-Channel Code Insert
Remote Loopback
Framer Loopback
RNEG
CRC Error Counter
RPOS
RCLK
BPV Counter
Synchronizer
Alarm Detection
HDB3 Decoder
Receive Side Framer
RSIG
RSER
data
clock
sync
RSYSCLK
RSYNC
RMSYNC 1
Elastic
Store
RFSYNC
TSYNC
Sync Control
Per-Channel Code Insert
FAS Word Insertion
Per-Channel Loopback
SI Bit Insertion
Signaling Insertion
SA Insertion
E-Bit Insertion
TNEG
HDB3 Encode
CRC4 Generation
AIS Generation
TPOS
TCHBLK
Timing Control
Transmit Side Formatter
sync
clock
TCHCLK
TSSYNC
Elastic
Store
data
TSYSCLK
Hardware
Signaling
Insertion
TSER
TSIG
LOTC DET
&
MUX
64-Byte Buffer
TCLK
HDLC Engine
DS0 Insertion
TLINK
TLCLK
Sa Insertion
FRAMER #0
FRAMER #1
FRAMER #2
FRAMER #3
8.192MHz Clock
Synthesizer
CLKS I
VDD
VSS
8MCLK
JTRST*
3
JTMS
Power
3
JTCLK
JTAG Port
JTDI
JTDO
Parallel & Test Control Port
(routed to all blocks)
8
7
TEST
CS*
FS0
FS1
BTS
WR*
(R/W*)
RD*
(DS*)
ALE
(AS)/
A6
A0 to A5,
A7
Note:
1. Alternate pin functions. Consult data sheet for restrictions.
20 of 110
MUX
1
D0 to D7 /
AD0 to AD7
FMS
INT*
DS21FT44/DS21FF44
7. DS21Q44 PIN FUNCTION DESCRIPTION
This section describes the signals on the DS21Q44 die. Signals which are not bonded out or have limited
functionality in the DS21FT44 and DS21FF44 are noted in italics.
TRANSMIT SIDE PINS
Signal Name:
TCLK
Signal Description:
Transmit Clock
Signal Type:
Input
A 2.048 MHz primary clock. Used to clock data through the transmit side formatter.
Signal Name:
TSER
Signal Description:
Transmit Serial Data
Signal Type:
Input
Transmit NRZ serial data. Sampled on the falling edge of TCLK when the transmit side elastic store is
disabled. Sampled on the falling edge of TSYSCLK when the transmit side elastic store is enabled.
Signal Name:
TCHCLK
Signal Description:
Transmit Channel Clock
Signal Type:
Output
A 256 KHz clock which pulses high during the LSB of each channel. Synchronous with TCLK when the
transmit side elastic store is disabled. Synchronous with TSYSCLK when the transmit side elastic store
is enabled. Useful for parallel to serial conversion of channel data. This function is available when FMS
= 1 (DS21Q43 emulation). This signal is not bonded out in the DS21FF44/DS21FT44.
Signal Name:
TCHBLK
Signal Description:
Transmit Channel Block
Signal Type:
Output
A user programmable output that can be forced high or low during any of the 32 E1 channels.
Synchronous with TCLK when the transmit side elastic store is disabled. Synchronous with TSYSCLK
when the transmit side elastic store is enabled. Useful for blocking clocks to a serial UART or LAPD
controller in applications where not all E1 channels are used such as Fractional E1, 384 Kbps (H0), 768
Kbps, 1920 bps (H12) or ISDN–PRI . Also useful for locating individual channels in drop–and–insert
applications, for external per–channel loopback, and for per–channel conditioning. See Section 16 for
details. This signal is not bonded out in the DS21FF44/DS21FT44.
Signal Name:
TSYSCLK
Signal Description:
Transmit System Clock
Signal Type:
Input
1.544 MHz or 2.048 MHz clock. Only used when the transmit side elastic store function is enabled.
Should be tied low in applications that do not use the transmit side elastic store. Can be burst at rates up
to 8.192 MHz. This pin is tied to the RSYSCLK signal in the DS21FF44/DS21FT44.
Signal Name:
TLCLK
Signal Description:
Transmit Link Clock
Signal Type:
Output
4 KHz to 20 KHz demand clock for the TLINK input. See Section 18 for details. This signal is not
bonded out in the DS21FF44/DS21FT44.
21 of 110
DS21FT44/DS21FF44
Signal Name:
TLINK
Signal Description:
Transmit Link Data
Signal Type:
Input
If enabled, this pin will be sampled on the falling edge of TCLK for data insertion into any combination
of the Sa bit positions (Sa4 to Sa8). See Section 18 for details. This signal is not bonded out in the
DS21FF44/DS21FT44.
Signal Name:
TSYNC
Signal Description:
Transmit Sync
Signal Type:
Input /Output
A pulse at this pin will establish either frame or multiframe boundaries for the transmit side. This pin can
also be programmed to output either a frame or multiframe pulse. Always synchronous with TCLK.
Signal Name:
TSSYNC
Signal Description:
Transmit System Sync
Signal Type:
Input
Only used when the transmit side elastic store is enabled. A pulse at this pin will establish either frame or
multiframe boundaries for the transmit side. Should be tied low in applications that do not use the
transmit side elastic store. Always synchronous with TSYSCLK.
Signal Name:
TSIG
Signal Description:
Transmit Signaling Input
Signal Type:
Input
When enabled, this input will sample signaling bits for insertion into outgoing PCM E1 data stream.
Sampled on the falling edge of TCLK when the transmit side elastic store is disabled. Sampled on the
falling edge of TSYSCLK when the transmit side elastic store is enabled. This function is available when
FMS = 0. FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
TPOS
Signal Description:
Transmit Positive Data Output
Signal Type:
Output
Updated on the rising edge of TCLK with the bipolar data out of the transmit side formatter. Can be
programmed to source NRZ data via the Output Data Format (TCR1.7) control bit.
Signal Name:
TNEG
Signal Description:
Transmit Negative Data Output
Signal Type:
Output
Updated on the rising edge of TCLK with the bipolar data out of the transmit side formatter.
RECEIVE SIDE PINS
Signal Name:
RLINK
Signal Description:
Receive Link Data
Signal Type:
Output
Updated with full recovered E1 data stream on the rising edge of RCLK. This signal is not bonded out in
the DS21FF44/DS21FT44.
22 of 110
DS21FT44/DS21FF44
Signal Name:
RLCLK
Signal Description:
Receive Link Clock
Signal Type:
Output
A 4 KHz to 20 KHz clock for the RLINK output. Used for sampling Sa bits. This signal is not bonded
out in the DS21FF44/DS21FT44.
Signal Name:
RCLK
Signal Description:
Receive Clock Input
Signal Type:
Input
2.048 MHz clock that is used to clock data through the receive side framer.
Signal Name:
RCHCLK
Signal Description:
Receive Channel Clock
Signal Type:
Output
A 256 KHz clock which pulses high during the LSB of each channel. Synchronous with RCLK when
the receive side elastic store is disabled. Synchronous with RSYSCLK when the receive side elastic store
is enabled. Useful for parallel to serial conversion of channel data. This function is available when FMS
= 1 (DS21Q43 emulation). This signal is not bonded out in the DS21FF44/DS21FT44.
Signal Name:
RCHBLK
Signal Description:
Receive Channel Block
Signal Type:
Output
A user programmable output that can be forced high or low during any of the 32 E1 channels.
Synchronous with RCLK when the receive side elastic store is disabled. Synchronous with RSYSCLK
when the receive side elastic store is enabled. Useful for blocking clocks to a serial UART or LAPD
controller in applications where not all E1 channels are used such as Fractional E1, 384K bps service,
768K bps, or ISDN–PRI. Also useful for locating individual channels in drop–and–insert applications,
for external per–channel loopback, and for per–channel conditioning. See Section 16 for details.
Signal Name:
RSER
Signal Description:
Receive Serial Data
Signal Type:
Output
Received NRZ serial data. Updated on rising edges of RCLK when the receive side elastic store is
disabled. Updated on the rising edges of RSYSCLK when the receive side elastic store is enabled.
Signal Name:
RSYNC
Signal Description:
Receive Sync
Signal Type:
Input /Output
An extracted pulse, one RCLK wide, is output at this pin which identifies either frame or CAS/CRC
multiframe boundaries. If the receive side elastic store is enabled, then this pin can be enabled to be an
input at which a frame or multiframe boundary pulse synchronous with RSYSCLK is applied.
Signal Name:
RFSYNC
Signal Description:
Receive Frame Sync
Signal Type:
Output
An extracted 8 KHz pulse, one RCLK wide, is output at this pin which identifies frame boundaries. This
signal is not bonded out in the DS21FF44/DS21FT44.
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DS21FT44/DS21FF44
Signal Name:
RMSYNC
Signal Description:
Receive Multiframe Sync
Signal Type:
Output
An extracted pulse, one RSYSCLK wide, is output at this pin which identifies multiframe boundaries. If
the receive side elastic store is disabled, then this output will output multiframe boundaries associated
with RCLK. This function is available when FMS = 1 (DS21Q43 emulation). This signal is not bonded
out in the DS21FF44/DS21FT44.
Signal Name:
RSYSCLK
Signal Description:
Receive System Clock
Signal Type:
Input
1.544 MHz or 2.048 MHz clock. Only used when the elastic store function is enabled. Should be tied
low in applications that do not use the elastic store. Can be burst at rates up to 8.192 MHz. This pin is
tied to the TSYSCLK signal in the DS21FF44/DS21FT44.
Signal Name:
RSIG
Signal Description:
Receive Signaling Output
Signal Type:
Output
Outputs signaling bits in a PCM format. Updated on rising edges of RCLK when the receive side elastic
store is disabled. Updated on the rising edges of RSYSCLK when the receive side elastic store is
enabled. This function is available when FMS = 0. FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
RLOS/LOTC
Signal Description:
Receive Loss of Sync / Loss of Transmit Clock
Signal Type:
Output
A dual function output that is controlled by the TCR2.0 control bit. This pin can be programmed to either
toggle high when the synchronizer is searching for the frame and multiframe or to toggle high if the
TCLK pin has not been toggled for 5 usec. This function is available when FMS = 1 (DS21Q43
emulation). This signal is not bonded out in the DS21FF44/DS21FT44.
Signal Name:
CLKSI
Signal Description:
8 MHz Clock Reference
Signal Type:
Input
A 2.048 MHz reference clock used in the generation of 8MCLK. This function is available when FMS =
0. FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
8MCLK
Signal Description:
8 MHz Clock
Signal Type:
Output
A 8.192 MHz output clock that is referenced to the clock that is input at the CLKSI pin. This function is
available when FMS = 0. FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
RPOS
Signal Description:
Receive Positive Data Input
Signal Type:
Input
Sampled on the falling edge of RCLK for data to be clocked through the receive side framer. RPOS and
RNEG can be tied together for an NRZ interface. Connecting RPOS to RNEG disables the bipolar
violation monitoring circuitry.
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DS21FT44/DS21FF44
Signal Name:
RNEG
Signal Description:
Receive Negative Data Input
Signal Type:
Input
Sampled on the falling edge of RCLK for data to be clocked through the receive side framer. RPOS and
RNEG can be tied together for an NRZ interface. Connecting RPOS to RNEG disables the bipolar
violation monitoring circuitry.
PARALLEL CONTROL PORT PINS
Signal Name:
INT*
Signal Description:
Interrupt
Signal Type:
Output
Flags host controller during conditions and change of conditions defined in the Status Registers 1 and 2
and the FDL Status Register. Active low, open drain output.
Signal Name:
FMS
Signal Description:
Framer Mode Select
Signal Type:
Input
Set low to select DS21Q44 feature set. Set high to select DS21Q43 emulation. FMS is tied to ground for
the DS21FF44/DS21FT44.
Signal Name:
MUX
Signal Description:
Bus Operation
Signal Type:
Input
Set low to select non–multiplexed bus operation. Set high to select multiplexed bus operation.
Signal Name:
D0 to D7 / AD0 to AD7
Signal Description:
Data Bus or Address/Data Bus
Signal Type:
Input /Output
In non–multiplexed bus operation (MUX = 0), serves as the data bus. In multiplexed bus operation
(MUX = 1), serves as a 8–bit multiplexed address / data bus.
Signal Name:
A0 to A5, A7
Signal Description:
Address Bus
Signal Type:
Input
In non–multiplexed bus operation (MUX = 0), serves as the address bus. In multiplexed bus operation
(MUX = 1), these pins are not used and should be tied low.
Signal Name:
ALE (AS) / A6
Signal Description:
Address Latch Enable (Address Strobe) or A6
Signal Type:
Input
In non–multiplexed bus operation (MUX = 0), serves as address bit 6. In multiplexed bus operation
(MUX = 1), serves to demultiplex the bus on a positive–going edge.
Signal Name:
BTS
Signal Description:
Bus Type Select
Signal Type:
Input
Strap high to select Motorola bus timing; strap low to select Intel bus timing. This pin controls the
function of the RD*(DS*), ALE(AS), and WR*(R/W*) pins. If BTS = 1, then these pins assume the
function listed in parenthesis ().
25 of 110
DS21FT44/DS21FF44
Signal Name:
Signal Description:
Signal Type:
RD* and DS* are active
diagrams in section 23 .
RD* (DS*)
Read Input (Data Strobe)
Input
low signals. Note: DS is active high when MUX=1. Refer to bus timing
Signal Name:
FS0 and FS1
Signal Description:
Framer Selects
Signal Type:
Input
Selects which of the four framers to be accessed.
Signal Name:
CS*
Signal Description:
Chip Select
Signal Type:
Input
Must be low to read or write to the device. CS* is an active low signal.
Signal Name:
WR* (R/W*)
Signal Description:
Write Input (Read/Write)
Signal Type:
Input
WR* is an active low signal.
TEST ACCESS PORT PINS
Signal Name:
Test
Signal Description:
3–State Control
Signal Type:
Input
Set high to 3–state all output and I/O pins (including the parallel control port). Set low for normal
operation. Useful in board level testing.
Signal Name:
JTRST*
Signal Description:
IEEE 1149.1 Test Reset
Signal Type:
Input
This signal is used to asynchronously reset the test access port controller. At power up, JTRST* must be
set low and then high. This action will set the device into the boundary scan bypass mode allowing
normal device operation. If boundary scan is not used, this pin should be held low. This function is
available when FMS = 0. FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
JTMS
Signal Description:
IEEE 1149.1 Test Mode Select
Signal Type:
Input
This pin is sampled on the rising edge of JTCLK and is used to place the test port into the various defined
IEEE 1149.1 states. If not used, this pin should be pulled high. This function is available when FMS = 0.
FMS is tied to ground for the DS21FF44/DS21FT44.
Signal Name:
JTCLK
Signal Description:
IEEE 1149.1 Test Clock Signal
Signal Type:
Input
This signal is used to shift data into JTDI on the rising edge and out of JTDO on the falling edge. If not
used, this pin should be tied to VSS. This function is available when FMS = 0.
26 of 110
DS21FT44/DS21FF44
Signal Name:
JTDI
Signal Description:
IEEE 1149.1 Test Data Input
Signal Type:
Input
Test instructions and data are clocked into this pin on the rising edge of JTCLK. If not used, this pin
should be pulled high. This function is available when FMS = 0. FMS is tied to ground for the
DS21FF44/DS21FT44.
Signal Name:
JTDO
Signal Description:
IEEE 1149.1 Test Data Output
Signal Type:
Output
Test instructions and data are clocked out of this pin on the falling edge of JTCLK. If not used, this pin
should be left unconnected. This function is available when FMS = 0. FMS is tied to ground for the
DS21FF44/DS21FT44.
SUPPLY PINS
Signal Name:
Signal Description:
Signal Type:
2.97 to 3.63 volts.
VDD
Positive Supply
Supply
Signal Name:
Signal Description:
Signal Type:
0.0 volts.
VSS
Signal Ground
Supply
8. DS21Q44 REGISTER MAP
Register Map Sorted by Address Table 8-1
ADDRESS
00
01
02
R/W
R
R
R
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
R
R
R
R/W
R/W
R/W
R/W
–
–
–
–
–
R
R/W
R/W
REGISTER NAME
BPV or Code Violation Count 1
BPV or Code Violation Count 2
CRC4 Error Count 1 / FAS Error
Count 1
CRC4 Error Count 2
E-Bit Count 1 / FAS Error Count 2
E-Bit Count 2
Status 1
Status 2
Receive Information
Test 2
Not used
Not used
Not used
Not used
Not used
Device ID
Receive Control 1
Receive Control 2
27 of 110
REGISTER ABBREVIATION
VCR1
VCR2
CRCCR1
CRCCR2
EBCR1
EBCR2
SR1
SR2
RIR
TEST2 (set to 00h)
(set to 00H)
(set to 00H)
(set to 00H)
(set to 00H)
(set to 00H)
IDR
RCR1
RCR2
DS21FT44/DS21FF44
ADDRESS
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
R/W
R/W
R/W
R/W
R/W
R/W
R/W
–
–
R/W
R/W
R/W
R/W
R
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
REGISTER NAME
Transmit Control 1
Transmit Control 2
Common Control 1
Test 1
Interrupt Mask 1
Interrupt Mask 2
Not used
Not used
Common Control 2
Common Control 3
Transmit Sa Bit Control
Common Control 6
Synchronizer Status
Receive Non-Align Frame
Transmit Align Frame
Transmit Non-Align Frame
Transmit Channel Blocking 1
Transmit Channel Blocking 2
Transmit Channel Blocking 3
Transmit Channel Blocking 4
Transmit Idle 1
Transmit Idle 2
Transmit Idle 3
Transmit Idle 4
Transmit Idle Definition
Receive Channel Blocking 1
Receive Channel Blocking 2
Receive Channel Blocking 3
Receive Channel Blocking 4
Receive Align Frame
Receive Signaling 1
Receive Signaling 2
Receive Signaling 3
Receive Signaling 4
Receive Signaling 5
Receive Signaling 6
Receive Signaling 7
Receive Signaling 8
Receive Signaling 9
Receive Signaling 10
Receive Signaling 11
Receive Signaling 12
Receive Signaling 13
Receive Signaling 14
Receive Signaling 15
Receive Signaling 16
28 of 110
REGISTER ABBREVIATION
TCR1
TCR2
CCR1
TEST1 (set to 00h)
IMR1
IMR2
(set to 00H)
(set to 00H)
CCR2
CCR3
TSaCR
CCR6
SSR
RNAF
TAF
TNAF
TCBR1
TCBR2
TCBR3
TCBR4
TIR1
TIR2
TIR3
TIR4
TIDR
RCBR1
RCBR2
RCBR3
RCBR4
RAF
RS1
RS2
RS3
RS4
RS5
RS6
RS7
RS8
RS9
RS10
RS11
RS12
RS13
RS14
RS15
RS16
DS21FT44/DS21FF44
ADDRESS
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R
R
R
R
R
R
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
REGISTER NAME
Transmit Signaling 1
Transmit Signaling 2
Transmit Signaling 3
Transmit Signaling 4
Transmit Signaling 5
Transmit Signaling 6
Transmit Signaling 7
Transmit Signaling 8
Transmit Signaling 9
Transmit Signaling 10
Transmit Signaling 11
Transmit Signaling 12
Transmit Signaling 13
Transmit Signaling 14
Transmit Signaling 15
Transmit Signaling 16
Transmit Si Bits Align Frame
Transmit Si Bits Non-Align Frame
Transmit Remote Alarm Bits
Transmit Sa4 Bits
Transmit Sa5 Bits
Transmit Sa6 Bits
Transmit Sa7 Bits
Transmit Sa8 Bits
Receive Si bits Align Frame
Receive Si bits Non-Align Frame
Receive Remote Alarm Bits
Receive Sa4 Bits
Receive Sa5 Bits
Receive Sa6 Bits
Receive Sa7 Bits
Receive Sa8 Bits
Transmit Channel 1
Transmit Channel 2
Transmit Channel 3
Transmit Channel 4
Transmit Channel 5
Transmit Channel 6
Transmit Channel 7
Transmit Channel 8
Transmit Channel 9
Transmit Channel 10
Transmit Channel 11
Transmit Channel 12
Transmit Channel 13
Transmit Channel 14
29 of 110
REGISTER ABBREVIATION
TS1
TS2
TS3
TS4
TS5
TS6
TS7
TS8
TS9
TS10
TS11
TS12
TS13
TS14
TS15
TS16
TSiAF
TSiNAF
TRA
TSa4
TSa5
TSa6
TSa7
TSa8
RSiAF
RSiNAF
RRA
RSa4
RSa5
RSa6
RSa7
RSa8
TC1
TC2
TC3
TC4
TC5
TC6
TC7
TC8
TC9
TC10
TC11
TC12
TC13
TC14
DS21FT44/DS21FF44
ADDRESS
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
80
81
82
83
84
85
86
87
88
89
8A
8B
8C
8D
8E
8F
90
91
92
93
94
95
96
97
98
99
9A
9B
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
REGISTER NAME
Transmit Channel 15
Transmit Channel 16
Transmit Channel 17
Transmit Channel 18
Transmit Channel 19
Transmit Channel 20
Transmit Channel 21
Transmit Channel 22
Transmit Channel 23
Transmit Channel 24
Transmit Channel 25
Transmit Channel 26
Transmit Channel 27
Transmit Channel 28
Transmit Channel 29
Transmit Channel 30
Transmit Channel 31
Transmit Channel 32
Receive Channel 1
Receive Channel 2
Receive Channel 3
Receive Channel 4
Receive Channel 5
Receive Channel 6
Receive Channel 7
Receive Channel 8
Receive Channel 9
Receive Channel 10
Receive Channel 11
Receive Channel 12
Receive Channel 13
Receive Channel 14
Receive Channel 15
Receive Channel 16
Receive Channel 17
Receive Channel 18
Receive Channel 19
Receive Channel 20
Receive Channel 21
Receive Channel 22
Receive Channel 23
Receive Channel 24
Receive Channel 25
Receive Channel 26
Receive Channel 27
Receive Channel 28
30 of 110
REGISTER ABBREVIATION
TC15
TC16
TC17
TC18
TC19
TC20
TC21
TC22
TC23
TC24
TC25
TC26
TC27
TC28
TC29
TC30
TC31
TC32
RC1
RC2
RC3
RC4
RC5
RC6
RC7
RC8
RC9
RC10
RC11
RC12
RC13
RC14
RC15
RC16
RC17
RC18
RC19
RC20
RC21
RC22
RC23
RC24
RC25
RC26
RC27
RC28
DS21FT44/DS21FF44
ADDRESS
9C
9D
9E
9F
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
AA
AB
AC
AD
AE
AF
B0
B1
B2
B3
B4
B5
B6
B7
B8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R/W
R
R/W
–
–
–
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
B9
R/W
BA
R/W
BB
R/W
BC
BD
BE
BF
–
–
–
–
REGISTER NAME
REGISTER ABBREVIATION
Receive Channel 29
RC29
Receive Channel 30
RC30
Receive Channel 31
RC31
Receive Channel 32
RC32
Transmit Channel Control 1
TCC1
Transmit Channel Control 2
TCC2
Transmit Channel Control 3
TCC3
Transmit Channel Control 4
TCC4
Receive Channel Control 1
RCC1
Receive Channel Control 2
RCC2
Receive Channel Control 3
RCC3
Receive Channel Control 4
RCC4
Common Control 4
CCR4
Transmit DS0 Monitor
TDS0M
Common Control 5
CCR5
Receive DS0 Monitor
RDS0M
Test 3
TEST3 (set to 00H)
Not used
(set to 00H)
Not used
(set to 00H)
Not used
(set to 00H)
HDLC Control Register
HCR
HDLC Status Register
HSR
HDLC Interrupt Mask Register
HIMR
Receive HDLC Information Register
RHIR
Receive HDLC FIFO Register
RHFR
Interleave Bus Operation Register
IBO
Transmit HDLC Information Register
THIR
Transmit HDLC FIFO Register
THFR
Receive HDLC DS0 Control
RDC1
Register 1
Receive HDLC DS0 Control
RDC2
Register 2
Transmit HDLC DS0 Control
TDC1
Register 1
Transmit HDLC DS0 Control
TDC2
Register 2
Not used
(set to 00H)
Not used
(set to 00H)
Not used
(set to 00H)
Not used
(set to 00H)
NOTES:
1. Test Registers 1, 2, and 3 are used only by the factory; these registers must be cleared (set to all
zeros) on power– up initialization to insure proper operation.
