Operation Modes And Trigger Modes - NEC UPD703116 User Manual

13.5.2 Operation modes and trigger modes

Diverse conversion operations can be specified for A/D converters 0 and 1 by specifying operation modes and
trigger modes. Operation modes and trigger modes are set using the ADSCM00 or ADSCM10 register.
The relationship between operation modes and trigger modes is shown below.
Trigger Mode
AD trigger
AD trigger polling
Timer trigger
External trigger
(1) Trigger modes
The four trigger modes that serve as the start timing of A/D conversion processing are available: A/D trigger
mode, A/D trigger polling mode, timer trigger mode, and external trigger mode.
These trigger modes are set using the ADSCM00 and ADSCM10 registers.
(a) A/D trigger mode
A/D trigger mode, which starts the conversion timing of the analog input set for the ANI0n or ANI1n pin (n
= 0 to 7), is a mode that starts A/D conversion by setting the ADCE0 or ADCE1 bit of the ADSCM00 or
ADSCM10 register to 1. In this mode, it is necessary to set the ADCE0 or ADCE1 bit to 1 as an A/D
conversion restart operation after an INTAD0 or INTAD1 interrupt (ADCS0 or ADCS1 = 0).
(b) A/D trigger polling mode
A/D trigger polling mode, which starts the conversion timing of the analog input set for the ANI0n or
ANI1n pin (n = 0 to 7), is a mode that starts A/D conversion by setting the ADCE0 or ADCE1 bit of the
ADSCM00 or ADSCM10 register to 1. In this mode, it is not necessary to set the ADCE0 or ADCE1 bit to
1 as an A/D conversion restart operation after an INTAD0 or INTAD1 interrupt (ADCS0 or ADCS1 = 1).
The specified analog input is converted serially until the ADCE0 or ADCE1 bit is set to 0. An INTAD0 or
INTAD1 interrupt occurs each time a conversion terminates.
(c) Timer trigger mode
Timer trigger mode, which starts the conversion timing of the analog input set for the ANI0n or ANI1n pin
(n = 0 to 7), is a mode governed by a trigger specified in the A/D internal trigger selection register 0
(ITRG0).
(d) External trigger mode
External trigger mode, which starts the conversion timing of the analog input set for the ANI0n or ANI1n
pin, is a mode specified using the ADTRG0 or ADTRG1 pin.
CHAPTER 13 A/D CONVERTER
Operation Mode
Select XX010000XXXXXXXXB
Scan XX000000XXXXXXXXB
Select XX011000XXXXXXXXB
Scan XX001000XXXXXXXXB
Select XX010001XXXXXXXXB
Scan XX000001XXXXXXXXB
Select XX010111XXXXXXXXB
Scan XX000111XXXXXXXXB
User's Manual U14492EJ5V0UD
Setting
ADSCM00
XX010000XXXXXXXXB
XX000000XXXXXXXXB
XX011000XXXXXXXXB
XX001000XXXXXXXXB
XX010001XXXXXXXXB
XX000001XXXXXXXXB
XX010111XXXXXXXXB
XX000111XXXXXXXXB
ADSCM10
657