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2 master mode, Master mode, Cp3 bt26 – National CP3BT26 User Manual

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CP3

BT26

23.2

MASTER MODE

In Master mode, the MSK pin is an output for the shift clock,
MSK. When data is written to the MWDAT register, eight or
sixteen MSK clocks, depending on the mode selected, are

generated to shift the 8 or 16 bits of data, and then MSK
goes idle again. The MSK idle state can be either high or
low, depending on the SCIDL bit.

Figure 85.

Normal Mode (SCIDL = 0)

Figure 86.

Normal Mode (SCIDL = 1)

Figure 87.

Alternate Mode (SCIDL = 0)

Figure 88.

Alternate Mode (SCIDL = 1)

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

MSK

End of Transfer

Sample
Point

Shift
Out

Data Out

MSB

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

Data In

MSB

DS069

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

MSK

End of Transfer

Data Out

MSB

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

Data In

MSB

Sample
Point

Shift
Out

DS070

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

MSK

End of Transfer

Data Out

MSB

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

Data In

MSB

Sample
Point

Shift
Out

DS071

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

MSK

End of Transfer

Sample
Point

Shift
Out

Data Out

MSB

Bit 0

(LSB)

Bit 1

MSB - 2

MSB - 1

Data In

MSB

DS072