2. Register banks CxH, DxH, ExH, and FxH are not accessible.
31 of 110
DS21FT44/DS21FF44
9. PARALLEL PORT
The DS21Q44 is controlled via either a non–multiplexed (MUX = 0) or a multiplexed (MUX = 1) bus by
an external microcontroller or microprocessor. The DS21Q44 can operate with either Intel or Motorola
bus timing configurations. If the BTS pin is tied low, Intel timing will be selected; if tied high, Motorola
timing will be selected. All Motorola bus signals are listed in parenthesis (). See the timing diagrams in
the A.C. Electrical Characteristics in Section 23 for more details.
10.
CONTROL, ID AND TEST REGISTERS
The operation of each framer within the DS21Q44 is configured via a set of ten control registers.
Typically, the control registers are only accessed when the system is first powered up. Once a channel in
the DS21Q44 has been initialized, the control registers will only need to be accessed when there is a
change in the system configuration. There are two Receive Control Register (RCR1 and RCR2), two
Transmit Control Registers (TCR1 and TCR2), and six Common Control Registers (CCR1 to CCR6).
Each of the ten registers are described in this section.
There is a device Identification Register (IDR) at address 0Fh. The MSB of this read–only register is
fixed to a one indicating that the DS21Q44 is present. The T1 pin–for–pin compatible version of the
DS21Q44 is the DS21Q42 and it also has an ID register at address 0Fh and the user can read the MSB to
determine which chip is present since in the DS21Q42 the MSB will be set to a zero and in the DS21Q44
it will be set to a one. The lower 4 bits of the IDR are used to display the die revision of the chip.
Power–Up Sequence
The DS21Q44 does not automatically clear its register space on power–up. After the supplies are stable,
each of the four framer’s register space should be configured for operation by writing to all of the internal
registers. This includes setting the Test and all unused registers to 00Hex.
This can be accomplished using a two-pass approach on each framer within the DS21Q44.
1. Clear framer’s register space by writing 00H to the addresses 00H through 0BFH.
2. Program required registers to achieve desired operating mode.
Note:
When emulating the DS21Q43 feature set (FMS = 1), the full address space (00H through 0BFH) must be
initialized. DS21Q43 emulation require address pin A7 to be used. FMS is tied to ground for the
DS21FF44/DS21FT44.
Finally, after the TSYSCLK and RSYSCLK inputs are stable, the ESR bit should be toggled from a zero
to a one (this step can be skipped if the elastic stores are disabled).
32 of 110
DS21FT44/DS21FF44
IDR: DEVICE IDENTIFICATION REGISTER (Address=0F Hex)
(MSB)
T1E1
0
0
SYMBOL
POSITION
T1E1
IDR.7
ID3
IDR.3
ID2
ID1
ID0
IDR.1
IDR.2
IDR.0
0
ID3
ID2
ID1
(LSB)
ID0
NAME AND DESCRIPTION
T1 or E1 Chip Determination Bit.
0=T1 chip
1=E1 chip
Chip Revision Bit 3. MSB of a decimal code that represents
the chip revision.
Chip Revision Bit 2.
Chip Revision Bit 1.
Chip Revision Bit 0. LSB of a decimal code that represents
the chip revision.
RCR1: RECEIVE CONTROL REGISTER 1 (Address=10 Hex)
(MSB)
RSMF
RSM
RSIO
SYMBOL
POSITION
RSMF
RCR1.7
RSM
RCR1.6
RSIO
RCR1.5
–
–
FRC
RCR1.4
RCR1.3
RCR1.2
SYNCE
RCR1.1
RESYNC
RCR1.0
–
–
FRC
SYNCE
(LSB)
RESYNC
NAME AND DESCRIPTION
RSYNC Multiframe Function. Only used if the RSYNC
pin is programmed in the multiframe mode (RCR1.6=1).
0 = RSYNC outputs CAS multiframe boundaries
1 = RSYNC outputs CRC4 multiframe boundaries
RSYNC Mode Select.
0 = frame mode (see the timing in Section 22)
1 = multiframe mode (see the timing in Section 22)
RSYNC I/O Select. (note: this bit must be set to zero when
RCR2.1=0).
0 = RSYNC is an output (depends on RCR1.6)
1 = RSYNC is an input (only valid if elastic store enabled)
Not Assigned. Should be set to zero when written.
Not Assigned. Should be set to zero when written.
Frame Resync Criteria.
0 = resync if FAS received in error 3 consecutive times
1 = resync if FAS or bit 2 of non–FAS is received in error 3
consecutive times
Sync Enable.
0 = auto resync enabled
1 = auto resync disabled
Resync. When toggled from low to high, a resync is
initiated. Must be cleared and set again for a subsequent
resync.
33 of 110
DS21FT44/DS21FF44
SYNC/RESYNC CRITERIA Table 10–1
FRAME OR
MULTIFRAME
LEVEL
FAS
CRC4
SYNC CRITERIA
RESYNC CRITERIA
ITU SPEC.
FAS present in frame N
and N + 2, and FAS not
present in frame N + 1
Three consecutive
incorrect FAS received
G.706
4.1.1
4.1.2
Two valid MF
alignment words found
within 8 ms
Valid MF alignment
word found and
previous timeslot 16
contains code other than
all zeros
CAS
Alternate (RCR1.2=1)
the above criteria is met
or three consecutive
incorrect bit 2 of non–
FAS received
915 or more CRC4 code
words out of 1000
received in error
Two consecutive MF
alignment words
received in error
G.706
4.2 and 4.3.2
G.732 5.2
RCR2: RECEIVE CONTROL REGISTER 2 (Address=11 Hex)
(MSB)
Sa8S
Sa7S
Sa6S
SYMBOL
POSITION
Sa8S
RCR2.7
Sa7S
RCR2.6
Sa6S
RCR2.5
Sa5S
RCR2.4
Sa4S
RCR2.3
RBCS
RCR2.2
RESE
RCR2.1
–
RCR2.0
Sa5S
Sa4S
RBCS
RESE
(LSB)
–
NAME AND DESCRIPTION
Sa8 Bit Select. Set to one to have RLCLK pulse at the Sa8
bit position; set to zero to force RLCLK low during Sa8 bit
position. See Section 22 for timing details.
Sa7 Bit Select. Set to one to have RLCLK pulse at the Sa7
bit position; set to zero to force RLCLK low during Sa7 bit
position. See Section 22 for timing details.
Sa6 Bit Select. Set to one to have RLCLK pulse at the Sa6
bit position; set to zero to force RLCLK low during Sa6 bit
position. See Section 22 for timing details.
Sa5 Bit Select. Set to one to have RLCLK pulse at the Sa5
bit position; set to zero to force RLCLK low during Sa5 bit
position. See Section 22 for timing details.
Sa4 Bit Select. Set to one to have RLCLK pulse at the Sa4
bit position; set to zero to force RLCLK low during Sa4 bit
position. See Section 22 for timing details.
Receive Side Backplane Clock Select.
0 = if RSYSCLK is 1.544 MHz
1 = if RSYSCLK is 2.048 MHz
Receive Side Elastic Store Enable.
0 = elastic store is bypassed
1 = elastic store is enabled
Not Assigned. Should be set to zero when written.
34 of 110
DS21FT44/DS21FF44
TCR1: TRANSMIT CONTROL REGISTER 1 (Address=12 Hex)
(MSB)
ODF
TFPT
T16S
SYMBOL
POSITION
ODF
TCR1.7
TFPT
TCR1.6
T16S
TCR1.5
TUA1
TCR1.4
TSiS
TCR1.3
TSA1
TCR1.2
TSM
CR1.1
TSIO
TCR1.0
TUA1
TSiS
TSA1
TSM
(LSB)
TSIO
NAME AND DESCRIPTION
Output Data Format.
0 = bipolar data at TPOS and TNEG
1 = NRZ data at TPOS; TNEG=0
Transmit Timeslot 0 Pass Through.
0 = FAS bits/Sa bits/Remote Alarm sourced internally from
the TAF and TNAF registers
1 = FAS bits/Sa bits/Remote Alarm sourced from TSER
Transmit Timeslot 16 Data Select.
0 = sample timeslot 16 at TSER pin
1 = source timeslot 16 from TS0 to TS15 registers
Transmit Unframed All Ones.
0 = transmit data normally
1 = transmit an unframed all one’s code at TPOS and TNEG
Transmit International Bit Select.
0 = sample Si bits at TSER pin
1 = source Si bits from TAF and TNAF registers (in this
mode, TCR1.6 must be set to 0)
Transmit Signaling All Ones.
0 = normal operation
1 = force timeslot 16 in every frame to all ones
TSYNC Mode Select.
0 = frame mode (see the timing in Section 22)
1 = CAS and CRC4 multiframe mode (see the timing in
Section 22)
TSYNC I/O Select.
0 = TSYNC is an input
1 = TSYNC is an output
NOTE:
See Figure 22–15 for more details about how the Transmit Control Registers affect the operation of the
DS21Q44.
TCR2: TRANSMIT CONTROL REGISTER 2 (Address=13 Hex)
(MSB)
Sa8S
Sa7S
Sa6S
SYMBOL
POSITION
Sa8S
TCR2.7
Sa5S
Sa4S
ODM
AEBE
(LSB)
PF
NAME AND DESCRIPTION
Sa8 Bit Select. Set to one to source the Sa8 bit from the
TLINK pin; set to zero to not source the Sa8 bit. See Section
22 for timing details.
35 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
Sa7S
TCR2.6
Sa6S
TCR2.5
Sa5S
TCR2.4
Sa4S
TCR2.3
ODM
TCR2.2
AEBE
TCR2.1
PF
TCR2.0
NAME AND DESCRIPTION
Sa7 Bit Select. Set to one to source the Sa7 bit from the
TLINK pin; set to zero to not source the Sa7 bit. See Section
22 for timing details.
Sa6 Bit Select. Set to one to source the Sa6 bit from the
TLINK pin; set to zero to not source the Sa6 bit. See Section
22 for timing details.
Sa5 Bit Select. Set to one to source the Sa5 bit from the
TLINK pin; set to zero to not source the Sa5 bit. See Section
22 for timing details.
Sa4 Bit Select. Set to one to source the Sa4 bit from the
TLINK pin; set to zero to not source the Sa4 bit. See Section
22 for timing details.
Output Data Mode.
0 = pulses at TPOSO and TNEGO are one full TCLKO
period wide
1 = pulses at TPOSO and TNEGO are 1/2 TCLKO period
wide
Automatic E–Bit Enable.
0 = E–bits not automatically set in the transmit direction
1 = E–bits automatically set in the transmit direction
Function of RLOS/LOTC Pin.
0 = Receive Loss of Sync (RLOS)
1 = Loss of Transmit Clock (LOTC)
CCR1: COMMON CONTROL REGISTER 1 (Address=14 Hex)
(MSB)
FLB
THDB3
TG802
SYMBOL
POSITION
FLB
CCR1.7
THDB3
CCR1.6
TG802
CCR1.5
TCRC4
CCR1.4
RSM
CCR1.3
RHDB3
CCR1.2
TCRC4
RSM
RHDB3
RG802
(LSB)
RCRC4
NAME AND DESCRIPTION
Framer Loopback.
0=loopback disabled
1=loopback enabled
Transmit HDB3 Enable.
0=HDB3 disabled
1=HDB3 enabled
Transmit G.802 Enable. See Section 22 for details.
0=do not force TCHBLK high during bit 1 of timeslot 26
1=force TCHBLK high during bit 1 of timeslot 26
Transmit CRC4 Enable.
0=CRC4 disabled
1=CRC4 enabled
Receive Signaling Mode Select.
0=CAS signaling mode
1=CCS signaling mode
Receive HDB3 Enable.
0=HDB3 disabled
1=HDB3 enabled
36 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
RG802
CCR1.1
RCRC4
CCR1.0
NAME AND DESCRIPTION
Receive G.802 Enable. See Section 22 for details.
0=do not force RCHBLK high during bit 1 of timeslot 26
1=force RCHBLK high during bit 1 of timeslot 26
Receive CRC4 Enable.
0=CRC4 disabled
1=CRC4 enabled
FRAMER LOOPBACK
When CCR1.7 is set to a one, the framer will enter a Framer LoopBack (FLB) mode. See Figure 6–1 for
more details. This loopback is useful in testing and debugging applications. In FLB, the framer will
loop data from the transmit side back to the receive side. When FLB is enabled, the following will occur:
1. Data will be transmitted as normal at TPOS and TNEG.
2. Data input via RPOS and RNEG will be ignored.
3. The RCLK output will be replaced with the TCLK input.
CCR2: COMMON CONTROL REGISTER 2 (Address=1A Hex)
(MSB)
ECUS
VCRFS
AAIS
SYMBOL
POSITION
ECUS
CCR2.7
VCRFS
CCR2.6
AAIS
CCR2.5
ARA
CCR2.4
RSERC
CCR2.3
LOTCMC
CCR2.2
RFF
CCR2.1
ARA
RSERC
LOTCMC
RFF
(LSB)
RFE
NAME AND DESCRIPTION
Error Counter Update Select. See Section 12 for details.
0=update error counters once a second
1=update error counters every 62.5 ms (500 frames)
VCR Function Select. See Section 12 for details.
0=count BiPolar Violations (BPVs)
1=count Code Violations (CVs)
Automatic AIS Generation.
0=disabled
1=enabled
Automatic Remote Alarm Generation.
0=disabled
1=enabled
RSER Control.
0=allow RSER to output data as received under all conditions
1=force RSER to one under loss of frame alignment conditions
Loss of Transmit Clock Mux Control. Determines whether
the transmit side formatter should switch to the ever present
RCLK if the TCLK should fail to transition (see Figure 6–1).
0=do not switch to RCLK if TCLK stops
1=switch to RCLK if TCLK stops
Receive Force Freeze. Freezes receive side signaling at RSIG
(and RSER if CCR3.3=1); will override Receive Freeze Enable
(RFE). See Section 14 or details.
0=do not force a freeze event
1=force a freeze event
37 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
RFE
CCR2.0
NAME AND DESCRIPTION
Receive Freeze Enable. See Section 14 for details.
0=no freezing of receive signaling data will occur
1=allow freezing of receive signaling data at RSIG (and RSER
if CCR3.3=1).
AUTOMATIC ALARM GENERATION
The DS21Q44 can be programmed to automatically transmit AIS or Remote Alarm. When automatic
AIS generation is enabled (CCR2.5 = 1), the framer monitors the receive side to determine if any of the
following conditions are present: loss of receive frame synchronization, AIS alarm (all one’s) reception,
or loss of receive carrier (or signal). If any one (or more) of the above conditions is present, then the
framer will transmit an AIS alarm.
When automatic RAI generation is enabled (CCR2.4 = 1), the framer monitors the receive side to
determine if any of the following conditions are present: loss of receive frame synchronization, AIS alarm
(all one’s) reception, loss of receive carrier or if CRC4 multiframe synchronization (if enabled) cannot be
found within 128 ms of FAS synchronization. If any one (or more) of the above conditions is present,
then the framer will transmit a RAI alarm. RAI generation conforms to ETS 300 011 specifications and a
constant Remote Alarm will be transmitted if the framer cannot find CRC4 multiframe synchronization
within 400 ms as per G.706.
It is an illegal state to have both CCR2.4 and CCR2.5 set to one at the same time.
CCR3: COMMON CONTROL REGISTER 3 (Address=1B Hex)
(MSB)
TESE
TCBFS
TIRFS
SYMBOL
POSITION
TESE
CCR3.7
TCBFS
CCR3.6
TIRFS
CCR3.5
–
RSRE
CCR3.4
CCR3.3
–
RSRE
THSE
TBCS
(LSB)
RCLA
NAME AND DESCRIPTION
Transmit Side Elastic Store Enable.
0=elastic store is bypassed
1=elastic store is enabled
Transmit Channel Blocking Registers (TCBR) Function
Select.
0=TCBRs define the operation of the TCHBLK output pin
1=TCBRs define which signaling bits are to be inserted
Transmit Idle Registers (TIR) Function Select. See Section
15 for details.
0=TIRs define in which channels to insert idle code
1=TIRs define in which channels to insert data from RSER
(i.e., Per Channel Loopback function)
Not Assigned. Should be set to zero when written.
Receive Side Signaling Re–Insertion Enable. See Section 14
for details.
0=do not re–insert signaling bits into the data stream presented
at the RSER pin
1=re–insert the signaling bits into data stream presented at the
RSER pin
38 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
THSE
CCR3.2
TBCS
CCR3.1
RCLA
CCR3.0
NAME AND DESCRIPTION
Transmit Side Hardware Signaling Insertion Enable. See
Section 14 for details.
0=do not insert signaling from the TSIG pin into the data
stream presented at the TSER pin
1=insert signaling from the TSIG pin into the data stream
presented at the TSER pin
Transmit Side Backplane Clock Select.
0=if TSYSCLK is 1.544 MHz
1=if TSYSCLK is 2.048 MHz
Receive Carrier Loss (RCL) Alternate Criteria.
0=RCL declared upon 255 consecutive zeros (125 us)
1=RCL declared upon 2048 consecutive zeros (1 ms)
CCR4: COMMON CONTROL REGISTER 4 (Address=A8 Hex)
(MSB)
RLB
–
–
SYMBOL
POSITION
RLB
CCR4.7
–
–
TCM4
CCR4.6
CCR4.5
CCR4.4
TCM3
TCM2
TCM1
TCM0
CCR4.3
CCR4.2
CCR4.1
CCR4.0
TCM4
TCM3
TCM2
TCM1
(LSB)
TCM0
NAME AND DESCRIPTION
Remote Loopback.
0 = loopback disabled
1 = loopback enabled
Not Assigned. Should be set to zero when written.
Not Assigned. Should be set to zero when written.
Transmit Channel Monitor Bit 4. MSB of a channel decode
that deter-mines which transmit channel data will appear in the
TDS0M register. See Section 13 or details.
Transmit Channel Monitor Bit 3.
Transmit Channel Monitor Bit 2.
Transmit Channel Monitor Bit 1.
Transmit Channel Monitor Bit 0. LSB of the channel
decode.
CCR5: COMMON CONTROL REGISTER 5 (Address = AA Hex)
(MSB)
–
RESALGN TESALGN
SYMBOL
POSITION
–
RESALGN
CCR5.7
CCR5.6
RCM4
RCM3
RCM2
RCM1
(LSB)
RCM0
NAME AND DESCRIPTION
Not Assigned. Should be set to zero when written
Receive Elastic Store Align. Setting this bit from a zero to a
one may force the receive elastic store’s write/read pointers to
a minimum separation of half a frame. No action will be taken
if the pointer separation is already greater or equal to half a
frame. If pointer separation is less then half a frame, the
command will be executed and data will be disrupted. Should
be toggled after RSYSCLK has been applied and is stable.
39 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
TESALGN
CCR5.5
RCM4
CCR5.4
RCM3
RCM2
RCM1
RCM0
CCR5.3
CCR5.2
CCR5.1
CCR5.0
NAME AND DESCRIPTION
Must be cleared and set again for a subsequent align. See
Section 17 for details.
Transmit Elastic Store Align. Setting this bit from a zero to
a one may force the transmit elastic store’s write/read pointers
to a minimum separation of half a frame. No action will be
taken if the pointer separation is already greater or equal to
half a frame. If pointer separation is less then half a frame, the
command will be executed and data will be disrupted. Should
be toggled after TSYSCLK has been applied and is stable.
Must be cleared and set again for a subsequent align. See
Section 17 for details.
Receive Channel Monitor Bit 4. MSB of a channel decode
that determines which receive channel data will appear in the
RDS0M register. See Section 13 for details.
Receive Channel Monitor Bit 3.
Receive Channel Monitor Bit 2.
Receive Channel Monitor Bit 1.
Receive Channel Monitor Bit 0. LSB of the channel decode.
CCR6: COMMON CONTROL REGISTER 6 (Address=1D Hex)
(MSB)
–
–
–
SYMBOL
POSITION
–
–
–
–
–
TCLKSRC
CCR6.7
CCR6.6
CCR6.5
CCR6.4
CCR6.3
CCR6.2
RESR
CCR6.1
TESR
CCR6.0
–
–
TCLKSRC
RESR
(LSB)
TESR
NAME AND DESCRIPTION
Not Assigned. Should be set to zero when written
Not Assigned. Should be set to zero when written
Not Assigned. Should be set to zero when written
Not Assigned. Should be set to zero when written
Not Assigned. Should be set to zero when written
Transmit Clock Source Select. This function allows the user
to internally select RCLK as the clock source for the transmit
side formatter.
0 = Transmit side formatter clocked with signal applied at
TCLK pin. LOTC Mux function is operational (TCR1.7)
1 = Transmit side formatter clocked with RCLK.
Receive Elastic Store Reset. Setting this bit from a zero to a
one will force the receive elastic store to a depth of one frame.
Receive data is lost during the reset. Should be toggled after
RSYSCLK has been applied and is stable. Do not leave this
bit set high.
