NEC PD78F9488 - Manual (Page 241)

CHAPTER 12 SERIAL INTERFACE 1A0
User’s Manual U15331EJ4V1UD
241
Figure 12-11. Basic Transmit Mode Flowchart
Remark ADTP0: Automatic data transmit/receive address pointer 0
ADTI0: Automatic data transmit/receive interval specification register 0
SIO1A0: Serial I/O shift register 1A0
TRF0: Bit 3 of automatic data transmit/receive control register 0 (ADTC0)
Start
Write transmit data
in buffer RAM
Set ADTP0 to the value (pointer
value) obtained by subtracting 1
from the number of transmit
data bytes
Set the transmission/reception
operation interval time in ADTI0
Write any data to SIO1A0
(Start trigger)
Write transmit data from
buffer RAM to SIO1A0
Transmission operation
Pointer value = 0
No
TRF0 = 0
No
End
Yes
Yes
Decrement pointer value
Software execution
Hardware execution
Software execution