Internal Buffer Ram Operation In 6-Byte Transmission (In Automatic Transmission Mode) - NEC 78K0 User Manual

CHAPTER 17 SERIAL INTERFACE CSIA0
In 6-byte transmission (ATM0 = 0, RXEA0 = 0, TXEA0 = 1, ATE0 = 1) in automatic transmission mode,
internal buffer RAM operates as follows.
(i) Starting transmission (see Figure 17-18 (a).)
When bit 0 (ATSTA0) of serial trigger register 0 (CSIT0) is set to 1, transmit data 1 (T1) is transferred
from the internal buffer RAM to SIOA0. When transmission of the first byte is completed, automatic
data transfer address count register 0 (ADTC0) is incremented.
transferred from the internal buffer RAM to SIOA0.
(ii) 4th byte transmission point (see Figure 17-18 (b).)
Transmission of the third byte is completed, and transmit data 4 (T4) is transferred from the internal
buffer RAM to SIOA0. When transmission of the fourth byte is completed, ADTC0 is incremented.
(iii) Completion of transmission (see Figure 17-18 (c).)
When transmission of the sixth byte is completed, the interrupt request flag (ACSIIF) is set (INTACSI
generation). Bit 0 (TSF0) of serial status register 0 (CSIS0) is cleared.
Figure 17-18. Internal Buffer RAM Operation in 6-Byte Transmission
(in Automatic Transmission Mode) (1/2)
FA1FH
FA05H Transmit data 6 (T6)
Transmit data 5 (T5)
Transmit data 4 (T4)
Transmit data 3 (T3)
Transmit data 2 (T2)
FA00H Transmit data 1 (T1)
(a) Starting transmission
*
+1
User's Manual U15947EJ2V0UD
Then transmit data 2 (T2) is
SIOA0
5 ADTP0
0 ADTC0
0 ACSIIF
405