Transmit Elastic Store Reset. Setting this bit from a zero to
a one will force the transmit elastic store to a depth of one
frame. Transmit data is lost during the reset. Should be
toggled after TSYSCLK has been applied and is stable. Do
not leave this bit set high.
40 of 110
DS21FT44/DS21FF44
11.
STATUS AND INFORMATION REGISTERS
There is a set of seven registers per framer that contain information on the current real time status of a
framer in the DS21Q44, Status Register 1 (SR1), Status Register 2 (SR2), Receive Information Register
(RIR), Synchronizer status Register (SSR) and a set of three registers for the onboard HDLC controller.
The specific details on the four registers pertaining to the HDLC controller are covered in Section 19 but
they operate the same as the other status registers in the DS21Q44 and this operation is described below.
When a particular event has occurred (or is occurring), the appropriate bit in one of these four registers
will be set to a one. All of the bits in SR1, SR2, and RIR1 registers operate in a latched fashion. The
Synchronizer status Register contents are not latched. This means that if an event or an alarm occurs and
a bit is set to a one in any of the registers, it will remain set until the user reads that bit. The bit will be
cleared when it is read and it will not be set again until the event has occurred again (or in the case of the
RSA1, RSA0, RDMA, RUA1, RRA, RCL, and RLOS alarms, the bit will remain set if the alarm is still
present).
The user will always precede a read of any of the SR1, SR2 and RIR registers with a write. The byte
written to the register will inform the framer which bits the user wishes to read and have cleared. The
user will write a byte to one of these registers, with a one in the bit positions he or she wishes to read and
a zero in the bit positions he or she does not wish to obtain the latest information on. When a one is
written to a bit location, the read register will be updated with the latest information. When a zero is
written to a bit position, the read register will not be updated and the previous value will be held. A write
to the status and information registers will be immediately followed by a read of the same register. The
read result should be logically AND’ed with the mask byte that was just written and this value should be
written back into the same register to insure that bit does indeed clear. This second write step is
necessary because the alarms and events in the status registers occur asynchronously in respect to their
access via the parallel port. This write–read– write scheme allows an external microcontroller or
microprocessor to individually poll certain bits without disturbing the other bits in the register. This
operation is key in controlling the DS21Q44 with higher–order software languages.
The SSR register operates differently than the other three. It is a read only register and it reports the
status of the synchronizer in real time. This register is not latched and it is not necessary to precede a
read of this register with a write.
The SR1, SR2, and HSR registers have the unique ability to initiate a hardware interrupt via the INT*
output pin. Each of the alarms and events in the SR1, SR2, and HSR can be either masked or unmasked
from the interrupt pin via the Interrupt Mask Register 1 (IMR1), Interrupt Mask Register 2 (IMR2), and
HDLC Interrupt Mask Register (HIMR) respectively. The HIMR register is covered in Section 19.
The interrupts caused by four of the alarms in SR1 (namely RUA1, RRA, RCL, and RLOS) act
differently than the interrupts caused by other alarms and events in SR1 and SR2 (namely RSA1, RDMA,
RSA0, RSLIP, RMF, RAF, TMF, SEC, TAF, LOTC, RCMF, and TSLIP). These four alarm interrupts
will force the INT* pin low whenever the alarm changes state (i.e., the alarm goes active or inactive
according to the set/clear criteria in Table 11-1). The INT* pin will be allowed to return high (if no other
interrupts are present) when the user reads the alarm bit that caused the interrupt to occur. If the alarm is
still present, the register bit will remain set.
The event caused interrupts will force the INT* pin low when the event occurs. The INT* pin will be
allowed to return high (if no other interrupts are present) when the user reads the event bit that caused the
interrupt to occur.
41 of 110
DS21FT44/DS21FF44
ISR: INTERRUPT STATUS REGISTER
(Any address from 0C0 Hex to 0FF Hex)
(MSB)
F3HDLC
F3SR
F2HDLC
F2SR
SYMBOL
POSITION
F3HDLC
ISR.7
F3SR
ISR.6
F2HDLC
ISR.5
F2SR
ISR.4
F1HDLC
ISR.3
F1SR
ISR.2
F0HDLC
ISR.1
F0SR
ISR.0
F1HDLC
F1SR
F0HDLC
NAME AND DESCRIPTION
FRAMER 3 HDLC CONTROLLER INTERRUPT
REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 3 SR1 or SR2 INTERRUPT REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 2 HDLC CONTROLLER INTERRUPT
REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 2 SR1 or SR2 INTERRUPT REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 1 HDLC CONTROLLER INTERRUPT
REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 1 SR1 or SR2 INTERRUPT REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 0 HDLC CONTROLLER INTERRUPT
REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
FRAMER 0 SR1 or SR2 INTERRUPT REQUEST.
0 = No interrupt request pending.
1 = Interrupt request pending.
42 of 110
(LSB)
F0SR
DS21FT44/DS21FF44
RIR: RECEIVE INFORMATION REGISTER (Address=08 Hex)
(MSB)
TESF
TESE
LORC
SYMBOL
POSITION
TESF
RIR.7
TESE
RIR.6
LORC
RIR.5
RESF
RIR.4
RESE
RIR.3
CRCRC
RIR.2
FASRC
RIR.1
CASRC
RIR.0
RESF
RESE
CRCRC
FASRC
(LSB)
CASRC
NAME AND DESCRIPTION
Transmit Side Elastic Store Full. Set when the transmit side
elastic store buffer fills and a frame is deleted.
Transmit Side Elastic Store Empty. Set when the transmit
side elastic store buffer empties and a frame is repeated.
Loss of Receive Clock. Set when the RCLK pin has not
transitioned for at least 2ms (3ms ± 1ms).
Receive Side Elastic Store Full. Set when the receive side
elastic store buffer fills and a frame is deleted.
Receive Side Elastic Store Empty. Set when the receive side
elastic store buffer empties and a frame is repeated.
CRC Resync Criteria Met. Set when 915/1000 code words
are received in error.
FAS Resync Criteria Met. Set when 3 consecutive FAS
words are received in error.
CAS Resync Criteria Met. Set when 2 consecutive CAS MF
alignment words are received in error.
SSR: SYNCHRONIZER STATUS REGISTER (Address=1E Hex)
(MSB)
CSC5
CSC4
CSC3
SYMBOL
POSITION
CSC5
CSC4
CSC3
CSC2
CSC0
SSR.7
SSR.6
SSR.5
SSR.4
SSR.3
FASSA
SSR.2
CASSA
SSR.1
CRC4SA
SSR.0
CSC2
CSC0
FASSA
CASSA
(LSB)
CRC4SA
NAME AND DESCRIPTION
CRC4 Sync Counter Bit 5. MSB of the 6–bit counter.
CRC4 Sync Counter Bit 4.
CRC4 Sync Counter Bit 3.
CRC4 Sync Counter Bit 2.
CRC4 Sync Counter Bit 0. LSB of the 6–bit counter. The
next to LSB is not accessible.
FAS Sync Active. Set while the synchronizer is searching for
alignment at the FAS level.
CAS MF Sync Active. Set while the synchronizer is
searching for the CAS MF alignment word.
CRC4 MF Sync Active. Set while the synchronizer is
searching for the CRC4 MF alignment word.
CRC4 SYNC COUNTER
The CRC4 Sync Counter increments each time the 8 ms CRC4 multiframe search times out. The counter
is cleared when the framer has successfully obtained synchronization at the CRC4 level. The counter can
also be cleared by disabling the CRC4 mode (CCR1.0=0). This counter is useful for determining the
amount of time the framer has been searching for synchronization at the CRC4 level. ITU G.706
suggests that if synchronization at the CRC4 level cannot be obtained within 400 ms, then the search
should be abandoned and proper action taken. The CRC4 Sync Counter will rollover.
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DS21FT44/DS21FF44
SR1: STATUS REGISTER 1 (Address=06 Hex)
(MSB)
RSA1
RDMA
RSA0
SYMBOL
POSITION
RSA1
SR1.7
RDMA
SR1.6
RSA0
SR1.5
RSLIP
SR1.4
RUA1
SR1.3
RRA
SR1.2
RCL
SR1.1
RLOS
SR1.0
RSLIP
RUA1
RRA
RCL
(LSB)
RLOS
NAME AND DESCRIPTION
Receive Signaling All Ones / Signaling Change. Set when
over a full MF, the content of timeslot 16 contains less than
three zeros. This alarm is not disabled in the CCS signaling
mode. A change in the contents of RS1 through RS16 from
one multiframe to the next will cause RSA1 and RSA0 to be
set.
Receive Distant MF Alarm. Set when bit–6 of timeslot 16 in
frame 0 has been set for two consecutive multiframes. This
alarm is not disabled in the CCS signaling mode.
Receive Signaling All Zeros / Signaling Change. Set when
over a full MF, timeslot 16 contains all zeros. A change in the
contents of RS1 through RS16 from one multiframe to the next
will cause RSA1 and RSA0 to be set.
Receive Side Elastic Store Slip. Set when the elastic store
has either repeated or deleted a frame of data.
Receive Unframed All Ones. Set when an unframed all ones
code is received at RPOS and RNEG.
Receive Remote Alarm. Set when a remote alarm is received
at RPOS and RNEG.
Receive Carrier Loss. Set when 255 (or 2048 if CCR3.0=1)
consecutive zeros have been detected at RPOS and RNEG.
Receive Loss of Sync. Set when the device is not
synchronized to the receive E1 stream.
44 of 110
DS21FT44/DS21FF44
ALARM CRITERIA Table 11-1
ALARM
SET CRITERIA
CLEAR CRITERIA
RSA1 (receive signaling over 16 consecutive frames
all ones)
(one full MF) timeslot 16
contains less than three
zeros
RSA0 (receive signaling over 16 consecutive frames
all zeros)
(one full MF) timeslot 16
contains all zeros
RDMA (receive distant
multiframe alarm)
RUA1 (receive
unframed all ones)
RRA (receive remote
alarm)
RCL (receive carrier
loss)
over 16 consecutive frames
(one full MF) timeslot 16
contains three or more
zeros
over 16 consecutive frames
(one full MF) timeslot 16
contains at least a single
one
bit 6 in timeslot 16 of
bit 6 in timeslot 16 of
frame 0 set to one for two
frame 0 set to zero for two
consecutive MF
consecutive MF
less than three zeros in two more than two zeros in two
frames (512 bits)
frames (512 bits)
bit 3 of non–align frame set bit 3 of non–align frame set
to one for three consecutive to zero for three
occasions
consecutive occasions
255 (or 2048) consecutive
in 255 bit times, at least 32
zeros received
ones are received
ITU
SPEC.
G.732
4.2
G.732
5.2
O.162
2.1.5
O.162
1.6.1.2
O.162
2.1.4
G.775 / G.962
SR2: STATUS REGISTER 2 (Address=07 Hex)
(MSB)
RMF
RAF
TMF
SYMBOL
POSITION
RMF
SR2.7
RAF
SR2.6
TMF
SR2.5
SEC
SR2.4
TAF
SR2.3
LOTC
SR2.2
SEC
TAF
LOTC
RCMF
(LSB)
TSLIP
NAME AND DESCRIPTION
Receive CAS Multiframe. Set every 2 ms (regardless if CAS
signaling is enabled or not) on receive multiframe boundaries.
Used to alert the host that signaling data is available.
Receive Align Frame. Set every 250 s at the beginning of
align frames. Used to alert the host that Si and Sa bits are
available in the RAF and RNAF registers.
Transmit Multiframe. Set every 2 ms (regardless if CRC4 is
enabled) on transmit multiframe boundaries. Used to alert the
host that signaling data needs to be updated.
One Second Timer. Set on increments of one second based
on RCLK. If CCR2.7=1, then this bit will be set every 62.5
ms instead of once a second.
Transmit Align Frame. Set every 250 s at the beginning of
align frames. Used to alert the host that the TAF and TNAF
registers need to be updated.
Loss of Transmit Clock. Set when the TCLK pin has not
transitioned for one channel time (or 3.9 s). Will force the
LOTC pin high if enabled via TCR2.0.
45 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
RCMF
SR2.1
TSLIP
SR2.0
NAME AND DESCRIPTION
Receive CRC4 Multiframe. Set on CRC4 multiframe
boundaries; will continue to be set every 2 ms on an arbitrary
boundary if CRC4 is disabled.
Transmit Elastic Store Slip. Set when the elastic store has
either repeated or deleted a frame of data.
IMR1: INTERRUPT MASK REGISTER 1 (Address=16 Hex)
(MSB)
RSA1
RDMA
RSA0
SYMBOL
POSITION
RSA1
IMR1.7
RDMA
IMR1.6
RSA0
IMR1.5
RSLIP
IMR1.4
RUA1
IMR1.3
RRA
IMR1.2
RCL
IMR1.1
RLOS
IMR1.0
RSLIP
RUA1
RRA
RCL
NAME AND DESCRIPTION
Receive Signaling All Ones / Signaling Change.
0=interrupt masked
1=interrupt enabled
Receive Distant MF Alarm.
0=interrupt masked
1=interrupt enabled
Receive Signaling All Zeros / Signaling Change.
0=interrupt masked
1=interrupt enabled
Receive Elastic Store Slip Occurrence.
0=interrupt masked
1=interrupt enabled
Receive Unframed All Ones.
0=interrupt masked
1=interrupt enabled
Receive Remote Alarm.
0=interrupt masked
1=interrupt enabled
Receive Carrier Loss.
0=interrupt masked
1=interrupt enabled
Receive Loss of Sync.
0=interrupt masked
1=interrupt enabled
46 of 110
(LSB)
RLOS
DS21FT44/DS21FF44
IMR2: INTERRUPT MASK REGISTER 2 (Address=17 Hex)
(MSB)
RMF
RAF
TMF
SYMBOL
POSITION
RMF
IMR2.7
RAF
IMR2.6
TMF
IMR2.5
SEC
IMR2.4
TAF
IMR2.3
LOTC
IMR2.2
RCMF
IMR2.1
TSLIP
IMR2.0
12.
SEC
TAF
LOTC
RCMF
(LSB)
TSLIP
NAME AND DESCRIPTION
Receive CAS Multiframe.
0=interrupt masked
1=interrupt enabled
Receive Align Frame.
0=interrupt masked
1=interrupt enabled
Transmit Multiframe.
0=interrupt masked
1=interrupt enabled
One Second Timer.
0=interrupt masked
1=interrupt enabled
Transmit Align Frame.
0=interrupt masked
1=interrupt enabled
Loss Of Transmit Clock.
0=interrupt masked
1=interrupt enabled
Receive CRC4 Multiframe.
0=interrupt masked
1=interrupt enabled
Transmit Side Elastic Store Slip Occurrence.
0=interrupt masked
1=interrupt enabled
ERROR COUNT REGISTERS
There are a set of four counters in each framer that record bipolar or code violations, errors in the CRC4
SMF code words, E bits as reported by the far end, and word errors in the FAS. Each of these four
counters are automatically updated on either one second boundaries (CCR2.7=0) or every 62.5 ms
(CCR2.7=1) as determined by the timer in Status Register 2 (SR2.4). Hence, these registers contain
performance data from either the previous second or the previous 62.5 ms. The user can use the interrupt
from the one second timer to determine when to read these registers. The user has a full second (or 62.5
ms) to read the counters before the data is lost. All four counters will saturate at their respective
maximum counts and they will not rollover.
BPV or Code Violation Counter
Violation Count Register 1 (VCR1) is the most significant word and VCR2 is the least significant word of
a 16–bit counter that records either BiPolar Violations (BPVs) or Code Violations (CVs). If CCR2.6=0,
then the VCR counts bipolar violations. Bipolar violations are defined as consecutive marks of the same
polarity. In this mode, if the HDB3 mode is set for the receive side via CCR1.2, then HDB3 code words
are not counted as BPVs. If CCR2.6=1, then the VCR counts code violations as defined in ITU O.161.
Code violations are defined as consecutive bipolar violations of the same polarity. In most applications,
the framer should be programmed to count BPVs when receiving AMI code and to count CVs when
47 of 110
DS21FT44/DS21FF44
receiving HDB3 code. This counter increments at all times and is not disabled by loss of sync conditions.
The counter saturates at 65,535 and will not rollover. The bit error rate on a E1 line would have to be
greater than 10** –2 before the VCR would saturate.
VCR1: UPPER BIPOLAR VIOLATION COUNT REGISTER 1 (Address=00 Hex)
VCR2: LOWER BIPOLAR VIOLATION COUNT REGISTER 2 (Address=01 Hex)
(MSB)
V15
V7
V14
V6
V13
V5
SYMBOL
POSITION
V15
V0
VCR1.7
VCR2.0
V12
V4
V11
V3
V10
V2
(LSB)
V8
V0
V9
V1
VCR1
VCR2
NAME AND DESCRIPTION
MSB of the 16–bit code violation count
LSB of the 10–bit code violation count
CRC4 Error Counter
CRC4 Count Register 1 (CRCCR1) is the most significant word and CRCCR2 is the least significant
word of a 10–bit counter that records word errors in the Cyclic Redundancy Check 4 (CRC4). Since the
maximum CRC4 count in a one second period is 1000, this counter cannot saturate. The counter is
disabled during loss of sync at either the FAS or CRC4 level; it will continue to count if loss of
multiframe sync occurs at the CAS level.
CRCCR1: CRC4 COUNT REGISTER 1 (Address=02 Hex)
CRCCR2: CRC4 COUNT REGISTER 2 (Address=03 Hex)
(MSB)
(note 1)
CRC7
(note 1)
CRC6
(note 1)
CRC5
(note 1)
CRC4
(note 1)
CRC3
(note 1)
CRC2
CRC9
CRC1
SYMBOL
POSITION
NAME AND DESCRIPTION
CRC9
CRC0
CRCCR1.1
CRCCR2.0
MSB of the 10–Bit CRC4 error count
LSB of the 10–Bit CRC4 error count
(LSB)
CRC8
CRC0
CRCCR1
CRCCR2
NOTE:
1. The upper 6 bits of CRCCR1 at address 02 are the most significant bits of the 12–bit FAS error
counter.
E–Bit Counter
E–bit Count Register 1 (EBCR1) is the most significant word and EBCR2 is the least significant word of
a 10–bit counter that records Far End Block Errors (FEBE) as reported in the first bit of frames 13 and 15
on E1 lines running with CRC4 multiframe. These count registers will increment once each time the
received E–bit is set to zero. Since the maximum E–bit count in a one second period is 1000, this counter
cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC4 level; it will
continue to count if loss of multiframe sync occurs at the CAS level.
48 of 110
DS21FT44/DS21FF44
EBCR1: E–BIT COUNT REGISTER 1 (Address=04 Hex)
EBCR2: E–BIT COUNT REGISTER 2 (Address=05 Hex)
(MSB)
(note 1)
EB7
(note 1)
EB6
(note 1)
EB5
SYMBOL
POSITION
EB9
EB0
EBCR1.1
EBCR2.0
(note 1)
EB4
(note 1)
EB3
(note 1)
EB2
EB9
EB1
(LSB)
EB8
EB0
EBCR1
EBCR2
NAME AND DESCRIPTION
MSB of the 10–Bit E–Bit Error Count
LSB of the 10–Bit E–Bit Error Count
NOTE:
The upper 6 bits of EBCR1 at address 04 are the least significant bits of the 12–bit FAS error counter.
FAS Error Counter
FAS Count Register 1 (FASCR1) is the most significant word and FASCR2 is the least significant word
of a 12–bit counter that records word errors in the Frame Alignment Signal in timeslot 0. This counter is
disabled when RLOS is high. FAS errors will not be counted when the framer is searching for FAS
alignment and/or synchronization at either the CAS or CRC4 multiframe level. Since the maximum FAS
word error count in a one second period is 4000, this counter cannot saturate.
FASCR1: FAS ERROR COUNT REGISTER 1 (Address=02 Hex)
FASCR2: FAS ERROR COUNT REGISTER 2 (Address=04 Hex)
(MSB)
FAS11
FAS5
FAS10
FAS4
FAS9
FAS3
FAS8
FAS2
FAS7
FAS1
FAS6
FAS0
(note 2)
(note 1)
SYMBOL
POSITION
NAME AND DESCRIPTION
FAS11
FAS0
FASCR1.7
FASCR2.2
MSB of the 12–Bit FAS Error Count
LSB of the 12–Bit FAS Error Count
(LSB)
(note 2)
(note 1)
FASCR1
FASCR2
NOTES:
1. The lower 2 bits of FASCR1 at address 02 are the most significant bits of the 10–bit CRC4 error
counter.
2. The lower 2 bits of FASCR2 at address 04 are the most significant bits of the 10–bit E–Bit counter.
13.
DS0 MONITORING FUNCTION
Each framer in the DS21Q44 has the ability to monitor one DS0 64 Kbps channel in the transmit
direction and one DS0 channel in the receive direction at the same time. In the transmit direction the user
will determine which channel is to be monitored by properly setting the TCM0 to TCM4 bits in the CCR4
register. In the receive direction, the RCM0 to RCM4 bits in the CCR5 register need to be properly set.
The DS0 channel pointed to by the TCM0 to TCM4 bits will appear in the Transmit DS0 Monitor
(TDS0M) register and the DS0 channel pointed to by the RCM0 to RCM4 bits will appear in the Receive
DS0 (RDS0M) register. The TCM4 to TCM0 and RCM4 to RCM0 bits should be programmed with the
decimal decode of the appropriate E1 channel. Channels 1 through 32 map to register values 0 through
31.
49 of 110
DS21FT44/DS21FF44
For example, if DS0 channel 6 (timeslot 5) in the transmit direction and DS0 channel 15 (timeslot 14) in
the receive direction needed to be monitored, then the following values would be programmed into CCR4
and CCR5:
TCM4 = 0
TCM3 = 0
TCM2 = 1
TCM1 = 0
TCM0 = 1
RCM4 = 0
RCM3 = 1
RCM2 = 1
RCM1 = 1
RCM0 = 0
CCR4: COMMON CONTROL REGISTER 4 (Address=A8 Hex)
[Repeated here from section 10 for convenience]
(MSB)
RLB
–
–
TCM4
SYMBOL
POSITION
RLB
CCR4.7
–
–
TCM4
CCR4.6
CCR4.5
CCR4.4
TCM3
TCM2
TCM1
TCM0
CCR4.3
CCR4.2
CCR4.1
CCR4.0
TCM3
TCM2
TCM1
(LSB)
TCM0
NAME AND DESCRIPTION
Remote Loopback.
0 = loopback disabled
1 = loopback enabled
Not Assigned. Should be set to zero when written.
Not Assigned. Should be set to zero when written.
Transmit Channel Monitor Bit 4. MSB of a channel decode
that deter-mines which transmit channel data will appear in the
TDS0M register. See Section 13 or details.
Transmit Channel Monitor Bit 3.
Transmit Channel Monitor Bit 2.
