NEC 78014Y Series User Manual page 303

8-bit single-chip microcontrollers
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(6) Address match detection method
In the SBI mode, a particular slave device can be selected by sending a slave address from the master device.
Address match detection is automatically executed by hardware. With the slave address register (SVA), and
if the wake-up function specification bit (WUP) = 1, CSIIF0 is set only when the selve address transmitted from
the master device matches the value set in SVA.
If bit 5 (SIC) of the interrupt timing specification register (SINT) is set to 1, the wake-up function dose not operate
even with WUP = 1 (an interrupt request signal is generated in detecting a bus release). When the wake-up
function is used, clear SIC to 0.
Cautions 1. Slave selection/non-selection is detected by matching of the slave address received after
(7) Error detection
In the SBI mode, the serial bus SB0 (SB1) status being transmitted is fetched into the destination device, that
is, the serial I/O shift register 0 (SIO0). Thus, transmit errors can be detected in the following ways:
(a) Method of comparing SIO0 data before transmission to that after transmission
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(b) Method of using the slave address register (SVA)
CHAPTER 15 SERIAL INTERFACE CHANNEL 0 ( µ PD78014 Subseries)
bus release (RELD = 1).
For this match detection, match interrupt request (INTCSI0) of the address to be generated
with WUP = 1 is normally used. Thus, execute selection/non-selection detection by slave
address when WUP = 1.
2. When detecting selection/non-selection without the use of interrupt request with WUP = 0,
do so by means of transmission/reception of the command preset by program instead of
using the address match detection method.
In this case, if two data differ from each other, a transmit error is judged to have occurred.
Transmit data is set to both SIO0 and SVA and is transmitted. After termination of transmission, the COI
bit (match signal coming from the address comparator) of the serial operating mode register 0 (CSIM0) is
tested. If it is "1", normal transmission is judged to have been carried out. If it is "0", a transmit error is judged
to have occurred.
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