23.2MASTER 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

MSK

Shift

Out

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.

End of Transfer

CP3BT26

Data Out

MSB

MSB - 1

MSB - 2

Bit 1

 

Sample

 

 

 

 

Point

 

 

 

Data In

MSB

MSB - 1

MSB - 2

Bit 1

Figure 85. Normal Mode (SCIDL = 0)

MSK

 

 

 

 

 

Shift

 

 

 

 

Out

 

 

 

Data Out

MSB

MSB - 1

MSB - 2

Bit 1

 

Sample

 

 

 

 

Point

 

 

 

Data In

MSB

MSB - 1

MSB - 2

Bit 1

Figure 86. Normal Mode (SCIDL = 1)

MSK

 

 

 

 

 

Shift

 

 

 

 

Out

 

 

 

Data Out

MSB

MSB - 1

MSB - 2

Bit 1

 

Sample

 

 

 

 

Point

 

 

 

Data In

MSB

MSB - 1

MSB - 2

Bit 1

Figure 87. Alternate Mode (SCIDL = 0)

MSK

 

 

 

 

 

 

Shift

 

 

 

 

Out

 

 

Data Out

MSB

MSB - 1

MSB - 2

Bit 1

 

Sample

 

 

 

 

Point

 

 

 

Data In

MSB

MSB - 1

MSB - 2

Bit 1

Figure 88. Alternate Mode (SCIDL = 1)

Bit 0

(LSB)

Bit 0

(LSB)

DS069

End of Transfer

Bit 0

(LSB)

Bit 0

(LSB)

DS070

End of Transfer

Bit 0

(LSB)

Bit 0

(LSB)

DS071

End of Transfer

Bit 0

(LSB)

Bit 0

(LSB)

DS072

177

www.national.com

Page 177
Image 177
National CP3BT26 manual Master Mode, Normal Mode Scidl =