Transmit Channel Monitor Bit 1.
Transmit Channel Monitor Bit 0. LSB of the channel
decode.
TDS0M: TRANSMIT DS0 MONITOR REGISTER (Address=A9 Hex)
(MSB)
B1
B2
B3
SYMBOL
POSITION
B1
TDS0M.7
B2
B3
B4
B5
B6
B7
B8
TDS0M.6
TDS0M.5
TDS0M.4
TDS0M.3
TDS0M.2
TDS0M.1
TDS0M.0
B4
B5
B6
B7
(LSB)
B8
NAME AND DESCRIPTION
Transmit DS0 Channel Bit 1. MSB of the DS0 channel (first
bit to be transmitted).
Transmit DS0 Channel Bit 2.
Transmit DS0 Channel Bit 3.
Transmit DS0 Channel Bit 4.
Transmit DS0 Channel Bit 5.
Transmit DS0 Channel Bit 6.
Transmit DS0 Channel Bit 7.
Transmit DS0 Channel Bit 8. LSB of the DS0 channel (last
bit to be transmitted).
50 of 110
DS21FT44/DS21FF44
CCR5: COMMON CONTROL REGISTER 5 (Address=AA Hex)
[Repeated here from section 10 for convenience]
(MSB)
–
RESALGN TESALGN
RCM4
SYMBOL
POSITION
–
RESALGN
CCR5.7
CCR5.6
TESALGN
CCR5.5
RCM4
CCR5.4
RCM3
RCM2
RCM1
RCM0
CCR5.3
CCR5.2
CCR5.1
CCR5.0
RCM3
RCM2
RCM1
(LSB)
RCM0
NAME AND DESCRIPTION
Not Assigned. Should be set to zero when written
Receive Elastic Store Align. Setting this bit from a zero to a
one may force the receive elastic store’s write/read pointers to
a minimum separation of half a frame. No action will be taken
if the pointer separation is already greater or equal to half a
frame. If pointer separation is less then half a frame, the
command will be executed and data will be disrupted. Should
be toggled after RSYSCLK has been applied and is stable.
Must be cleared and set again for a subsequent align. See
Section 17 for details.
Transmit Elastic Store Align. Setting this bit from a zero to
a one may force the transmit elastic store’s write/read pointers
to a minimum separation of half a frame. No action will be
taken if the pointer separation is already greater or equal to
half a frame. If pointer separation is less then half a frame, the
command will be executed and data will be disrupted. Should
be toggled after TSYSCLK has been applied and is stable.
Must be cleared and set again for a subsequent align. See
Section 17 for details.
Receive Channel Monitor Bit 4. MSB of a channel decode
that determines which receive channel data will appear in the
RDS0M register. See Section 13 for details.
Receive Channel Monitor Bit 3.
Receive Channel Monitor Bit 2.
Receive Channel Monitor Bit 1.
Receive Channel Monitor Bit 0. LSB of the channel decode.
51 of 110
DS21FT44/DS21FF44
RDS0M: RECEIVE DS0 MONITOR REGISTER (Address = AB Hex)
(MSB)
B1
B2
B3
SYMBOL
POSITION
B1
RDS0M.7
B2
B3
B4
B5
B6
B7
B8
RDS0M.6
RDS0M.5
RDS0M.4
RDS0M.3
RDS0M.2
RDS0M.1
RDS0M.0
14.
B4
B5
B6
B7
(LSB)
B8
NAME AND DESCRIPTION
Receive DS0 Channel Bit 1. MSB of the DS0 channel (first
bit to be received).
Receive DS0 Channel Bit 2.
Receive DS0 Channel Bit 3.
Receive DS0 Channel Bit 4.
Receive DS0 Channel Bit 5.
Receive DS0 Channel Bit 6.
Receive DS0 Channel Bit 7.
Receive DS0 Channel Bit 8. LSB of the DS0 channel (last bit
to be received).
SIGNALING OPERATION
Each framer in the DS21Q44 contains provisions for both processor based (i.e., software based) signaling
bit access and for hardware based access. Both the processor based access and the hardware based access
can be used simultaneously if necessary. The processor based signaling is covered in Section 14.1 and
the hardware based signaling is covered in Section 14.2.
14.1. PROCESSOR BASED SIGNALING
The Channel Associated Signaling (CAS) bits embedded in the E1 stream can be extracted from the
receive stream and inserted into the transmit stream by the framer. Each of the 30 voice channels has
four signaling bits (A/B/C/D) associated with it. The numbers in parenthesis () are the voice channel
associated with a particular signaling bit. The voice channel numbers have been assigned as described in
the ITU documents. Please note that this is different than the channel numbering scheme (1 to 32) that is
used in the rest of the data sheet. For example, voice channel 1 is associated with timeslot 1 (Channel 2)
and voice Channel 30 is associated with timeslot 31 (Channel 32). There is a set of 16 registers for the
receive side (RS1 to RS16) and 16 registers on the transmit side (TS1 to TS16). The signaling registers
are detailed below.
52 of 110
DS21FT44/DS21FF44
RS1 TO RS16: RECEIVE SIGNALING REGISTERS (Address=30 to 3F Hex)
(MSB)
0
A(1)
A(2)
A(3)
A(4)
A(5)
A(6)
A(7)
A(8)
A(9)
A(10)
A(11)
A(12)
A(13)
A(14)
A(15)
0
B(1)
B(2)
B(3)
B(4)
B(5)
B(6)
B(7)
B(8)
B(9)
B(10)
B(11)
B(12)
B(13)
B(14)
B(15)
0
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
B(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
0
D(1)
D(2)
D(3)
D(4)
D(5)
D(6)
B(7)
D(8)
D(9)
D(10)
D(11)
D(12)
D(13)
D(14)
D(15)
SYMBOL
POSITION
X
Y
A(1)
D(30)
RS1.0/1/3
RS1.2
RS2.7
RS16.0
X
A(16)
A(17)
A(18)
A(19)
A(20)
A(21)
B(22)
A(23)
A(24)
A(25)
A(26)
A(27)
A(28)
A(29)
A(30)
Y
B(16)
B(17)
B(18)
B(19)
B(20)
B(21)
B(22)
B(23)
B(24)
B(25)
B(26)
B(27)
B(28)
B(29)
B(30)
X
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
B(22)
C(23)
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
(LSB)
X
D(16)
D(17)
D(18)
D(19)
D(20)
D(21)
B(22)
D(23)
D(24)
D(25)
D(26)
D(27)
D(28)
D(29)
D(30)
RS1 (30)
RS2 (31)
RS3 (32)
RS3 (33)
RS5 (34)
RS6 (35)
RS7 (36)
RS8 (37)
RS9 (38)
RS10 (39)
RS11 (3A)
RS12 (3B)
RS13 (3C)
RS14 (3D)
RS15 (3E)
RS16 (3F)
NAME AND DESCRIPTION
Spare Bits.
Remote Alarm Bit (integrated and reported in SR1.6).
Signaling Bit A for Channel 1
Signaling Bit D for Channel 30.
Each Receive Signaling Register (RS1 to RS16) reports the incoming signaling from two timeslots. The
bits in the Receive Signaling Registers are updated on multiframe boundaries so the user can utilize the
Receive Multiframe Interrupt in the Receive Status Register 2 (SR2.7) to know when to retrieve the
signaling bits. The user has a full 2 ms to retrieve the signaling bits before the data is lost. The RS
registers are updated under all conditions. Their validity should be qualified by checking for
synchronization at the CAS level. In CCS signaling mode, RS1 to RS16 can also be used to extract
signaling information. Via the SR2.7 bit, the user will be informed when the signaling registers have
been loaded with data. The user has 2 ms to retrieve the data before it is lost. The signaling data reported
in RS1 to RS16 is also available at the RSIG and RSER pins.
Three status bits in Status Register 1 (SR1) monitor the contents of registers RS1 through RS16. Status
monitored includes all zeros detection, all ones detection and a change in register contents. The Receive
Signaling All Zeros status bit (SR1.5) is set when over a full multi-frame, RS1 through RS16 contain all
zeros. The Receive Signaling All Ones status bit (SR1.7) is set when over a full multi-frame, RS1
through RS16 contain less than three zeros. A change in the contents of RS1 through RS16 from one
multiframe to the next will cause RSA1 (SR1.7) and RSA0 (SR1.5) status bits to be set at the same time.
The user can enable the INT* pin to toggle low upon detection of a change in signaling by setting either
the IMR1.7 or IMR1.5 bit. Once a signaling change has been detected, the user has at least 1.75 ms to
read the data out of the RS1 to RS16 registers before the data will be lost.
53 of 110
DS21FT44/DS21FF44
TS1 TO TS16: TRANSMIT SIGNALING REGISTERS (Address=40 to 4F Hex)
(MSB)
0
A(1)
A(2)
A(3)
A(4)
A(5)
A(6)
A(7)
A(8)
A(9)
A(10)
A(11)
A(12)
A(13)
A(14)
A(15)
0
B(1)
B(2)
B(3)
B(4)
B(5)
B(6)
B(7)
B(8)
B(9)
B(10)
B(11)
B(12)
B(13)
B(14)
B(15)
0
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
B(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
SYMBOL
POSITION
X
Y
A(1)
D(30)
TS1.0/1/3
TS1.2
TS2.7
TS16.0
0
D(1)
D(2)
D(3)
D(4)
D(5)
D(6)
B(7)
D(8)
D(9)
D(10)
D(11)
D(12)
D(13)
D(14)
D(15)
X
A(16)
A(17)
A(18)
A(19)
A(20)
A(21)
B(22)
A(23)
A(24)
A(25)
A(26)
A(27)
A(28)
A(29)
A(30)
Y
B(16)
B(17)
B(18)
B(19)
B(20)
B(21)
B(22)
B(23)
B(24)
B(25)
B(26)
B(27)
B(28)
B(29)
B(30)
X
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
B(22)
C(23)
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
(LSB)
X
D(16)
D(17)
D(18)
D(19)
D(20)
D(21)
B(22)
D(23)
D(24)
D(25)
D(26)
D(27)
D(28)
D(29)
D(30)
TS1 (40)
TS2 (41)
TS3 (42)
TS4 (43)
TS5 (44)
TS6 (45)
TS7 (46)
TS8 (47)
TS9 (48)
TS10 (49)
TS11 (4A)
TS12 (4B)
TS13 (4C)
TS14 (4D)
TS15 (4E)
TS16 (4F)
NAME AND DESCRIPTION
Spare Bits.
Remote Alarm Bit (integrated and reported in SR1.6).
Signaling Bit A for Channel 1
Signaling Bit D for Channel 30.
Each Transmit Signaling Register (TS1 to TS16) contains the CAS bits for two timeslots that will be
inserted into the outgoing stream if enabled to do so via TCR1.5. On multiframe boundaries, the framer
will load the values present in the Transmit Signaling Register into an outgoing signaling shift register
that is internal to the device. The user can utilize the Transmit Multiframe bit in Status Register 2
(SR2.5) to know when to update the signaling bits. The bit will be set every 2 ms and the user has 2 ms
to update the TSR’s before the old data will be retransmitted. ITU specifications recommend that the
ABCD signaling not be set to all zeros because they will emulate a CAS multiframe alignment word.
The TS1 register is special because it contains the CAS multiframe alignment word in its upper nibble.
The upper nibble must always be set to 0000 or else the terminal at the far end will lose multiframe
synchronization. If the user wishes to transmit a multiframe alarm to the far end, then the TS1.2 bit
should be set to a one. If no alarm is to be transmitted, then the TS1.2 bit should be cleared. The three
remaining bits in TS1 are the spare bits. If they are not used, they should be set to one. In CCS signaling
mode, TS1 to TS16 can also be used to insert signaling information. Via the SR2.5 bit, the user will be
informed when the signaling registers need to be loaded with data. The user has 2 ms to load the data
before the old data will be retransmitted.
Via the CCR3.6 bit, the user has the option to use the Transmit Channel Blocking Registers (TCBRs) to
deter-mine on a channel by channel basis, which signaling bits are to be inserted via the TSRs (the
corresponding bit in the TCBRs=1) and which are to be sourced from the TSER or TSIG pin (the
corresponding bit in the TCBRs=0). See the Transmit Data Flow diagram in Section 22 for more details.
54 of 110
DS21FT44/DS21FF44
14.2. HARDWARE BASED SIGNALING
Receive Side
In the receive side of the hardware based signaling, there are two operating modes for the signaling
buffer; signaling extraction and signaling re–insertion. Signaling extraction involves pulling the signaling
bits from the receive data stream and buffering them over a four multiframe buffer and outputting them in
a serial PCM fashion on a channel–by–channel basis at the RSIG output. This mode is always enabled.
In this mode, the receive elastic store may be enabled or disabled. If the receive elastic store is enabled,
then the backplane clock (RSYSCLK) must be 2.048 MHz. The ABCD signaling bits are output on
RSIG in the lower nibble of each channel. The RSIG data is updated once a multiframe (2 ms) unless a
freeze is in effect. See the timing diagrams in Section 22 for some examples.
The other hardware based signaling operating mode called signaling re–insertion can be invoked by
setting the RSRE control bit high (CCR3.3=1). In this mode, the user will provide a multiframe sync at
the RSYNC pin and the signaling data be re–aligned at the RSER output according to this applied
multiframe boundary in this mode, the elastic store must be enabled the backplane clock must be 2.048
MHz.
The signaling data in the two multiframe buffer will be frozen in a known good state upon either a loss of
synchronization (OOF event), carrier loss, or frame slip. To allow this freeze action to occur, the RFE
control bit (CCR2.0) should be set high. The user can force a freeze by setting the RFF control bit
(CCR2.1) high. Setting the RFF bit high causes the same freezing action as if a loss of synchronization,
carrier loss, or slip has occurred.
The 2 multiframe buffer provides an approximate 1 multiframe delay in the signaling bits provided at the
RSIG pin (and at the RSER pin if RSRE=1 via CCR3.3). When freezing is enabled (RFE=1), the
signaling data will be held in the last known good state until the corrupting error condition subsides.
When the error condition sub-sides, the signaling data will be held in the old state for an additional 3 ms
to 5 ms before being allowed to be updated with new signaling data.
Transmit Side
Via the THSE control bit (CCR3.2), the DS21Q44 can be set up to take the signaling data presented at the
TSIG pin and insert the signaling data into the PCM data stream that is being input at the TSER pin. The
hardware signaling insertion capabilities of each framer are available whether the transmit side elastic
store is enabled or disabled. If the transmit side elastic store is enabled, the backplane clock (TSYSCLK)
must be 2.048 MHz.
When hardware signaling insertion is enabled on a framer (THSE=1), then the user must enable the
Transmit Channel Blocking Register Function Select (TCBFS) control bit (CCR3.6=1). This is needed so
that the CAS multiframe alignment word, multiframe remote alarm, and spare bits can be added to
timeslot 16 in frame 0 of the multiframe. The TS1 register should be programmed with the proper
information. If CCR3.6=1, then a zero in the TCBRs implies that signaling data is to be sourced from
TSER (or TSIG if CCR3.2=1) and a one implies that signaling data for that channel is to be sourced from
the Transmit Signaling (TS) registers. See definition below.
55 of 110
DS21FT44/DS21FF44
TCBR1/TCBR2/TCBR3/TCBR4: DEFINITION WHEN CCR3.6=1
(MSB)
CH20
CH24
CH28
CH32
CH4
CH8
CH12
CH16
CH19
CH23
CH27
CH31
CH3
CH7
CH11
CH15
CH18
CH22
CH26
CH30
CH2
CH6
CH10
CH14
CH17*
CH21
CH25
CH29
(LSB)
CH1*
CH5
CH9
CH13
TCBR1(22)
TCBR2(23)
TCBR3(24)
TCBR4(25)
*=CH1 and CH17 should be set to one to allow the internal TS1 register to create the CAS Multiframe
Alignment Word and Spare/Remote Alarm bits.
The user can also take advantage of this functionality to intermix signaling data from the TSIG pin and
from the internal Transmit Signaling Registers (TS1 to TS16). As an example, assume that the user
wishes to source all the signaling data except for voice channels 5 and 10 from the TSIG pin. In this
application, the following bits and registers would be programmed as follows:
CONTROL BITS
THSE=1 (CCR3.2)
TCBFS=1 (CCR3.6)
T16S=1(TCR1.5)
15.
REGISTER VALUES
TS1=0Bh (MF alignment word, remote alarm etc.)
TCBR1=03h (source timeslot 16, frame 1 data)
TCBR2=01h (source voice Channel 5 signaling data from TS6)
TCBR3=04h (source voice Channel 10 signaling data from TS11)
TCBR4=00h
PER–CHANNEL CODE GENERATION AND LOOPBACK
Each framer in the DS21Q44 can replace data on a channel–by–channel basis in both the transmit and
receive directions. The transmit direction is from the backplane to the E1 line and is covered in Section
15.1. The receive direction is from the E1 line to the backplane and is covered in Section 15.2.
15.1. TRANSMIT SIDE CODE GENERATION
In the transmit direction there are two methods by which channel data from the backplane can be
overwritten with data generated by the framer. The first method which is covered in Section 15.1.1 was a
feature contained in the original DS21Q43 while the second method which is covered in Section 15.1.2 is
a new feature of the DS21Q44.
15.1.1.
Simple Idle Code Insertion and Per–Channel Loopback
The first method involves using the Transmit Idle Registers (TIR1/2/3/4) to determine which of the 32 E1
channels should be overwritten with the code placed in the Transmit Idle Definition Register (TIDR).
This method allows the same 8–bit code to be placed into any of the 32 E1 channels. If this method is
used, then the CCR3.5 control bit must be set to zero.
Each of the bit position in the Transmit Idle Registers (TIR1/TIR2/TIR3/TIR4) represent a DS0 channel
in the outgoing frame. When these bits are set to a one, the corresponding channel will transmit the Idle
Code contained in the Transmit Idle Definition Register (TIDR).
56 of 110
DS21FT44/DS21FF44
The Transmit Idle Registers (TIRs) have an alternate function that allow them to define a Per–Channel
LoopBack (PCLB). If the TIRFS control bit (CCR3.5) is set to one, then the TIRs will determine which
channels (if any) from the backplane should be replaced with the data from the receive side or in other
words, off of the E1 line. If this mode is enabled, then transmit and receive clocks and frame syncs must
be synchronized. One method to accomplish this would be to tie RCLK to TCLK and RFSYNC to
TSYNC. There are no restrictions on which channels can be looped back or on how many channels can
be looped back.
TIR1/TIR2/TIR3: TRANSMIT IDLE REGISTERS (Address=26 to 29 Hex)
[Also used for Per–Channel Loopback]
(MSB)
CH8
CH7
CH6
CH5
CH16
CH15
CH14
CH13
CH24
CH23
CH22
CH21
CH32
CH31
CH30
CH29
CH4
CH12
CH20
CH28
CH3
CH11
CH19
CH27
CH2
CH10
CH18
CH26
(LSB)
CH1
CH9
CH17
CH25
TIR1 (26)
TIR2 (27)
TIR3 (28)
TIR4 (29)
SYMBOLS
POSITIONS
NAME AND DESCRIPTION
CH1 - 32
TIR1.0 - 4.7
Transmit Idle Code Insertion Control Bits.
0 = do not insert the Idle Code in the TIDR into this channel
1 = insert the Idle Code in the TIDR into this channel
NOTE:
If CCR3.5=1, then a zero in the TIRs implies that channel data is to be sourced from TSER and a one
implies that channel data is to be sourced from the output of the receive side framer (i.e., Per–Channel
Loopback; see Figure 6–1).
TIDR: TRANSMIT IDLE DEFINITION REGISTER (Address=2A Hex)
(MSB)
TIDR7
TIDR6
TIDR5
SYMBOL
POSITION
TIDR7
TIDR0
TIDR.7
TIDR.0
15.1.2.
TIDR4
TIDR3
TIDR2
TIDR1
(LSB)
TIDR0
NAME AND DESCRIPTION
MSB of the Idle Code (this bit is transmitted first)
LSB of the Idle Code (this bit is transmitted last)
Per–Channel Code Insertion
The second method involves using the Transmit Channel Control Registers (TCC1/2/3/4) to determine
which of the 32 E1 channels should be overwritten with the code placed in the Transmit Channel
Registers (TC1 to TC32). This method is more flexible than the first in that it allows a different 8–bit
code to be placed into each of the 32 E1 channels.
57 of 110
DS21FT44/DS21FF44
TC1 TO TC32: TRANSMIT CHANNEL REGISTERS (Address=60 to 7F Hex)
(for brevity, only channel one is shown; see Table 8-1 for other register address)
(MSB)
(LSB)
C7
C6
C5
C4
C3
C2
C1
C0
SYMBOL
POSITION
C7
C0
TC1.7
TC1.0
TC1 (60)
NAME AND DESCRIPTION
MSB of the Code (this bit is transmitted first)
LSB of the Code (this bit is transmitted last)
TCC1/TCC2/TCC3/TCC4: TRANSMIT CHANNEL CONTROL REGISTER
(Address=A0 to A3 Hex)
(MSB)
CH8
CH16
CH24
CH32
CH7
CH15
CH23
CH31
CH6
CH14
CH22
CH30
CH5
CH13
CH21
CH29
CH4
CH12
CH20
CH28
CH3
CH11
CH19
CH27
CH2
CH10
CH18
CH26
(LSB)
CH1
CH9
CH17
CH25
TCC1 (A0)
TCC2 (A1)
TCC3 (A2)
TCC4 (A3)
SYMBOL
POSITION
NAME AND DESCRIPTION
CH1 - 32
TCC1.0 - 4.7
Transmit Code Insertion Control Bits
0 = do not insert data from the TC register into the transmit
data stream
1 = insert data from the TC register into the transmit data
stream
15.2. RECEIVE SIDE CODE GENERATION
On the receive side, the Receive Channel Control Registers (RCC1/2/3/4) are used to determine which of
the 32 E1 channels off of the E1 line and going to the backplane should be overwritten with the code
placed in the Receive Channel Registers (RC1 to RC32). This method allows a different 8–bit code to be
placed into each of the 32 E1 channels.
