Panasonic F77G, MN101C77C user manual ACK Bit Reception Timing after Transmission of 8-Bit Data

Models: F77G MN101C77C

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Chapter 12 Serial Interface 3

„Reception of Acknowledgement (ACK) Bit after Data Transmission

This LSI does not contain the function of receiving the acknowledgement (ACK) bit after data transmission. To receive ACK bit after transmitting data, select sc3acks= "0" (No ACK bit) before data transmisison. By transmitting the 8-bit data, an interrupt generates. Then switch the SBT pin function to "port" in the interrupt routine. With the port function, program a clock for ACK reception and read the ACK data.

SDA

SCL

Data transmission period

(Hardware processing period) ACK bit reception period (Software processing period)

1

2

. .

8

ACK/

NACK

 

 

 

 

ACK bit reception clock (generated by switching the pin of software)

Interrupt

Figure 12-3-13 ACK Bit Reception Timing after Transmission of 8-Bit Data

„Transmission of Acknowledgement (ACK) bit after Data Reception

The way of the selection if ACK bit is enabled or not is the same to the way at the transmission. When ACK bit is enabled, ACK bit and clock are output after data (1 to 8 bits) is received. If the reception is to continue, ACK bit outputs "L". And if the reception is to finish, it outputs "H". The SC3ACK0 of the SC3CTR register sets the output ACK bit level.

SDA

Data reception period (Bus release period)

 

 

 

T Tmax=1.2 T

1

2

. .

8

ACK/

NACK

 

 

 

 

SCL

ACK bit transmission clock

Interrupt

Figure 12-3-14 ACK Bit Transmission Timing after Reception of 8-Bit Data

Operation XII - 29

Page 415
Image 415
Panasonic F77G, MN101C77C user manual ACK Bit Reception Timing after Transmission of 8-Bit Data