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Phantom clock register information, Phantom clock register definition figure 1 – Rainbow Electronics DS1248Y User Manual

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DS1248Y

032697 3/12

PHANTOM CLOCK
REGISTER INFORMATION

The Phantom Clock information is contained in 8 regis-
ters of 8 bits, each of which is sequentially accessed one
bit at a time after the 64–bit pattern recognition se-
quence has been completed. When updating the Phan-
tom Clock registers, each register must be handled in
groups of 8 bits. Writing and reading individual bits with-

in a register could produce erroneous results. These
read/write registers are defined in Figure 2.

Data contained in the Phantom Clock register is in
binary coded decimal format (BCD). Reading and writ-
ing the registers is always accomplished by stepping
through all 8 registers, starting with bit 0 of register 0 and
ending with bit 7 of register 7.

PHANTOM CLOCK REGISTER DEFINITION Figure 1

7

6

5

4

3

2

1

0

1

1

0

0

0

1

0

1

0

0

1

1

1

0

1

0

1

0

1

0

0

0

1

1

0

1

0

1

1

1

0

0

1

1

0

0

0

1

0

1

0

0

1

1

1

0

1

0

1

0

1

0

0

0

1

1

0

1

0

1

1

1

0

0

C5

3A

A3

5C

C5

3A

A3

5C

BYTE 0

BYTE 1

BYTE 2

BYTE 3

BYTE 4

BYTE 5

BYTE 6

BYTE 7

HEX

VALUE

NOTE:

The pattern recognition in Hex is C5, 3A, A3, 5C, C5, 3A, A3, 5C. The odds of this pattern being accidentally dupli-
cated and causing inadvertent entry to the Phantom Clock is less than 1 in 10

19

. This pattern is sent to the Phantom

Clock LSB to MSB.