RC1 TO RC32: RECEIVE CHANNEL REGISTERS (Address=80 to 9F Hex)
(for brevity, only channel one is shown; see Table 8-1 for other register address)
(MSB)
(LSB)
C7
C6
C5
C4
C3
C2
C1
C0
SYMBOL
POSITION
C7
C0
RC1.7
RC1.0
RC1 (80)
NAME AND DESCRIPTION
MSB of the Code (this bit is sent first to the backplane)
LSB of the Code (this bit is sent last to the backplane)
58 of 110
DS21FT44/DS21FF44
RCC1/RCC2/RCC3/RCC4: RECEIVE CHANNEL CONTROL REGISTER
(Address = A4 to A7 Hex)
(MSB)
CH8
CH7
CH6
CH16
CH15
CH14
CH24
CH23
CH22
CH32
CH31
CH30
CH5
CH13
CH21
CH29
CH4
CH12
CH20
CH28
CH3
CH11
CH19
CH27
CH2
CH10
CH18
CH26
(LSB)
CH1
CH9
CH17
CH25
RCC1 (A4)
RCC2 (A5)
RCC3 (A6)
RCC4 (A7)
SYMBOL
POSITION
NAME AND DESCRIPTION
CH1 - 32
RCC1.0 - 4.7
Receive Code Insertion Control Bits
0 = do not insert data from the RC register into the receive data
stream
1 = insert data from the RC register into the receive data
stream
16.
CLOCK BLOCKING REGISTERS
The Receive Channel blocking Registers (RCBR1 / RCBR2 / RCBR3 / RCBR4) and the Transmit
Channel Blocking Registers (TCBR1 / TCBR2 / TCBR3 / TCBR4) control RCHBLK and TCHBLK pins
respectively. (The RCHBLK and TCHBLK pins are user programmable outputs that can be forced either
high or low during individual channels). These outputs can be used to block clocks to a USART or
LAPD controller in ISDN–PRI applications. When the appropriate bits are set to a one, the RCHBLK
and TCHBLK pin will be held high during the entire corresponding channel time. See the timing in
Section 22 for an example. The TCBRs have alternate mode of use. Via the CCR3.6 bit, the user has the
option to use the TCBRs to determine on a channel by channel basis, which signaling bits are to be
inserted via the TSRs (the corresponding bit in the TCBRs=1) and which are to be sourced from the
TSER or TSIG pins (the corresponding bit in the TCBR=0). See the timing in Section 22 for an example.
RCBR1/RCBR2/RCBR3/RCBR4: RECEIVE CHANNEL BLOCKING REGISTERS
(Address=2B to 2E Hex)
(MSB)
CH8
CH16
CH24
CH32
CH7
CH15
CH23
CH31
CH6
CH14
CH22
CH30
CH5
CH13
CH21
CH29
SYMBOL
POSITION
CH1 - 32
RCBR1.0 - 4.7
CH4
CH12
CH20
CH28
CH3
CH11
CH19
CH27
CH2
CH10
CH18
CH26
(LSB)
CH1
CH9
CH17
CH25
RCBR1 (2B)
RCBR2 (2C)
RCBR3 (2D)
RCBR4 (2E)
NAME AND DESCRIPTION
Receive Channel Blocking Control Bits.
0 = force the RCHBLK pin to remain low during this channel
time
1 = force the RCHBLK pin high during this channel time
59 of 110
DS21FT44/DS21FF44
TCBR1/TCBR2/TCBR3/TCBR4: TRANSMIT CHANNEL BLOCKING REGISTERS
(Address=22 to 25 Hex)
(MSB)
CH8
CH16
CH24
CH32
CH7
CH15
CH23
CH31
CH6
CH14
CH22
CH30
CH5
CH13
CH21
CH29
SYMBOL
POSITION
CH1 - 32
TCBR1.0 - 4.7
CH4
CH12
CH20
CH28
CH3
CH11
CH19
CH27
CH2
CH10
CH18
CH26
(LSB)
CH1
CH9
CH17
CH25
TCBR1 (22)
TCBR2 (23)
TCBR3 (24)
TCBR4 (25)
NAME AND DESCRIPTION
Transmit Channel Blocking Control Bits.
0 = force the TCHBLK pin to remain low during this channel
time
1 = force the TCHBLK pin high during this channel time
NOTE:
If CCR3.6=1, then a zero in the TCBRs implies that signaling data is to be sourced from TSER (or TSIG
if CCR3.2=1) and a one implies that signaling data for that channel is to be sourced from the Transmit
Signaling (TS) registers. See definition below.
TCBR1/TCBR2/TCBR3/TCBR4: DEFINITION WHEN CCR3.6=1
(MSB)
CH20
CH24
CH28
CH32
CH4
CH8
CH12
CH16
CH19
CH23
CH27
CH31
CH3
CH7
CH11
CH15
CH18
CH22
CH26
CH30
CH2
CH6
CH10
CH14
CH17*
CH21
CH25
CH29
(LSB)
CH1*
CH5
CH9
CH13
TCBR1 (22)
TCBR2 (23)
TCBR3 (24)
TCBR4 (25)
*=CH1 and CH17 should be set to one to allow the internal TS1 register to create the CAS Multiframe
Alignment Word and Spare/Remote Alarm bits.
17.
ELASTIC STORES OPERATION
Each framer in the DS21Q44 contains dual two–frame (512 bits) elastic stores, one for the receive
direction, and one for the transmit direction. These elastic stores have two main purposes. First, they can
be used to rate convert the E1 data stream to 1.544 Mbps (or a multiple of 1.544 Mbps) which is the T1
rate. Secondly, they can be used to absorb the differences in frequency and phase between the E1 data
stream and an asynchronous (i.e., not frequency locked) backplane clock which can be 1.544 MHz or
2.048 MHz. The backplane clock can burst at rates up to 8.192 MHz. Both elastic stores contain full
controlled slip capability which is necessary for this second purpose. Both elastic stores within a framer
are fully independent and no restrictions apply to the sourcing of the various clocks that are applied to
them. The transmit side elastic store can be enabled whether the receive elastic store is enabled or
disabled and vice versa. Also, each elastic store can interface to either a 1.544 MHz or 2.048 MHz
backplane without regard to the backplane rate the other elastic store is interfacing.
Two mechanisms are available to the user for resetting the elastic stores. The Elastic Store Reset
(CCR6.0 & CCR6.1) function forces the elastic stores to a depth of one frame unconditionally. Data is
lost during the reset. The second method, the Elastic Store Align ( CCR5.5 & CCR5.6) forces the elastic
store depth to a minimum depth of half a frame only if the current pointer separation is already less then
half a frame. If a realignment occurs data is lost. In both mechanisms, independent resets are provided
for both the receive and transmit elastic stores.
60 of 110
DS21FT44/DS21FF44
17.1. RECEIVE SIDE
If the receive side elastic store is enabled (RCR2.1=1), then the user must provide either a 1.544 MHz
(RCR2.2 =0) or 2.048 MHz (RCR2.2=1) clock at the RSYSCLK pin. The user has the option of either
providing a frame/multiframe sync at the RSYNC pin (RCR1.5=1) or having the RSYNC pin provide a
pulse on frame/multiframe boundaries (RCR1.5=0). If the user wishes to obtain pulses at the frame
boundary, then RCR1.6 must be set to zero and if the user wishes to have pulses occur at the multiframe
boundary, then RCR1.6 must be set to one. The DS21Q44 will always indicate frame boundaries via the
RFSYNC output whether the elastic store is enabled or not. If the elastic store is enabled, then either
CAS (RCR1.7=0) or CRC4 (RCR1.7=1) multiframe boundaries will be indicated via the RMSYNC
output. If the user selects to apply a 1.544 MHz clock to the RSYSCLK pin, then every fourth channel of
the received E1 data will be deleted and a F–bit position (which will be forced to one) will be inserted.
Hence Channels 1, 5, 9, 13, 17, 21, 25, and 29 (timeslots 0, 4, 8, 12, 16, 20, 24, and 28) will be deleted
from the received E1 data stream. Also, in 1.544 MHz applications, the RCHBLK output will not be
active in Channels 25 through 32 (or in other words, RCBR4 is not active). See Section 22 for timing
details. If the 512-bit elastic buffer either fills or empties, a controlled slip will occur. If the buffer
empties, then a full frame of data (256 bits) will be repeated at RSER and the SR1.4 and RIR.3 bits will
be set to a one. If the buffer fills, then a full frame of data will be deleted and the SR1.4 and RIR.4 bits
will be set to a one.
17.2. TRANSMIT SIDE
The operation of the transmit elastic store is very similar to the receive side. The transmit side elastic
store is enabled via CCR3.7. A 1.544 MHz (CCR3.1=0) or 2.048 MHz (CCR3.1=1) clock can be applied
to the TSYSCLK input. The TSYSCLK can be a bursty clock with rates up to 8.192 MHz. If the user
selects to apply a 1.544 MHz clock to the TSYSCLK pin, then the data sampled at TSER will be ignored
every fourth channel. Hence Channels 1, 5, 9, 13, 17, 21, 25, and 29 (timeslots 0, 4, 8, 12, 16, 20, 24, and
28) will be ignored. The user must supply a 8 KHz frame sync pulse to the TSSYNC input. See Section
22 for timing details. Controlled slips in the transmit elastic store are reported in the SR2.0 bit and the
direction of the slip is reported in the RIR.6 and RIR.7 bits.
18.
ADDITIONAL (Sa) AND INTERNATIONAL (Si) BIT OPERATION
Each framer in the DS21Q44 provides for access to both the Sa and the Si bits via three different
methods. The first is via a hardware scheme using the RLINK/RLCLK and TLINK/ TLCLK pins. The
first method is discussed in Section 18.1. The second involves using the internal RAF/RNAF and
TAF/TNAF registers and is discussed in Section 18.2 The third method which is covered in Section 18.3
involves an expanded version of the second method and is one of the features added to the DS21Q44
from the original DS21Q43 definition.
18.1. HARDWARE SCHEME
On the receive side, all of the received data is reported at the RLINK pin. Via RCR2, the user can control
the RLCLK pin to pulse during any combination of Sa bits. This allows the user to create a clock that can
be used to capture the needed Sa bits. If RSYNC is programmed to output a frame boundary, it will
identify the Si bits. See Section 22 for detailed timing.
On the transmit side, the individual Sa bits can be either sourced from the internal TNAF register (see
Section 18.2 for details) or from the external TLINK pin. Via TCR2, the framer can be programmed to
source any combination of the additional bits from the TLINK pin. If the user wishes to pass the Sa bits
through the framer without them being altered, then the device should be set up to source all five Sa bits
via the TLINK pin and the TLINK pin should be tied to the TSER pin. Si bits can be inserted through the
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DS21FT44/DS21FF44
TSER pin via the clearing of the TCR1.3 bit. Please see the timing diagrams and the transmit data flow
diagram in Section 22 for examples.
18.2. INTERNAL REGISTER SCHEME BASED ON DOUBLE–FRAME
On the receive side, the RAF and RNAF registers will always report the data as it received in the
Additional and International bit locations. The RAF and RNAF registers are updated with the setting of
the Receive Align Frame bit in Status Register 2 (SR2.6). The host can use the SR2.6 bit to know when
to read the RAF and RNAF registers. It has 250 us to retrieve the data before it is lost.
On the transmit side, data is sampled from the TAF and TNAF registers with the setting of the Transmit
Align Frame bit in Status Register 2 (SR2.3). The host can use the SR2.3 bit to know when to update the
TAF and TNAF registers. It has 250 us to update the data or else the old data will be retransmitted. Data
in the Si bit position will be overwritten if the framer is programmed: (1) to source the Si bits from the
TSER pin, (2) in the CRC4 mode, or (3) have automatic E–bit insertion enabled. Data in the Sa bit
position will be overwritten if any of the TCR2.3 to TCR2.7 bits are set to one (please see Section 18.1
for details). Please see the register descriptions for TCR1 and TCR2 and the Transmit Data Flow
diagram in Section 18 for more details.
RAF: RECEIVE ALIGN FRAME REGISTER (Address=2F Hex)
(MSB)
Si
0
0
1
1
0
SYMBOL
POSITION
NAME AND DESCRIPTION
Si
0
0
1
1
0
1
1
RAF.7
RAF.6
RAF.5
RAF.4
RAF.3
RAF.2
RAF.1
RAF.0
International Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit
Frame Alignment Signal Bit.
1
(LSB)
1
RNAF: RECEIVE NON–ALIGN FRAME REGISTER (Address=1F Hex)
(MSB)
Si
1
A
SYMBOL
POSITION
Si
1
A
Sa4
Sa5
Sa6
Sa7
Sa8
RNAF.7
RNAF.6
RNAF.5
RNAF.4
RNAF.3
RNAF.2
RNAF.1
RNAF.0
Sa4
Sa5
Sa6
NAME AND DESCRIPTION
International Bit.
Frame Non–Alignment Signal Bit.
Remote Alarm.
Additional Bit 4.
Additional Bit 5.
Additional Bit 6.
Additional Bit 7.
Additional Bit 8.
62 of 110
Sa7
(LSB)
Sa8
DS21FT44/DS21FF44
TAF: TRANSMIT ALIGN FRAME REGISTER (Address=20 Hex)
(MSB)
(LSB)
Si
0
0
1
1
0
1
1
[Must be programmed with the 7 bit FAS word; the DS21Q44 does not automatically set these bits]
SYMBOL
POSITION
NAME AND DESCRIPTION
Si
0
0
1
1
0
1
1
TAF.7
TAF.6
TAF.5
TAF.4
TAF.3
TAF.2
TAF.1
TAF.0
International Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
Frame Alignment Signal Bit.
TNAF: TRANSMIT NON–ALIGN FRAME REGISTER (Address=21 Hex)
(MSB)
Si
1
A
Sa4
Sa5
Sa6
Sa7
[Bit 2 must be programmed to one; the DS21Q44 does not automatically set this bit]
SYMBOL
POSITION
Si
1
A
Sa4
Sa5
Sa6
Sa7
Sa8
TNAF.7
TNAF.6
TNAF.5
TNAF.4
TNAF.3
TNAF.2
TNAF.1
TNAF.0
(LSB)
Sa8
NAME AND DESCRIPTION
International Bit.
Frame Non–Alignment Signal Bit.
Remote Alarm (used to transmit the alarm).
Additional Bit 4.
Additional Bit 5.
Additional Bit 6.
Additional Bit 7.
Additional Bit 8.
18.3. INTERNAL REGISTER SCHEME BASED ON CRC4 MULTIFRAME
On the receive side, there is a set of eight registers (RSiAF, RSiNAF, RRA, RSa4 to RSa8) that report the
Si and Sa bits as they are received. These registers are updated with the setting of the Receive CRC4
Multiframe bit in Status Register 2 (SR2.1). The host can use the SR2.1 bit to know when to read these
registers. The user has 2 ms to retrieve the data before it is lost. The MSB of each register is the first
received. Please see the register descriptions below and the Transmit Data Flow diagram in Section 22
for more details. On the transmit side, there is also a set of eight registers (TSiAF, TSiNAF, TRA, TSa4
to TSa8) that via the Transmit Sa Bit Control Register (TSaCR), can be programmed to insert both Si and
Sa data. Data is sampled from these registers with the setting of the Transmit Multiframe bit in Status
Register 2 (SR2.5). The host can use the SR2.5 bit to know when to update these registers. It has 2 ms to
update the data or else the old data will be retransmitted. The MSB of each register is the first bit
transmitted. Please see the register descriptions below and the Transmit Data Flow diagram in Section 22
for more details.
63 of 110
DS21FT44/DS21FF44
REGISTER
NAME
RSiAF
RSiNAF
RRA
RSa4
RSa5
RSa6
RSa7
RSa8
TSiAF
TSiNAF
TRA
TSa4
TSa5
TSa6
TSa7
TSa8
ADDRESS (HEX)
FUNCTION
58
59
5A
5B
5C
5D
5E
5F
50
51
52
53
54
55
56
57
The eight Si bits in the align frame.
The eight Si bits in the non–align frame.
The eight reportings of the receive remote alarm (RA).
The eight Sa4 reported in each CRC4 multiframe.
The eight Sa5 reported in each CRC4 multiframe.
The eight Sa6 reported in each CRC4 multiframe.
The eight Sa7 reported in each CRC4 multiframe.
The eight Sa8 reported in each CRC4 multiframe.
The eight Si bits to be inserted into the align frame.
The eight Si bits to be inserted into the non–align frame.
The eight settings of remote alarm (RA).
The eight Sa4 settings in each CRC4 multiframe.
The eight Sa5 settings in each CRC4 multiframe.
The eight Sa6 settings in each CRC4 multiframe.
The eight Sa7 settings in each CRC4 multiframe.
The eight Sa8 settings in each CRC4 multiframe.
TSaCR: TRANSMIT Sa BIT CONTROL REGISTER (Address=1C Hex)
(MSB)
SiAF
SiNAF
RA
SYMBOL
POSITION
SiAF
TSaCR.7
SiNAF
TSaCR.6
RA
TSaCR.5
Sa4
TSaCR.4
Sa5
TSaCR.3
Sa4
Sa5
Sa6
Sa7
(LSB)
Sa8
NAME AND DESCRIPTION
International Bit in Align Frame Insertion Control Bit.
0=do not insert data from the TSiAF register into the transmit
data stream.
1=insert data from the TSiAF register into the transmit data
stream.
International Bit in Non–Align Frame Insertion Control
Bit.
0=do not insert data from the TSiNAF register into the
transmit data stream.
1=insert data from the TSiNAF register into the transmit data
stream.
Remote Alarm Insertion Control Bit.
0=do not insert data from the TRA register into the transmit
data stream.
1=insert data from the TRA register into the transmit data
stream.
Additional Bit 4 Insertion Control Bit.
0=do not insert data from the TSa4 register into the transmit
data stream.
1=insert data from the TSa4 register into the transmit data
stream.
Additional Bit 5 Insertion Control Bit.
0=do not insert data from the TSa5 register into the transmit
data stream.
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DS21FT44/DS21FF44
SYMBOL
19.
POSITION
Sa6
TSaCR.2
Sa7
TSaCR.1
Sa8
TSaCR.0
NAME AND DESCRIPTION
1=insert data from the TSa5 register into the transmit data
stream.
Additional Bit 6 Insertion Control Bit.
0=do not insert data from the TSa6 register into the transmit
data stream.
1=insert data from the TSa6 register into the transmit data
stream.
Additional Bit 7 Insertion Control Bit.
0=do not insert data from the TSa7 register into the transmit
data stream.
1=insert data from the TSa7 register into the transmit data
stream.
Additional Bit 8 Insertion Control Bit.
0=do not insert data from the TSa8 register into the transmit
data stream.
1=insert data from the TSa8 register into the transmit data
stream.
HDLC Controller for the Sa Bits or DS0
Each framer in the DS21Q44 has the ability to extract/insert data from/ into the Sa bit positions (Sa4 to
Sa8) or from/to any multiple of DS0 channels Each framer contains a complete HDLC controller and this
operation is covered in Section 19.1.
19.1. GENERAL OVERVIEW
Each framer contains a complete HDLC controller with 64–byte buffers in both the transmit and receive
directions. The HDLC controller performs all the necessary overhead for generating and receiving a
HDLC formatted message.
The HDLC controller automatically generates and detects flags, generates and checks the CRC check
sum, generates and detects abort sequences, stuffs and destuffs zeros (for transparency), and byte aligns
to the HDLC data stream.
There are eleven registers that the host will use to operate and control the operation of the HDLC
controller. A brief description of the registers is shown in Table 19-1.
HDLC CONTROLLER REGISTER LIST Table 19-1
NAME
FUNCTION
HDLC Control Register (HCR)
general control over the HDLC controller
HDLC Status Register (HSR)
key status information for both transmit and receive
directions
HDLC Interrupt Mask Register (HIMR)
allows/stops status bits to/from causing an interrupt
Receive HDLC Information Register
status information on receive HDLC controller
(RHIR)
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DS21FT44/DS21FF44
NAME
FUNCTION
Receive HDLC FIFO Register (RHFR)
access to 64–byte HDLC FIFO in receive direction
Receive HDLC DS0 Control Register 1
controls the HDLC function when used on DS0 channels
(RDC1)
Receive HDLC DS0 Control Register 2
(RDC2)
Transmit HDLC Information Register
status information on transmit HDLC controller
(THIR)
Transmit HDLC FIFO Register (THFR)
access to 64–byte HDLC FIFO in transmit direction
Transmit HDLC DS0 Control Register 1
controls the HDLC function when used on DS0 channels
(TDC1)
Transmit HDLC DS0 Control Register 2
(TDC2)
19.2. HDLC STATUS REGISTERS
Three of the HDLC controller registers (HSR, RHIR, and THIR) provide status information. When a
particular event has occurred (or is occurring), the appropriate bit in one of these three registers will be
set to a one. Some of the bits in these three status registers are latched and some are real time bits that are
not latched. Section 19.4 contains register descriptions that list which bits are latched and which are not.
With the latched bits, when an event occurs and a bit is set to a one, it will remain set until the user reads
that bit. The bit will be cleared when it is read and it will not be set again until the event has occurred
again. The real time bits report the current instantaneous conditions that are occurring and the history of
these bits is not latched.
Like the other status registers in the framer, the user will always proceed a read of any of the three
registers with a write. The byte written to the register will inform the framer which of the latched bits the
user wishes to read and have cleared (the real time bits are not affected by writing to the status register).
The user will write a byte to one of these registers, with a one in the bit positions he or she wishes to read
and a zero in the bit positions he or she does not wish to obtain the latest information on. When a one is
written to a bit location, the read register will be updated with current value and it will be cleared. When
a zero is written to a bit position, the read register will not be updated and the previous value will be held.
A write to the status and information registers will be immediately followed by a read of the same
register. The read result should be logically AND’ed with the mask byte that was just written and this
value should be written back into the same register to insure that bit does indeed clear. This second write
step is necessary because the alarms and events in the status registers occur asynchronously in respect to
their access via the parallel port. This write–read–write (for polled driven access) or write–read (for
interrupt driven access) scheme allows an external microcontroller or microprocessor to individually poll
certain bits without disturbing the other bits in the register. This operation is key in controlling the
DS21Q44 with higher–order software languages.
66 of 110
DS21FT44/DS21FF44
Like the SR1 and SR2 status registers, the HSR register has the unique ability to initiate a hardware
interrupt via the INT* output pin. Each of the events in the HSR can be either masked or unmasked from
the interrupt pin via the HDLC Interrupt Mask Register (HIMR). Interrupts will force the INT* pin low
when the event occurs. The INT* pin will be allowed to return high (if no other interrupts are present)
when the user reads the event bit that caused the interrupt to occur.
19.3. BASIC OPERATION DETAILS
As a basic guideline for interpreting and sending HDLC messages, the following sequences can be
applied:
Receive a HDLC Message
1.
2.
3.
4.
5.
6.
7.
8.
Enable RPS interrupts.
Wait for interrupt to occur.
Disable RPS interrupt and enable either RPE, RNE, or RHALF interrupt.
Read RHIR to obtain REMPTY status.
A. If REMPTY=0, then record OBYTE, CBYTE, and POK bits and then read the FIFO
A1. If CBYTE=0 then skip to step 5
A2. If CBYTE=1 then skip to step 7
B. If REMPTY=1, then skip to step 6
Repeat step 4.
Wait for interrupt, skip to step 4.
