13
COMMERCIAL TEMPERATURE RANGE
IDT7290820 5V TIME SLOT INTERCHANGE
DIGITAL SWITCH 2,048 x 2,048
0123 456 78 910111213141516
ST-BUS
Frame
CLK
Offset Value
FE Input
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
GCI Frame
CLK
Offset Value
FE Input
(FD[10:0] = 06H)
(FD11 = 0, sample at CLK LOW phase)
(FD[10:0] = 09
H)
(FD11 = 1, sample at CLK HIGH phase)
5713 drw07
TABLE 10 FRAME ALIGNMENT REGISTER (FAR) BITS
Figure 4. Example for Frame Alignment Measurement
Bit Name Description
15-13 Unused Must be zero for normal operation.
12 CFE When CFE = 1, the frame evaluation is completed and bits FD10 to FD0 bits contains a valid frame alignment
(Complete Frame Evaluation) offset. This bit is reset to zero, when SFE bit in the IMS register is changed from 1 to 0.
11 FD11 The falling edge of FE (or rising edge for GCI mode) is sampled during the CLK-high phase (FD11 = 1)
(Frame Delay Bit 11) or during the CLK-low phase (FD11 = 0). This bit allows the measurement resolution to ½ CLK cycle.
10-0 FD10-0 The binary value expressed in these bits refers to the measured input offset value. These bits are rest to
(Frame Delay Bits) zero when the
SFE bit of the IMS register changes from 1 to 0. (FD10 – MSB, FD0 – LSB)
Read/Write Address: 02
H,
Reset Value: 0000
H.
1514131211109876543210
0 0 0 CFE FD11 FD10 FD9 FD8 FD7 FD6 FD5 FD4 FD3 FD2 FD1 FD0