If POK=0, then discard whole packet, if POK=1, accept the packet.
Disable RPE, RNE, or RHALF interrupt, enable RPS interrupt and return to step 1.
Transmit a HDLC Message
1. Make sure HDLC controller is done sending any previous messages and is current sending flags by
checking that the FIFO is empty by reading the TEMPTY status bit in the THIR register.
2. Enable either the THALF or TNF interrupt.
3. Read THIR to obtain TFULL status.
A. If TFULL=0, then write a byte into the FIFO and skip to next step (special case occurs when the
last byte is to be written, in this case set TEOM=1 before writing the byte and then skip to step 6)
B. If TFULL=1, then skip to step 5
4. Repeat step 3.
5. Wait for interrupt, skip to step 3.
6. Disable THALF or TNF interrupt and enable TMEND interrupt.
7. Wait for an interrupt, then read TUDR status bit to make sure packet was transmitted correctly.
67 of 110
DS21FT44/DS21FF44
19.4. HDLC REGISTER DESCRIPTION
HCR: HDLC CONTROL REGISTER (Address=B0 Hex)
(MSB)
–
RHR
TFS
SYMBOL
POSITION
–
RHR
HCR.7
HCR.6
TFS
HCR.5
THR
HCR.4
TABT
HCR.3
TEOM
HCR.2
TZSD
HCR.1
TCRCD
HCR.0
THR
TABT
TEOM
TZSD
(LSB)
TCRCD
NAME AND DESCRIPTION
Not Assigned. Should be set to zero.
Receive HDLC Reset. A 0 to 1 transition will reset the
receive HDLC controller. Must be cleared and set again for a
subsequent reset.
Transmit Flag/Idle Select.
0 = 7Eh.
1 = FFh.
Transmit HDLC Reset. A 0 to 1 transition will reset the
transmit HDLC controller. Must be cleared and set again for a
subsequent reset.
Transmit Abort. A 0 to 1 transition will cause the FIFO
contents to be dumped and one FEh abort to be sent followed
by 7Eh or FFh flags/idle until a new packet is initiated by
writing new data into the FIFO. Must be cleared and set again
for a subsequent abort to be sent.
Transmit End of Message. Should be set to a one just before
the last data byte of a HDLC packet is written into the transmit
FIFO at THFR. The HDLC controller will clear this bit when
the last byte has been transmitted.
Transmit Zero Stuffer Defeat. Overrides internal enable.
0 = enable the zero stuffer (normal operation).
1 = disable the zero stuffer.
Transmit CRC Defeat.
0 = enable CRC generation (normal operation).
1 = disable CRC generation.
HSR: HDLC STATUS REGISTER (Address=B1 Hex)
(MSB)
–
RPE
RPS
SYMBOL
POSITION
–
RPE
HSR.7
HSR.6
RHALF
RNE
THALF
TNF
(LSB)
TMEND
NAME AND DESCRIPTION
Not Assigned. Should be set to zero.
Receive Packet End. Set when the HDLC controller detects
either the finish of a valid message (i.e., CRC check complete)
or when the controller has experienced a message fault such as
a CRC checking error, or an overrun condition, or an abort has
been seen. The setting of this bit prompts the user to read the
RHIR register for details.
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DS21FT44/DS21FF44
SYMBOL
POSITION
RPS
HSR.5
RHALF
HSR.4
RNE
HSR.3
THALF
HSR.2
TNF
HSR.1
TMEND
HSR.0
NAME AND DESCRIPTION
Receive Packet Start. Set when the HDLC controller detects
an opening byte. The setting of this bit prompts the user to
read the RHIR register for details.
Receive FIFO Half Full. Set when the receive 64 byte FIFO
fills beyond the half way point. The setting of this bit prompts
the user to read the RHIR register for details.
Receive FIFO Not Empty. Set when the receive 64 byte
FIFO has at least 1 byte available for a read. The setting of
this bit prompts the user to read the RHIR register for details.
Transmit FIFO Half Empty. Set when the transmit 64 byte
FIFO empties beyond the half way point. The setting of this
bit prompts the user to read the THIR register for details.
Transmit FIFO Not Full. Set when the transmit 64 byte
FIFO has at least 1 byte available. The setting of this bit
prompts the user to read the THIR register for details.
Transmit Message End. Set when the transmit HDLC
controller has finished sending a message. The setting of this
bit prompts the user to read the THIR register for details.
NOTE:
The RPE, RPS, and TMEND bits are latched and will be cleared when read.
HIMR: HDLC INTERRUPT MASK REGISTER (Address=B2 Hex)
(MSB)
–
RPE
RPS
SYMBOL
POSITION
–
RPE
HIMR.7
HIMR.6
RPS
HIMR.5
RHALF
HIMR.4
RNE
HIMR.3
THALF
HIMR.2
RHALF
RNE
THALF
NAME AND DESCRIPTION
Not Assigned. Should be set to zero.
Receive Packet End.
0 = interrupt masked.
1 = interrupt enabled.
Receive Packet Start.
0 = interrupt masked.
1 = interrupt enabled.
Receive FIFO Half Full.
0 = interrupt masked.
1 = interrupt enabled.
Receive FIFO Not Empty.
0 = interrupt masked.
1 = interrupt enabled.
Transmit FIFO Half Empty.
0 = interrupt masked.
1 = interrupt enabled.
69 of 110
TNF
(LSB)
TMEND
DS21FT44/DS21FF44
TNF
HIMR.1
TMEND
HIMR.0
Transmit FIFO Not Full.
0 = interrupt masked.
1 = interrupt enabled.
Transmit Message End.
0 = interrupt masked.
1 = interrupt enabled.
RHIR: RECEIVE HDLC INFORMATION REGISTER (Address=B3 Hex)
(MSB)
RABT
RCRCE
ROVR
SYMBOL
POSITION
RABT
RHIR.7
RCRCE
ROVR
RHIR.6
RHIR.5
RVM
RHIR.4
REMPTY
RHIR.3
POK
RHIR.2
CBYTE
RHIR.1
OBYTE
RHIR.0
RVM
REMPTY
POK
CBYTE
(LSB)
OBYTE
NAME AND DESCRIPTION
Abort Sequence Detected. Set whenever the HDLC
controller sees 7 or more ones in a row.
CRC Error. Set when the CRC checksum is in error.
Overrun. Set when the HDLC controller has attempted to
write a byte into an already full receive FIFO.
Valid Message. Set when the HDLC controller has detected
and checked a complete HDLC packet.
Empty. A real–time bit that is set high when the receive FIFO
is empty.
Packet OK. Set when the byte available for reading in the
receive FIFO at RHFR is the last byte of a valid message (and
hence no abort was seen, no overrun occurred, and the CRC
was correct).
Closing Byte. Set when the byte available for reading in the
receive FIFO at RFDL is the last byte of a message (whether
the message was valid or not).
Opening Byte. Set when the byte available for reading in the
receive FIFO at RHFR is the first byte of a message.
NOTE:
The RABT, RCRCE, ROVR, and RVM bits are latched and will be cleared when read.
RHFR: RECEIVE HDLC FIFO REGISTER (Address=B4 Hex)
(MSB)
HDLC7
HDLC6
HDLC5
SYMBOL
POSITION
HDLC7
HDLC6
HDLC5
HDLC4
HDLC3
HDLC2
HDLC1
HDLC0
RHFR.7
RHFR.6
RHFR.5
RHFR.4
RHFR.3
RHFR.2
RHFR.1
RHFR.0
HDLC4
HDLC3
HDLC2
HDLC1
(LSB)
HDLC0
NAME AND DESCRIPTION
HDLC Data Bit 7. MSB of a HDLC packet data byte.
HDLC Data Bit 6.
HDLC Data Bit 5.
HDLC Data Bit 4.
HDLC Data Bit 3.
HDLC Data Bit 2.
HDLC Data Bit 1.
HDLC Data Bit 0. LSB of a HDLC packet data byte.
70 of 110
DS21FT44/DS21FF44
THIR: TRANSMIT HDLC INFORMATION REGISTER (Address=B6 Hex)
(MSB)
–
–
–
SYMBOL
POSITION
–
–
–
–
–
TEMPTY
THIR.7
THIR.6
THIR.5
THIR.4
THIR.3
THIR.2
TFULL
THIR.1
TUDR
THIR.0
–
–
EMPTY
TFULL
(LSB)
TUDR
NAME AND DESCRIPTION
Not Assigned. Could be any value when read.
Not Assigned. Could be any value when read.
Not Assigned. Could be any value when read.
Not Assigned. Could be any value when read.
Not Assigned. Could be any value when read.
Transmit FIFO Empty. A real–time bit that is set high when
the FIFO is empty.
Transmit FIFO Full. A real–time bit that is set high when the
FIFO is full.
Transmit FIFO Underrun. Set when the transmit FIFO
unwantedly empties out and an abort is automatically sent.
NOTE:
The TUDR bit is latched and will be cleared when read.
THFR: TRANSMIT HDLC FIFO REGISTER (Address=B7 Hex)
(MSB)
HDLC7
HDLC6
HDLC5
SYMBOL
POSITION
HDLC7
HDLC6
HDLC5
HDLC4
HDLC3
HDLC2
HDLC1
HDLC0
THFR.7
THFR.6
THFR.5
THFR.4
THFR.3
THFR.2
THFR.1
THFR.0
HDLC4
HDLC3
HDLC2
HDLC1
(LSB)
HDLC0
NAME AND DESCRIPTION
HDLC Data Bit 7. MSB of a HDLC packet data byte.
HDLC Data Bit 6.
HDLC Data Bit 5.
HDLC Data Bit 4.
HDLC Data Bit 3.
HDLC Data Bit 2.
HDLC Data Bit 1.
HDLC Data Bit 0. LSB of a HDLC packet data byte.
RDC1: RECEIVE HDLC DS0 CONTROL REGISTER 1 (Address=B8 Hex)
(MSB)
RHS
RSaDS
RDS0M
SYMBOL
POSITION
RHS
RDC1.7
RD4
RD3
RD2
RD1
(LSB)
RD0
NAME AND DESCRIPTION
Receive HDLC source
0 = Sa bits defined by RCR2.3 to RCR2.7.
1 = Sa bits or DS0 channels defined by RDC1 (see bits defined
below).
71 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
RSaDS
RDC1.6
RDS0M
RDC1.5
RD4
RD3
RD2
RD1
RD0
RDC1.4
RDC1.3
RDC1.2
RDC1.1
RDC1.0
NAME AND DESCRIPTION
Receive Sa Bit / DS0 Select.
0 = route Sa bits to the HDLC controller. RD0 to RD4 defines
which Sa bits are to be routed. RD4 corresponds to Sa4, RD3
to Sa5, RD2 to Sa6, RD1 to Sa7 and RD0 to Sa8.
1 = route DS0 channels into the HDLC controller. RDC1.5 is
used to determine how the DS0 channels are selected.
DS0 Selection Mode.
0 = utilize the RD0 to RD4 bits to select which single DS0
channel to use.
1 = utilize the RCHBLK control registers to select which DS0
channels to use.
DS0 Channel Select Bit 4. MSB of the DS0 channel select.
DS0 Channel Select Bit 3.
DS0 Channel Select Bit 2.
DS0 Channel Select Bit 1.
DS0 Channel Select Bit 0. LSB of the DS0 channel select.
RDC2: RECEIVE HDLC DS0 CONTROL REGISTER 2 (Address=B9 Hex)
(MSB)
RDB8
RDB7
RDB6
SYMBOL
POSITION
RDB8
RDC2.7
RDB7
RDC2.6
RDB6
RDC2.5
RDB5
RDC2.4
RDB4
RDC2.3
RDB3
RDC2.2
RDB2
RDC2.1
RDB1
RDC2.0
RDB5
RDB4
RDB3
RDB2
(LSB)
RDB1
NAME AND DESCRIPTION
DS0 Bit 8 Suppress Enable. MSB of the DS0. Set to one to
stop this bit from being used.
DS0 Bit 7 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 6 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 5 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 4 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 3 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 2 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 1 Suppress Enable. LSB of the DS0. Set to one to
stop this bit from being used.
72 of 110
DS21FT44/DS21FF44
TDC1: TRANSMIT HDLC DS0 CONTROL REGISTER 1 (Address = BA Hex)
(MSB)
THE
TSaDS
TDS0M
SYMBOL
POSITION
THE
TDC1.7
TSaDS
TDC1.6
TDS0M
TDC1.5
TD4
TD3
TD2
TD1
TD0
TDC1.4
TDC1.3
TDC1.2
TDC1.1
TDC1.0
TD4
TD3
TD2
TD1
(LSB)
TD0
NAME AND DESCRIPTION
Transmit HDLC Enable.
0 = disable HDLC controller (no data inserted by HDLC
controller into the transmit data stream)
1 = enable HDLC controller to allow insertion of HDLC data
into either the Sa position or multiple DS0 channels as defined
by TDC1 (see bit definitions below).
Transmit Sa Bit / DS0 Select. This bit is ignored if TDC1.7
is set to zero.
0 = route Sa bits from the HDLC controller. TD0 to TD4
defines which Sa bits are to be routed. TD4 corresponds to
Sa4, TD3 to Sa5, TD2 to Sa6, TD1 to Sa7 and TD0 to Sa8.
1 = route DS0 channels from the HDLC controller. TDC1.5 is
used to determine how the DS0 channels are selected.
DS0 Selection Mode.
0 = utilize the TD0 to TD4 bits to select which single DS0
channel to use.
1 = utilize the TCHBLK control registers to select which DS0
channels to use.
DS0 Channel Select Bit 4. MSB of the DS0 channel select.
DS0 Channel Select Bit 3.
DS0 Channel Select Bit 2.
DS0 Channel Select Bit 1.
DS0 Channel Select Bit 0. LSB of the DS0 channel select.
TDC2: TRANSMIT HDLC DS0 CONTROL REGISTER 2 (Address = BB Hex)
(MSB)
TDB8
TDB7
TDB6
SYMBOL
POSITION
TDB8
TDC2.7
TDB7
TDC2.6
TDB6
TDC2.5
TDB5
TDC2.4
TDB4
TDC2.3
TDB5
TDB4
TDB3
TDB2
(LSB)
TDB1
NAME AND DESCRIPTION
DS0 Bit 8 Suppress Enable. MSB of the DS0. Set to one to
stop this bit from being used.
DS0 Bit 7 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 6 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 5 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 4 Suppress Enable. Set to one to stop this bit from
being used.
73 of 110
DS21FT44/DS21FF44
SYMBOL
POSITION
TDB3
TDC2.2
TDB2
TDC2.1
TDB1
TDC2.0
20.
NAME AND DESCRIPTION
DS0 Bit 3 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 2 Suppress Enable. Set to one to stop this bit from
being used.
DS0 Bit 1 Suppress Enable. LSB of the DS0. Set to one to
stop this bit from being used.
INTERLEAVED PCM BUS OPERATION
In many architectures, the outputs of individual framers are combined into higher speed serial buses to
simplify transport across the system. The DS21Q44 can be configured to allow each framer’s data and
signaling busses to be multiplexed into higher speed data and signaling busses eliminating external
hardware saving board space and cost.
The interleaved PCM bus option supports two bus speeds and interleave modes. The 4.096 MHz bus
speed allows two framers to share a common bus. The 8.192 MHz bus speed allows all four of the
DS21Q44’s framers to share a common bus. Framers can interleave their data either on byte or frame
boundaries. Framers that share a common bus must be configured through software and require several
device pins to be connected together externally (see figures 20-1 & 20-2). Each framer’s elastic stores
must be enabled and configured for 2.048 MHz operation. The signal RSYNC must be configured as an
input on each framer.
For all bus configurations, one framer will be configured as the master device and the remaining framers
on the shared bus will be configured as slave devices. Refer to the IBO register description below for
more detail. In the 4.096 MHz bus configuration there is one master and one slave per bus. Figure 20-1
shows the DS21Q44 configured to support two 4.096 MHz buses. Bus 1 consists of framers 0 and 1. Bus
2 consists of framers 2 and 3. Framers 0 and 2 are programmed as master devices. Framers 1 and 3 are
programmed as slave devices. In the 8.192 MHz bus configuration there is one master and three slaves.
Figure 20-2 shows the DS21Q44 configured to support a 8.192 MHz bus. Framer 0 is programmed as the
master device. Framers 1, 2 and 3 are programmed as slave devices. Consult timing diagrams in section
22 for additional information.
When using the frame interleave mode, all framers that share an interleaved bus must have receive signals
(RPOS & RNEG) that are synchronous with each other. The received signals must originate from the
same clock reference. This restriction does not apply in the byte interleave mode.
IBO: INTERLEAVE BUS OPERATION REGISTER (Address = B5 Hex)
(MSB)
–
–
–
SYMBOL
POSITION
–
–
–
–
IBO.7
IBO.6
IBO.5
IBO.4
–
IBOEN
INTSEL
NAME AND DESCRIPTION
Not Assigned.
Not Assigned.
Not Assigned.
Not Assigned.
Should be set to 0.
Should be set to 0.
Should be set to 0.
Should be set to 0.
74 of 110
MSEL0
(LSB)
MSEL1
DS21FT44/DS21FF44
SYMBOL
POSITION
IBOEN
IBO.3
INTSEL
IBO.2
MSEL0
MSEL1
IBO.1
IBO.0
NAME AND DESCRIPTION
Interleave Bus Operation Enable
0 = Interleave Bus Operation disabled.
1 = Interleave Bus Operation enabled.
Interleave Type Select
0 = Byte interleave.
1 = Frame interleave.
Master Device Bus Select Bit 0 See table 20-1.
Master Device Bus Select Bit 1 See table 20-1.
Master Device Bus Select Table 20-1
MSEL1
0
0
1
1
MSEL0
0
1
0
1
Function
Slave device.
Master device with 1 slave device (4.096 MHz bus rate)
Master device with 3 slave devices (8.192 MHz bus rate)
Reserved
75 of 110
DS21FT44/DS21FF44
4.096 MHz Interleaved Bus External Pin Connection Example Figure 20-1
FRAMER 0
FRAMER 1
FRAMER 2
FRAMER 3
RSYSCLK0
RSYSCLK1
RSYSCLK2
RSYSCLK3
TSYSCLK0
TSYSCLK1
TSYSCLK2
TSYSCLK3
RSYNC0
RSYNC1
RSYNC2
RSYNC3
TSSYNC0
TSSYNC1
TSSYNC2
TSSYNC3
RSER0
RSER1
RSER2
RSER3
TSER0
TSER1
TSER2
TSER3
RSIG0
RSIG1
RSIG2
RSIG3
TSIG0
TSIG1
TSIG2
TSIG3
SYSCLK
SYNC INPUT
RSER
TSER
RSIG
TSIG
SYSCLK
SYNC INPUT
RSER
TSER
RSIG
TSIG
Bus 2
Bus 1
8.192 MHz Interleaved Bus External Pin Connection Example Figure 20-2
FRAMER 0
FRAMER 1
FRAMER 2
FRAMER 3
RSYSCLK0
RSYSCLK1
RSYSCLK2
RSYSCLK3
TSYSCLK0
TSYSCLK1
TSYSCLK2
TSYSCLK3
RSYNC0
RSYNC1
RSYNC2
RSYNC3
TSSYNC0
TSSYNC1
TSSYNC2
TSSYNC3
RSER0
RSER1
RSER2
RSER3
TSER0
TSER1
TSER2
TSER3
RSIG0
RSIG1
RSIG2
RSIG3
TSIG0
TSIG1
TSIG2
TSIG3
SYSCLK
SYNC INPUT
RSER
TSER
RSIG
TSIG
76 of 110
DS21FT44/DS21FF44
21.
JTAG-BOUNDARY SCAN ARCHITECTURE AND TEST ACCESS PORT
21.1. DESCRIPTION
The DS21Q44 IEEE 1149.1 design supports the standard instruction codes SAMPLE/PRELOAD,
BYPASS, and EXTEST. Optional public instructions included with this design are HIGHZ, CLAMP,
and IDCODE. See Figure 21-1 for a block diagram. The DS21Q44 contains the following items which
meet the requirements set by the IEEE 1149.1 Standard Test Access Port and Boundary Scan
Architecture. The DS21FT42 should be considered as 3 individual DS21Q42 devices. The DS21FF44
should be considered as 4 individual DS21Q44 devices.
Test Access Port (TAP)
TAP Controller
Instruction Register
Bypass Register
Boundary Scan Register
Device Identification Register
The JTAG feature is only available when the DS21Q44 feature set is selected (FMS = 0). The JTAG
feature is disabled when the DS21Q44 is configured for emulation of the DS21Q43 (FMS = 1). FMS is
tied to ground for the DS21FF44/DS21FT44.
Details on Boundary Scan Architecture and the Test Access Port can be found in IEEE 1149.1-1990,
IEEE 1149.1a-1993, and IEEE 1149.1b-1994.
The Test Access Port has the necessary interface pins; JTRST*, JTCLK, JTMS, JTDI, and JTDO. See
the pin descriptions for details.
Boundary Scan Architecture Figure 21-1
Boundary Scan
Register
Identification
Register
Bypass
Register
MUX
Instruction
Register
Select
Test Access Port
Controller
+V
10K
+V
10K
JTDI
Output Enable
+V
10K
JTMS
JTCLK
JTRST
77 of 110
JTDO
DS21FT44/DS21FF44
21.2. TAP CONTROLLER STATE MACHINE
This section covers the details on the operation of the Test Access Port (TAP) Controller State Machine.
Please see Figure 21.2 for details on each of the states described below.
TAP Controller
The TAP controller is a finite state machine that responds to the logic level at JTMS on the rising edge of
JTCLK.
Test-Logic-Reset
Upon power up of the DS21Q44, the TAP Controller will be in the Test-Logic-Reset state. The
Instruction register will contain the IDCODE instruction. All system logic of the DS21Q44 will operate
normally.
Run-Test-Idle
The Run-Test-Idle is used between scan operations or during specific tests. The Instruction register and
Test registers will remain idle.
Select-DR-Scan
All test registers retain their previous state. With JTMS low, a rising edge of JTCLK moves the
controller into the Capture-DR state and will initiate a scan sequence. JTMS HIGH during a rising edge
on JTCLK moves the controller to the Select-IR
Capture-DR
Data may be parallel-loaded into the Test Data registers selected by the current instruction. If the
instruction does not call for a parallel load or the selected register does not allow parallel loads, the Test
register will remain at its current value. On the rising edge of JTCLK, the controller will go to the ShiftDR state if JTMS is low or it will go to the Exit1-DR state if JTMS is high.
Shift-DR
The Test Data register selected by the current instruction will be connected between JTDI and JTDO and
will shift data one stage towards its serial output on each rising edge of JTCLK. If a Test Register
selected by the current instruction is not placed in the serial path, it will maintain its previous state.
Exit1-DR
While in this state, a rising edge on JTCLK with JTMS high will put the controller in the Update-DR
state, and terminate the scanning process. A rising edge on JTCLK with JTMS low will put the controller
in the Pause-DR state.
Pause-DR
Shifting of the test registers is halted while in this state. All Test registers selected by the current
instruction will retain their previous state. The controller will remain in this state while JTMS is low. A
rising edge on JTCLK with JTMS high will put the controller in the Exit2-DR state.
Exit2-DR
While in this state, a rising edge on JTCLK with JTMS high will put the controller in the Update-DR
state and terminate the scanning process. A rising edge on JTCLK with JTMS low will enter the ShiftDR state.
78 of 110
DS21FT44/DS21FF44
Update-DR
A falling edge on JTCLK while in the Update-DR state will latch the data from the shift register path of
the Test registers into the data output latches. This prevents changes at the parallel output due to changes
in the shift register. A rising edge on JTCLK with JTMS low, will put the controller in the Run-Test-Idle
state. With JTMS high, the controller will enter the Select-DR-Scan state.
Select-IR-Scan
All test registers retain their previous state. The instruction register will remain unchanged during this
state. With JTMS low, a rising edge of JTCLK moves the controller into the Capture-IR state and will
initiate a scan sequence for the Instruction register. JTMS high during a rising edge on JTCLK puts the
controller back into the Test-Logic-Reset state.
Capture-IR
The Capture-IR state is used to load the shift register in the instruction register with a fixed value. This
value is loaded on the rising edge of JTCLK. If JTMS is high on the rising edge of JTCLK, the controller
will enter the Exit1-IR state. If JTMS is low on the rising edge of JTCLK, the controller will enter the
Shift-IR state.
Shift-IR
In this state, the shift register in the instruction register is connected between JTDI and JTDO and shifts
data one stage for every rising edge of JTCLK towards the serial output. The parallel registers, as well as
all Test registers remain at their previous states. A rising edge on JTCLK with JTMS high will move the
controller to the Exit1-IR state. A rising edge on JTCLK with JTMS low will keep the controller in the
Shift-IR state while moving data one stage thorough the instruction shift register.
Exit1-IR
A rising edge on JTCLK with JTMS low will put the controller in the Pause-IR state. If JTMS is high on
the rising edge of JTCLK, the controller will enter the Update-IR state and terminate the scanning
process.
Pause-IR
Shifting of the instruction shift register is halted temporarily. With JTMS high, a rising edge on JTCLK
will put the controller in the Exit2-IR state. The controller will remain in the Pause-IR state if JTMS is
low during a rising edge on JTCLK.
Exit2-IR
A rising edge on JTCLK with JTMS low will put the controller in the Update-IR state. The controller
will loop back to Shift-IR if JTMS is high during a rising edge of JTCLK in this state.
Update-IR
The instruction code shifted into the instruction shift register is latched into the parallel output on the
falling edge of JTCLK as the controller enters this state. Once latched, this instruction becomes the
current instruction. A rising edge on JTCLK with JTMS low, will put the controller in the Run-Test-Idle
state. With JTMS high, the controller will enter the Select-DR-Scan state.
79 of 110
DS21FT44/DS21FF44
TAP Controller State Machine Figure 21-2
1
0
Test Logic
Reset
0
Run Test/
Idle
1
Select
DR-Scan
1
Select
IR-Scan
0
1
0
1
Capture DR
Capture IR
0
Shift DR
0
Shift IR
0
1
Exit DR
1
Exit IR
Pause IR
0
0
1
0
Exit2 DR
Exit2 IR
1
1
Update DR
1
1
0
1
0
0
1
0
Pause DR
1
Update IR
0
1
0
21.3. INSTRUCTION REGISTER AND INSTRUCTIONS
The instruction register contains a shift register as well as a latched parallel output and is 3 bits in length.
When the TAP controller enters the Shift-IR state, the instruction shift register will be connected between
JTDI and JTDO. While in the Shift-IR state, a rising edge on JTCLK with JTMS low will shift the data
one stage towards the serial output at JTDO. A rising edge on JTCLK in the Exit1-IR state or the Exit2IR state with JTMS high will move the controller to the Update-IR state The falling edge of that same
JTCLK will latch the data in the instruction shift register to the instruction parallel output. Instructions
supported by the DS21Q44 with their respective operational binary codes are shown in Table 21-1.
Instruction Codes For The DS21Q44 IEEE 1149.1 Architecture Table 21-1
Instruction
Selected Register
SAMPLE/PRELOAD
BYPASS
EXTEST
CLAMP
HIGHZ
IDCODE
Boundary Scan
Bypass
Boundary Scan
Boundary Scan
Boundary Scan
Device Identification
80 of 110
Instruction Code
010
111
000
011
100
001
DS21FT44/DS21FF44
SAMPLE/PRELOAD
A mandatory instruction for the IEEE 1149.1 specification. This instruction supports two functions. The
digital I/Os of the DS21Q44 can be sampled at the boundary scan register without interfering with the
normal operation of the device by using the Capture-DR state. SAMPLE/PRELOAD also allows the
DS21Q44 to shift data into the boundary scan register via JTDI using the Shift-DR state.
EXTEST
EXTEST allows testing of all interconnections to the DS21Q44. When the EXTEST instruction is
latched in the instruction register, the following actions occur. Once enabled via the Update-IR state, the
parallel outputs of all digital output pins will be driven. The boundary scan register will be connected
between JTDI and JTDO. The Capture-DR will sample all digital inputs into the boundary scan register.
BYPASS
When the BYPASS instruction is latched into the parallel instruction register, JTDI connects to JTDO
through the 1 bit bypass test register. This allows data to pass from JTDI to JTDO not affecting the
device’s normal operation.
IDCODE
When the IDCODE instruction is latched into the parallel instruction register, the Identification Test
register is selected. The device identification code will be loaded into the Identification register on the
rising edge of JTCLK following entry into the Capture-DR state. Shift-DR can be used to shift the
identification code out serially via JTDO. During Test-Logic-Reset, the identification code is forced into
the instruction register’s parallel output. The ID code will always have a ‘1’ in the LSB position. The
next 11 bits identify the manufacturer’s JEDEC number and number of continuation bytes followed by 16
bits for the device and 4 bits for the version. See Table 21-2. Table 21-3 lists the device ID codes for the
DS21Q42 and DS21Q44 devices.
ID Code Structure Table 21-2
MSB
LSB
Contents
Version
(Contact Factory)
Device ID
(See Table 21-3)
JEDEC
“00010100001”
“1”
Length
4 bits
16 bits
11 bits
1 bit
Device ID Codes Table 21-3
DEVICE
DS21Q42
DS21Q44
16-BIT NUMBER
0000h
0001h
HIGHZ
All digital outputs of the DS21Q44 will be placed in a high impedance state. The BYPASS register will
be connected between JTDI and JTDO.
CLAMP
All digital outputs of the DS21Q44 will output data from the boundary scan parallel output while
connecting the bypass register between JTDI and JTDO. The outputs will not change during the CLAMP
instruction.
81 of 110
DS21FT44/DS21FF44
21.4. TEST REGISTERS
IEEE 1149.1 requires a minimum of two test registers; the bypass register and the boundary scan register.
An optional test register has been included with the DS21Q44 design. This test register is the
identification register and is used in conjunction with the IDCODE instruction and the Test-Logic-Reset
state of the TAP controller.
Boundary Scan Register
This register contains both a shift register path and a latched parallel output for all control cells and
digital I/O cells and is 126 bits in length. Table 21-3 shows all of the cell bit locations and definitions.
Bypass Register
This is a single 1 bit shift register used in conjunction with the BYPASS, CLAMP, and HIGHZ
instructions, which provides a short path between JTDI and JTDO.
Identification Register
The identification register contains a 32-bit shift register and a 32 bit latched parallel output. This
register is selected during the IDCODE instruction and when the TAP controller is in the Test-LogicReset state.
Boundary Scan Register Description Table 21-4
MCM
LEAD
(DIE1)
B7
G20
H20
G19
H19
G18
H18
G17
H17
W15
-
B6
T8
L20
M20
L19
M19
L18
M18
L17
MCM
LEAD
(DIE2)
MCM
LEAD
(DIE3)
MCM
LEAD
(DIE4)
G20
H20
G19
H19
G18
H18
G17
H17
W15
G20
H20
G19
H19
G18
H18
G17
H17
W15
G20
H20
G19
H19
G18
H18
G17
H17
W15
Y4
L20
M20
L19
M19
L18
M18
L17
Y15
L20
M20
L19
M19
L18
M18
L17
E19
L20
M20
L19
M19
L18
M18
L17
SCAN
REGIST
ER BIT
102
60
59
58
57
56
55
54
37
22
94
DS21Q42
DIE
SYMBOL
8MCLK
A0
A1
A2
A3
A4
A5
A6/ALE (AS)
A7
BTS
BUS.cntl
100
23
93
92
91
90
89
88
87
CLKSI
CS*
D0 or AD0
D1 or AD1
D2 or AD2
D3 or AD3
D4 or AD4
D5 or AD5
D6 or AD6
82 of 110
CONTROL
BIT
DESCRIPTION
TYPE
O
I
I
I
I
I
I
I
I
I
0 = D0-D7 or
AD0-AD7 are
inputs
1 = D0-D7 or
AD0-AD7 are
outputs
I
I
I/O
I/O
I/O
I/O
I/O
I/O
I/O
DS21FT44/DS21FF44
MCM
LEAD
(DIE1)
M17
Y14
W14
G16
V14
E10
MCM
LEAD
(DIE2)
M17
Y14
W14
G16
V14
E10
MCM
LEAD
(DIE3)
M17
Y14
W14
G16
V14
E10
MCM
LEAD
(DIE4)
M17
Y14
W14
G16
V14
E10
A19
SCAN
REGIST
ER BIT
86
25
24
53
-
T17
H16
K17
P17
Y8
W12
V17
U17
T9
W10
Y18
N17
E18
U9
W11
W17
T20
T10
V11
Y19
R19
U11
Y12
V16
T16
U10
Y11
W19
U20
T11
H16
K17
P17
D16
K20
B18
B16
D14
P20
C18
C12
E18
E14
N20
C20
B13
D15
J18
A20
A14
E16
F20
C16
A12
E15
K19
C17
A15
J17
19
72
39
5
107
76
43
9
111
21
75
42
8
110
74
41
7
109
68
33
1
103
73
40
6
108
69
70
DS21Q42
DIE
SYMBOL
D7 or AD7
FS0
FS1
INT*
JTCLK
JTDI
JTDOF
JTDOT
JTMS
JTRST*
MUX
RCHBLK0
RCHBLK1
RCHBLK2
RCHBLK3
RCLK0
RCLK1
RCLK2
RCLK3
RD*/(DS*)
RNEG0
RNEG1
RNEG2
RNEG3
RPOS0
RPOS1
RPOS2
RPOS3
RSER0
RSER1
RSER2
RSER3
RSIG0
RSIG1
RSIG2
RSIG3
RSYNC0
RSYNC0.cntl
H16
K17
P17
C2
G3
E6
A8
A2
K1
D10
B9
E18
B2
H2
D9
A9
A1
H1
H4
C9
C1
H3
C6
C8
D3
G2
D4
D8
B1
-
H16
K17
P17
N1
Y1
U6
N5
M3
V1
W6
J3
E18
M2
V3
V7
P3
M1
W2
V5
P4
P1
W4
T7
N4
N2
V4
V6
K5
N3
G1
Y2
V13
J19
34
RSYNC1
83 of 110
CONTROL
BIT
DESCRIPTION
TYPE
I/O
I
I
O
I
I
O
O
I
I
I
O
O
O
O
I
I
I
I
I
I
I
I
I
I
I
I
I
O
O
O
O
O
O
O
O
I/O
0 = RSYNC0 an
input
1 = RSYNC0 an
output
I/O
DS21FT44/DS21FF44
MCM
LEAD
(DIE1)
-
MCM
LEAD
(DIE2)
MCM
LEAD
(DIE3)
MCM
LEAD
(DIE4)
SCAN
REGIST
ER BIT
35
DS21Q42
DIE
SYMBOL
RSYNC1.cntl
D6
-
U5
V15
B17
2
3
RSYNC2
RSYNC2.cntl
A7
-
J4
P18
B12
104
105
RSYNC3
RSYNC3.cntl
B5
E2
E5
B8
D1
H5
C5
A5
A13
C3
J1
F5
A10
B3
J2
J5
B10
B4
E1
F3
D7
C4
F1
G4
C10
A3
F2
G5
E8
E3
M4
T2
Y5
W3
R1
Y3
T6
K2
A13
L1
V2
V8
P5
L2
W1
W7
R3
L5
T1
Y6
T3
L3
U2
V9
R5
L4
U1
Y7
R4
R2
T4
Y9
U12
R17
U13
Y13
T18
P16
A13
U14
V12
W18
T19
T14
Y10
V18
V20
M16
W9
W16
W20
U15
V10
U18
R18
T15
W8
Y17
U19
T13
E13
N18
E20
C14
K16
F19
E17
C11
A13
D11
K18
C19
B15
E12
N19
B19
B14
D13
F17
D18
A18
E11
P19
B20
A16
C13
R20
D20
A17
J16
71
38
4
106
65
31
125
99
26
79
46
12
114
80
47
13
115
84
51
17
119
82
49
15
117
83
50
16
118
62
*RSYSCLK0
*RSYSCLK1
*RSYSCLK2
*RSYSCLK3
TCLK0
TCLK1
TCLK2
TCLK3
TEST
TNEG0
TNEG1
TNEG2
TNEG3
TPOS0
TPOS1
TPOS2
TPOS3
TSER0
TSER1
TSER2
TSER3
TSIG0
TSIG1
TSIG2
TSIG3
TSSYNC0
TSSYNC1
TSSYNC2
TSSYNC3
TSYNC0
84 of 110
CONTROL
BIT
TYPE DESCRIPTION
0 = RSYNC1 an
input
1 = RSYNC1 an
output
I/O
0 = RSYNC2 an
input
1 = RSYNC2 an
output
I/O
0 = RSYNC3 an
input
1 = RSYNC3 an
output
I
I
I
I
I
I
I
I
I
O
O
O
O
O
O
O
O
I
I
I
I
I
I
I
I
I
I
I
I
I/O
DS21FT44/DS21FF44
MCM
LEAD
(DIE1)
-
MCM
LEAD
(DIE2)
MCM
LEAD
(DIE3)
MCM
LEAD
(DIE4)
SCAN
REGIST
ER BIT
63
DS21Q42
DIE
SYMBOL
TSYNC0.cntl
F4
-
W5
W13
F18
28
29
TSYNC1
TSYNC1.cntl
E7
-
T5
U16
C15
122
123
TSYNC2
TSYNC2.cntl
A4
-
M5
N16
D12
96
97
TSYNC3
TSYNC3.cntl
B5
E2
E5
B8
C7
E4
D2
E9
A6
D5
Y16
M4
T2
Y5
W3
K3
U7
P2
U3
K4
U8
Y16
T4
Y9
U12
R17
V19
T12
L16
U4
R16
Y20
Y16
E13
N18
E20
C14
D17
F16
B11
J20
A11
D19
Y16
85
52
18
120
20
*TSYSCLK0
*TSYSCLK1
*TSYSCLK2
*TSYSCLK3
VDD
VDD
VDD
VSS
VSS
VSS
WR*/(R/W*)
* NOTE: RSYSCLKn and TSYSCLKn are tied together.
85 of 110
CONTROL
BIT
TYPE DESCRIPTION
0 = TSYNC0 an
input
1 = TSYNC0 an
output
I/O
0 = TSYNC1 an
input
1 = TSYNC1 an
output
I/O
0 = TSYNC2 an
input
1 = TSYNC2 an
output
I/O
0 = TSYNC3 an
input
1 = TSYNC3 an
output
I
I
I
I
I
DS21FT44/DS21FF44
22.
TIMING DIAGRAMS
RECEIVE SIDE TIMING Figure 22-1
14
FRAME#
RSYNC1/
RFSYNC
15 16 1
2
3
4
5
6
7
8
9
10
11
12 13
14
15 16 1
2
3
4
5
6
RSYNC 2
RLCLK
3
4
RLINK
Notes:
1. RSYNC in the frame mode (RCR1.6 = 0)
2. RSYNC in the multiframe mode (RCR1.6 = 1)
3. RLCLK is programmed to output just the Sa4 bit
4. RLINK will always output all five Sa bits as well as the rest of the receive data stream
5. This diagram assumes the CAS MF begins with the FAS word
RECEIVE SIDE BOUNDARY TIMING (with elastic store disabled) Figure 22-2
RCLK
CHANNEL 1
RPOS, RNEG 1
LSB Si
CHANNEL 2
LSB
CHANNEL 2
1
A Sa4 Sa5 Sa6 Sa7 Sa8 MSB
CHANNEL 32
CHANNEL 1
RSER MSB
LSB Si
1
A
Sa4 Sa5 Sa6 Sa7 Sa8 MSB
RSYNC / RFSYNC
CHANNEL 32
B
A
RSIG
CHANNEL 1
C
Sa5
D
CHANNEL 2
Note 5
RCHCLK
RCHBLK
2
RLINK
Sa4 Sa5 Sa6 Sa7 Sa8
RLCLK3
Notes:
1. There is a 6 RCLK delay from RPOS, RNEG to RSER
2. RCHBLK is programmed to block channel 2
3. RLINK is programmed to output the Sa4 bit
4. Shown is a non-align frame boundary
5. RSIG normally contains the CAS multiframe alignment nibble (0000) in Channel 1
86 of 110
DS21FT44/DS21FF44
RECEIVE SIDE 1.544 MHz BOUNDARY TIMING (with elastic store enabled)
Figure 22-3
RSYSCLK
RSER1
CHANNEL 23/31
CHANNEL 24/32
CHANNEL 1/2
LSB MSB
LSB
F
MSB
RSYNC2/ RMSYNC
RSYNC3
RCHCLK
RCHBLK4
Notes:
1. Data from the E1 channels 1, 5, 9, 13, 17, 21, 25, and 29 is dropped (channel 2 from the E1 link is
mapped to channel 1 of the T1 link, etc.) and the F-bit position is added (forced to one)
2. RSYNC is in the output mode (RCR1.5 = 0)
3. RSYNC is in the input mode (RCR1.5 = 1)
4. RCHBLK is programmed to block channel 24
RECEIVE SIDE 2.048 MHz BOUNDARY TIMING (with elastic store enabled)
Figure 22-4
RSYSCLK
CHANNEL 31
CHANNEL 32
RSER
LSB
CHANNEL 1
LSB MSB
MSB
1
RSYNC / RMSYNC
RSYNC2
CHANNEL 31
RSIG
A
B
CHANNEL 32
C
D
A
B
CHANNEL 1
C
D
Note 4
RCHCLK
RCHBLK 3
Notes:
1. RSYNC is in the output mode (RCR1.5 = 0)
2. RSYNC is in the input mode (RCR1.5 = 1)
3. RCHBLK is programmed to block channel 1
4. RSIG normally contains the CAS multiframe alignment nibble (0000) in Channel 1
87 of 110
DS21FT44/DS21FF44
RECEIVE SIDE INTERLEAVED BUS OPERATION BYTE MODE TIMING Figure
22-5
RSYNC
1
RSER
FR1 CH32
FR0 CH1
FR1 CH1
FR0 CH2
FR1 CH2
FR1 CH32
FR0 CH1
FR1 CH1
FR0 CH2
FR1 CH2
1
RSIG
2
RSER
FR2 CH32 FR3 CH32 FR0 CH1
FR1 CH1
FR2 CH1
FR3 CH1
FR0 CH2
FR1 CH2
FR2 CH2
FR3 CH2
FR2 CH32 FR3 CH32 FR0 CH1
FR1 CH1
FR2 CH1
FR3 CH1
FR0 CH2
FR1 CH2
FR2 CH2
FR3 CH2
2
RSIG
BIT DETAIL
SYSCLK
3
RSYNC
FRAMER 3, CHANNEL 32
RSER
FRAMER 3, CHANNEL 32
RSIG
A
B
C/A
FRAMER 1, CHANNEL 1
FRAMER 0, CHANNEL 1
LSB MSB
LSB MSB
FRAMER 1, CHANNEL 1
FRAMER 0, CHANNEL 1
D/B
A
B
C/D
LSB
D/B
Notes:
1. 4.096 MHz bus configuration.
2. 8.192 MHz bus configuration.
3. RSYNC is in the input mode (RCR1.5 = 1).
88 of 110
A
B
C/D
D/B
DS21FT44/DS21FF44
RECEIVE SIDE INTERLEAVED BUS OPERATION FRAME MODE TIMING
Figure 22-6
RSYNC
1
RSER
1
RSIG
2
RSER
2
RSIG
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32 FR3 CH1-32 FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR2 CH1-32 FR3 CH1-32 FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
BIT DETAIL
SYSCLK
3
RSYNC
RSER
FRAMER 3, CHANNEL 32
LSB MSB
FRAMER 3, CHANNEL 32
RSIG
A
B
C/A
FRAMER 0, CHANNEL 2
FRAMER 0, CHANNEL 1
LSB MSB
FRAMER 0, CHANNEL 2
FRAMER 0, CHANNEL 1
A
D/B
B
C/D
LSB
D/B
A
B
C/D
2
3
4
D/B
Notes:
1. 4.096 MHz bus configuration.
2. 8.192 MHz bus configuration.
3. RSYNC is in the input mode (RCR1.5 = 1).
TRANSMIT SIDE TIMING Figure 22-7
FRAME#
14
15 16 1
2
3
4
5
6
7
8
9
10
11
12 13
14
15 16
1
TSYNC
2
TSYNC
TLCLK
TLINK
3
3
Notes:
1. TSYNC in the frame mode (TCR1.1 = 0)
2. TSYNC in the multiframe mode (TCR1.1 = 1)
3. TLINK is programmed to source just the Sa4 bit
4. This diagram assumes both the CAS MF and the CRC4 begin with the align frame
89 of 110
1
5
6
DS21FT44/DS21FF44
TRANSMIT SIDE BOUNDARY TIMING (with elastic store disabled) Figure 22-8
TCLK
CHANNEL 1
TSER
LSB
Si
1
A
Sa4
Sa5
CHANNEL 2
Sa6
Sa7
Sa8
CHANNEL 32
TPOS, TNEG1
MSB
MSB
LSB
MSB
CHANNEL 1
LSB
Si
1
A
Sa4
Sa5
Sa6
Sa7 Sa8
MSB
2
TSYNC
TSYNC3
CHANNEL 1
TSIG
B
C
CHANNEL 2
A
D
B
C
D
Note 6
TCHCLK
TCHBLK
TLCLK
TLINK
4
5
5
Don't Care
Don't Care
Notes:
1. There is a 5 TCLK delay from TSER to TPOS and TNEG
2. TSYNC is in the input mode (TCR1.0 = 0)
3. TSYNC is in the output mode (TCR1.0 = 1)
4. TCHBLK is programmed to block channel 2
5. TLINK is programmed to source the Sa4 bits
6. The signaling data at TSIG during channel 1 is normally overwritten in the transmit formatter with
the CAS multiframe alignment nibble (0000)
7. Shown is a non-align frame boundary
TRANSMIT SIDE 1.544 MHz BOUNDARY TIMING (with elastic store enabled)
Figure 22-9
TSYSCLK
CHANNEL 23
TSER
CHANNEL 24
CHANNEL 1
MSB
LSB
LSB MSB
F-Bit
TSSYNC
TCHCLK
1
TCHBLK
Notes:
1. TCHBLK is programmed to block channel 23
2. The F-bit position is ignored by the DS2154
90 of 110
DS21FT44/DS21FF44
TRANSMIT SIDE 2.048 MHz BOUNDARY TIMING (with elastic store enabled)
Figure 22-10
TSYSCLK
CHANNEL 31
CHANNEL 32
TSER
CHANNEL 1
LSB
LSB MSB
MSB
TSSYNC
CHANNEL 31
TSIG
A
B
CHANNEL 32
C
A
D
B
CHANNEL 1
C
D
A
TCHCLK
1
TCHBLK
Notes:
1. TCHBLK is programmed to block channel 31
G.802 TIMING Figure 22-11
TIMESLOT # 30 31 0 1 2 3 4 5 6 7 8 910 111213141516 17 18 19202122232425262728293031 0 1 2 3 4
RSYNC/TSYNC
RCHCLK/TCHCLK
RCHBLK/TCHBLK1
Notes:
1. RCHBLK or TCHBLK is programmed to pulse high during timeslots
1 to 15, 17 to 25, and during bit 1 of timeslot 26
detail
RCLK / RSYSCLK
TCLK / TSYSCLK
Timeslot 25
RSER/TSER
Timeslot 26
LSB
RCHCLK/TCHCLK
RCHBLK/TCHBLK
91 of 110
MSB
DS21FT44/DS21FF44
TRANSMIT SIDE INTERLEAVED BUS OPERATION BYTE MODE TIMING
Figure 22-12
TSSYNC
1
TSER
1
TSIG
2
TSER
FR1 CH32
FR0 CH1
FR1 CH1
FR0 CH2
FR1 CH2
FR1 CH32
FR0 CH1
FR1 CH1
FR0 CH2
FR1 CH2
FR2 CH32 FR3 CH32 FR0 CH1
FR1 CH1
FR2 CH1
FR3 CH1
FR0 CH2
FR1 CH2
FR2 CH2
FR3 CH2
FR2 CH32 FR3 CH32 FR0 CH1
FR1 CH1
FR2 CH1
FR3 CH1
FR0 CH2
FR1 CH2
FR2 CH2
FR3 CH2
2
TSIG
BIT DETAIL
SYSCLK
TSSYNC
FRAMER 3, CHANNEL 32
TSER
FRAMER 3, CHANNEL 32
TSIG
A
B
C/A
D/B
FRAMER 1, CHANNEL 1
FRAMER 0, CHANNEL 1
LSB MSB
LSB MSB
FRAMER 1, CHANNEL 1
FRAMER 0, CHANNEL 1
A
B
C/D
LSB
D/B
Notes:
1. 4.096 MHz bus configuration.
2. 8.192 MHz bus configuration.
92 of 110
A
B
C/D
D/B
DS21FT44/DS21FF44
TRANSMIT SIDE INTERLEAVED BUS OPERATION FRAME MODE TIMING
Figure 22-13
TSSYNC
1
TSER
1
TSIG
2
TSER
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32 FR3 CH1-32 FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR2 CH1-32 FR3 CH1-32 FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
FR0 CH1-32
FR1 CH1-32
FR2 CH1-32
FR3 CH1-32
2
TSIG
BIT DETAIL
SYSCLK
TSSYNC
FRAMER 3, CHANNEL 32
TSER
FRAMER 3, CHANNEL 32
TSIG
A
B
C/A
D/B
FRAMER 0, CHANNEL 2
FRAMER 0, CHANNEL 1
LSB MSB
LSB MSB
FRAMER 0, CHANNEL 2
FRAMER 0, CHANNEL 1
A
B
C/D
LSB
D/B
Notes:
1. 4.096 MHz bus configuration.
2. 8.192 MHz bus configuration.
93 of 110
A
B
C/D
D/B
DS21FT44/DS21FF44
DS21Q44 FRAMER SYNCHRONIZATION FLOWCHART Figure 22-14
Power Up
RLOS = 1
FAS Search
FASSA = 1
RLOS = 1
FAS Sync
Criteria Met
FASSA = 0
Resync if
RCR1.0 = 0
Increment CRC4
Sync Counter;
CRC4SA = 0
8ms
Time
Out
CRC4 Multiframe Search
(if enabled via CCR1.0)
CRC4SA = 1
CRC4 Sync Criteria
Met; CRC4SA = 0;
Reset CRC4
Sync Counter
Set FASRC
(RIR.1)
CRC4 Resync
Criteria Met
(RIR.2)
CAS Resync
Criteria Met;
Set CASRC
(RIR.0)
FAS Resync
Criteria Met
Check for FAS
Framing Error
(depends on RCR1.2)
Check for >=915
Out of 1000
CRC4 Word Errors
If CRC4 is on
(CCR1.0 = 1)
Check for CAS
MF Word Error
If CAS is on
(CCR1.3 = 0)
94 of 110
CAS Multiframe Search
(if enabled via CCR1.3)
CASSA = 1
Sync Declared
RLOS = 0
CAS Sync
Criteria Met
CASSA = 0
DS21FT44/DS21FF44
DS21Q44 TRANSMIT DATA FLOW Figure 22-15
TSER
&
TDATA
HDLC
ENGINE
TCBR1/2/3/4
TSIG
0
RSER
(note #1)
TLINK
1
Hardware
Signaling
Insertion
CCR3.5
CCR3.2
TNAF.0-4
0
Sa Data Source
MUX
(TDC1)
1
0
1
DS0 Data
Source MUX
(TDC1/2)
TAF
TNAF.5-7
0
TAF/TNAF Bit
MUX
TC1 to TC32
1
0
1
Per-Channel Code
Generation
(TCC1/2/3/4)
0
1
Timeslot 0
Pass-Through
(TCR1.6)
1
0
Si Bit Insertion
Control
(TCR1.3)
Receive Side
CRC4 Error
Detector
CRC4 Multiframe
Alignment Word
Generation (CCR.4)
1
0
E-Bit Generation
(TCR2.1)
0
1
Sa Bit Insertion
Control (TCR2.3
thru TCR2.7)
TSiAF
TSiNAF
TIDR
TRA
Auto Remote Alarm
Generation (CCR2.4)
0
TSa4 to TSa8
1
TIRFunction Select
(CCR3.5)
0
1
Sa Bit Insertion
Control Register
(TSaCR)
AIS
Generation
TS1 to TS16
0
1
Idle Code / Channel
Insertion Control via
TIR1/2/3/4
0
1
Transmit Signaling
All Ones
(TCR1.2)
TCBR1/2/3/4
0
1
Signaling Bit
Insertion Control
CCR3.6
TCR1.5
Code Word
Generation
0
1
CRC4 Enable
(CCR1.4)
KEY:
= Register
AIS
Generation
DS0 Monitor
= Device Pin
0
1
Transmit Unframed All
Ones (TCR1.4) or
Auto AIS (CCR2.5)
= Selector
NOTES:
1. TCLK should be tied to RCLK and TSYNC should be tied to RFSYNC for
data to be properly sourced from RSER.
2. Auto Remote Alarm if enabled will only overwrite bit 3 of timeslot 0 in the
Not Align Frames if the alarm needs to be sent.
95 of 110
TPOS,
TNEG
DS21FT44/DS21FF44
23.
OPERATING PARAMETERS
ABSOLUTE MAXIMUM RATINGS*
Voltage on Any Non-Supply Pin Relative to Ground
Supply Voltage
Operating Temperature for DS21Q44T
Operating Temperature for DS21Q44TN
Storage Temperature
Soldering Temperature
–1.0V to +5.5V
–.3V to +3.63V
0ºC to 70ºC
–40ºC to +85ºC
–55ºC to +125ºC
See J-STD-020A
* This is a stress rating only and functional operation of the device at these or any other conditions above
those indicated in the operation sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods of time may affect reliability.
RECOMMENDED DC OPERATING CONDITIONS
(0ºC to 70ºC for DS21FF44/DS21FT44
-40ºC to +85ºC for DS21FF44N/DS21FT44N)
PARAMETER
Logic 1
Logic 0
Supply
SYMBOL
VIH
VIL
VDD
MIN
2.0
–0.3
2.97
TYP
MAX
5.5
+0.8
3.63
UNITS
V
V
V
CAPACITANCE
PARAMETER
Input Capacitance
Output Capacitance
NOTES
(tA =25ºC)
SYMBOL
CIN
COUT
MIN
TYP
5
7
MAX
UNITS
pF
pF
NOTES
DC CHARACTERISTICS
(0ºC to 70ºC; VDD = 2.97 to 3.63V for DS21FF44/DS21FT44
-40ºC to +85ºC; VDD = 2.97 to 3.63V for DS21FF44N/DS21FT44N)
PARAMETER
Supply Current @ 3.3V
(DS21FT44)
Supply Current @ 3.3V
(DS21FF44)
Input Leakage
Output Leakage
Output Current (2.4V)
Output Current (0.4V)
SYMBOL
IDD
MIN
IDD
IIL
ILO
IOH
IOL
TYP
225
MAX
300
–1.0
+1.0
1.0
–1.0
+4.0
NOTES:
1. TCLK=RCLK=TSYSCLK=RSYSCLK=2.048 MHz; outputs open circuited.
2. 0.0V < V IN < V DD .
3. Applied to INT* when 3–stated.
96 of 110
UNITS
mA
NOTES
1
mA
1
µA
µA
mA
mA
2
3
DS21FT44/DS21FF44
AC CHARACTERISTICS – MULTIPLEXED
PARALLEL PORT (MUX=1)
(0ºC to 70ºC; VDD = 2.97 to 3.63V for DS21FF44/DS21FT44;
–40ºC to +85ºC; VDD = 2.97 to 3.63V for DS21FF44N/DS21FT44N)
PARAMETER
SYMBOL
Cycle Time
t CYC
Pulse Width, DS low or
PW EL
RD* high
Pulse Width, DS high or
PW EH
RD* low
Input Rise/Fall times
tR,tF
R/W* Hold Time
t RWH
R/W* Set Up time
t RWS
before DS high
CS*, FSO or FS1 Set
t CS
Up time before DS,
WR* or RD* active
CS*, FSO or FS1 Hold
t CH
time
Read Data Hold time
t DHR
Write Data Hold time
t DHW
Muxed Address valid to
t ASL
AS or ALE fall
Muxed Address Hold
t AHL
time
Delay time DS, WR* or
t ASD
RD* to AS or ALE rise
Pulse Width AS or ALE
PW ASH
high
Delay time, AS or ALE
t ASED
to DS, WR* or RD*
Output Data Delay time
t DDR
from DS or RD*
Data Set Up time
t DSW
See Figures 23-1 to 23-3 for details
MIN
200
100
TYP
MAX
100
UNITS
ns
ns
ns
20
10
50
ns
ns
ns
20
ns
0
ns
10
0
15
50
ns
ns
ns
10
ns
20
ns
30
ns
10
ns
20
80
50
ns
ns
97 of 110
NOTES
DS21FT44/DS21FF44
AC CHARACTERISTICS – NON–MULTIPLEXED
PARALLEL PORT (MUX=0 )
(0ºC to 70ºC; VDD = 2.97 to 3.63V for DS21FF44/DS21FT44;
–40ºC to +85ºC; VDD = 2.97 to 3.63V for DS21FF44N/DS21FTN44)
PARAMETER
SYMBOL
Set Up Time for A0 to
t1
A7, FS0 or FS1 Valid to
CS* Active
Set Up Time for CS*
t2
Active to either RD*,
WR*, or DS* Active
Delay Time from either
t3
RD* or DS* Active to
Data Valid
Hold Time from either
t4
RD*, WR*, or DS*
Inactive to CS* Inactive
Hold Time from CS*
t5
Inactive to Data Bus 3–
state
Wait Time from either
t6
WR* or DS* Active to
Latch Data
Data Set Up Time to
t7
either WR* or DS*
Inactive
Data Hold Time from
t8
either WR* or DS*
Inactive
Address Hold from
t9
either WR* or DS*
inactive
See Figures 23–4 to 23–7 for details.
MIN
0
TYP
MAX
0
UNITS
ns
ns
75
0
ns
ns
5
20
ns
75
ns
10
ns
10
ns
10
ns
98 of 110
NOTES
DS21FT44/DS21FF44
AC CHARACTERISTICS – RECEIVE SIDE
(0ºC to 70ºC; VDD = 2.97 to 3.63V for DS21FF44/DS21FT44
–40ºC to +85ºC; VDD = 2.97 to 3.63V for DS21FF44N/DS21FT44N)
PARAMETER
RCLK Period
RCLK Pulse Width
RSYSCLK Period
RSYSCLK Pulse Width
SYMBOL
t CP
t CH
t CL
t SP
t SP
t SH t SL
RSYNC Set Up to
t SU
RSYSCLK Falling
RSYNC Pulse Width
t PW
RPOS/RNEG Set UP to
t SU
RCLK Falling
RPOS/RNEG Hold From
t HD
RCLK Falling
RSYSCLK/RCLKI Rise
tR,tF
and Fall Times
Delay RCLK to RSER,
t D1
RSIG, RLINK Valid
Delay RCLK to RCHCLK,
t D2
RSYNC, RCHBLK,
RFSYNC, RLCLK
Delay RSYSCLK to
t D3
RSER, RSIG Valid
Delay RSYSCLK to
t D4
RCHCLK, RCHBLK,
RMSYNC, RSYNC
See Figures 23-8 to 23-10 for details.
MIN
75
75
122
122
50
50
20
TYP
488
MAX
648
488
t SH –5
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
50
20
ns
ns
20
ns
NOTES:
1. RSYSCLK = 1.544 MHz.
2. RSYSCLK = 2.048 MHz.
99 of 110
25
ns
50
ns
50
ns
50
ns
50
ns
NOTES
1
2
DS21FT44/DS21FF44
AC CHARACTERISTICS – TRANSMIT SIDE
(0ºC to 70ºC; VDD = 2.97 to 3.63V for DS21FF44/DS21FT44
–40ºC to +85ºC; ; VDD = 2.97 to 3.63V for DS21FF44N/DS21FT44N)
PARAMETER
TCLK Period
TCLK Pulse Width
TCLKI Pulse Width
TSYSCLK Period
TSYSCLK Pulse Width
SYMBOL
t CP
t CH
t CL
t LH
t LL
t SP
t SP
t SH
t SL
t SU
TSYNC or TSSYNC Set
Up to TCLK or TSYSCLK
falling
TSYNC or TSSYNC Pulse
t PW
Width
TSER, TSIG, TLINK Set
t SU
Up to TCLK, TSYSCLK
Falling
TSER, TSIG, TLINK Hold
t HD
from TCLK, TSYSCLK
Falling
TCLK or TSYSCLK Rise
tR,tF
and Fall Times
Delay TCLK to TPOS,
t DD
TNEG Valid
Delay TCLK to TCHBLK,
t D2
TCHBLK, TSYNC,
TLCLK
Delay TSYSCLK to
t D3
TCHCLK, TCHBLK
See Figures 23–11 to 23–13 for details.
MIN
TYP
488
75
75
75
75
122
122
50
50
20
MAX
648
448
t CH –5
or
t SH –5
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
50
ns
20
ns
20
ns
NOTES:
1. TSYSCLK = 1.544 MHz.
2. TSYSCLK = 2.048 MHz.
100 of 110
25
ns
50
ns
50
ns
75
ns
NOTES
1
2
DS21FT44/DS21FF44
INTEL BUS READ AC TIMING (BTS=0 / MUX = 1) Figure 23-1
t CYC
ALE
PWASH
t ASD
WR*
t ASD
RD*
PWEL
t ASED
PWEH
t CH
t CS
CS*
t ASL
t DHR
t DDR
AD0-AD7
t AHL
INTEL BUS WRITE TIMING (BTS=0 / MUX=1) Figure 23-2
t CYC
ALE
PWASH
t ASD
RD*
WR*
t ASD
PWEL
t ASED
PWEH
t CH
t CS
CS*
t ASL
t DHW
AD0-AD7
t AHL
t DSW
101 of 110
DS21FT44/DS21FF44
MOTOROLA BUS AC TIMING (BTS = 1 / MUX = 1) Figure 23-3
PWASH
AS
t ASD
DS
PWEH
t ASED
PWEL
t CYC
t RWS
R/W*
t DDR
t ASL
AD0-AD7
(read)
t RWH
t AHL
t DHR
t CH
t CS
CS*
t DSW
t ASL
AD0-AD7
(write)
t DHW
t AHL
INTEL BUS READ AC TIMING (BTS=0 / MUX=0) Figure 23-4
A0 to A7,
FS0, FS1
Address Valid
Data Valid
D0 to D7
WR*
5ns min. / 20ns max.
t1
CS*
0ns min.
RD*
t5
0ns min.
t2
t3
t4
75ns max.
102 of 110
0ns min.
DS21FT44/DS21FF44
INTEL BUS WRITE AC TIMING (BTS=0 / MUX=0) Figure 23-5
A0 to A7,
FS0, FS1
Address Valid
D0 to D7
t7
RD*
t8
10ns 10ns
min. min.
t1
0ns min.
CS*
0ns min.
t2
t6
t4
0ns min.
75ns min.
WR*
MOTOROLA BUS READ AC TIMING (BTS=1 / MUX=0) Figure 23-6
A0 to A7,
FS0, FS1
Address Valid
Data Valid
D0 to D7
5ns min. / 20ns max.
R/W*
t5
t1
0ns min.
CS*
0ns min.
t2
t3
t4
0ns min.
75ns max.
DS*
t2
0ns min.
DS
1
t4
t3
0ns min.
75ns max.
Notes:
1. The signal DS is active high when emulating the DS21Q43 (FMS = 1).
103 of 110
DS21FT44/DS21FF44
MOTOROLA BUS WRITE AC TIMING (BTS=1 / MUX=0) Figure 23-7
A0 to A7,
FS0, FS1
Address Valid
D0 to D7
R/W*
10ns
min.
t1
CS*
0ns min.
t2
t4
t6
DS*
t2
t6
0ns min.
1
t8
10ns
min.
0ns min.
75ns min.
DS
t7
75ns min.
Notes:
1. The signal DS is active high when emulating the DS21Q43 (FMS = 1)
.
104 of 110
0ns min.
DS21FT44/DS21FF44
RECEIVE SIDE AC TIMING Figure 23-8
RCLK
t D1
MSB of
Channel 1
RSER / RSIG
t D2
RCHCLK
t D2
RCHBLK
t
D2
RFSYNC / RMSYNC
t D2
RSYNC1
t D2
2
RLCLK
t D1
RLINK
Sa4 to Sa8
Bit Position
Notes:
1. RSYNC is in the output mode (RCR1.5 = 0).
2. RLCLK will only pulse high during Sa bit locations as defined in RCR2; no relationship
between RLCLK and RSYNC or RFSYNC is implied.
105 of 110
DS21FT44/DS21FF44
RECEIVE SYSTEM SIDE AC TIMING Figure 23-9
tSL
tF
tR
tSH
RSYSCLK
tSP
tD3
MSB of
Channel 1
RSER / RSIG
tD4
RCHCLK
tD4
RCHBLK
t
D4
RMSYNC
t D4
1
RSYNC
tHD
tSU
RSYNC2
Notes:
1. RSYNC is in the output mode (RCR1.5 = 0)
2. RSYNC is in the input mode (RCR1.5 = 1)
106 of 110
DS21FT44/DS21FF44
RECEIVE LINE INTERFACE AC TIMING Figure 23-10
t CL
tF
tR
t CH
RCLK
t CP
t SU
RPOS, RNEG
t HD
TRANSMIT SIDE AC TIMING Figure 23-11
t CP
t CL
tF
tR
t CH
TCLK
t SU
TSER / TSIG
t HD
t D2
TCHCLK
t D2
TCHBLK
t D2
TSYNC1
t SU
t HD
TSYNC2
5
TLCLK
t D2
t HD
TLINK
t SU
Notes:
1. TSYNC is in the output mode (TCR1.0 = 1).
2. TSYNC is in the input mode (TCR1.0 = 0).
3. TSER is sampled on the falling edge of TCLK when the transmit side elastic store is disabled.
4. TCHCLK and TCHBLK are synchronous with TCLK when the transmit side elastic store is disabled.
5. TLINK is only sampled during Sa bit locations as defined in TCR2; no relationship between
TLCLK/TLINK and TSYNC is implied.
107 of 110
DS21FT44/DS21FF44
TRANSMIT SYSTEM SIDE AC TIMING Figure 23-12
tSP
tSL
tF
tR
tSH
TSYSCLK
tSU
TSER
t D3
tHD
TCHCLK
tD3
TCHBLK
tSU
tHD
TSSYNC
Notes:
1. TSER is only sampled on the falling edge of TSYSCLK when the transmit side elastic store is enabled.
2. TCHCLK and TCHBLK are synchronous with TSYSCLK when the transmit side elastic store is enabled.
108 of 110
DS21FT44/DS21FF44
TRANSMIT LINE INTERFACE SIDE AC TIMING Figure 23-13
t CP
tR
tF
t CL
TCLK
TPOS, TNEG
t DD
24.
MCM PACKAGE DIMENSIONS
109 of 110
t CH
DS21FT44/DS21FF44
POWER SUPPLY DE-COUPLING
In a typical PCB layout for the MCM, all of the VDD pins will connect to a common power plane and all
the VSS lines will connect to a common ground plane. The recommended method for de-coupling is
shown below in both schematic and pictorial form. As shown in the pictorial, the capacitors should be
symmetrically located about the device. Figure 24-1 uses standard capacitors, two .47 uf ceramics and
two .01uf ceramics. Since VDD and VSS signals will typically pass vertically to the power and ground
planes of a PCB, the de-coupling caps must be placed as close to the DS21Fx4y as possible and routed
vertically to power and ground planes.
De-coupling scheme using standard tantalum caps. Figure 24-1
VDD
.47
.01
VDD
DS21Fx4y
.47
.01
.47
.01
110 of 110
.47
DS21Fx4y
.01