RL78/G1P
CHAPTER 9 A/D CONVERTER
R01UH0895EJ0100 Rev.1.00
288
Nov 29, 2019
9.7.5 Setting up test mode
Figure 9-33. Setting up Test Mode
The ADCEN bit of the PER0 register is set (1), and supplying the clock starts.
ADM0 register
FR2 to FR0, and LV0 bits:
These are used to specify the A/D conversion time.
ADMD bit: This is used to specify the select mode.
ADM1 register
ADTMD1 and ADTMD0 bits: These are used to specify the software trigger mode.
ADSCM bit: This is used to specify the one-shot conversion mode.
ADM2 register
ADREFP1, ADREFP0, and ADREFM bits: These are used to select for the reference
voltage source.
ADRCK bit: This is used to set the range for the A/D conversion result comparison
value generated by the interrupt signal to AREA2.
ADTYP bit: This is used to specify 12-bit resolution.
ADUL/ADLL register
These set ADUL to FFH and ADLL to 00H (initial values).
ADS register
ADS4, ADS2 to ADS0 bits: These are used to set to ANI0.
The A/D conversion operations are performed.
The A/D conversion end interrupt (INTAD) is generated.
Note
The conversion results are stored in the ADCR and ADCRH registers.
PER0 register setting
ADM0 register setting
ADM1 register setting
ADM2 register setting
ADUL/ADLL register setting
ADS register setting
ADTES register setting
(The order of the settings is
irrelevant.)
If a test mode is selected (ADTES1 bit of ADTES register = 1) as the analog input
channel: B = 0.5
s
Reference voltage stabilization
wait time count B
Start of A/D conversion
End of A/D conversion
Storage of conversion results in
the ADCR and ADCRH registers
The ADCE bit of the ADM0 register is set (1), and the system enters the A/D conversion
standby status.
ADCE bit setting
ADCS bit setting
After counting up to the reference voltage stabilization wait time count B ends, the ADCS
bit of the ADM0 register is set (1), and A/D conversion starts.
ADTES register
ADTES1, ADTES0 bits: - side reference v side reference voltage
Start of setup
Reference voltage stabilization
wait time count A
The reference voltage stabilization wait time count A is required when the value of the
ADREFP1 and ADREFP0 bits is changed.
If change the ADREFP1 and ADREFP0 = 1, 0:
A = 10
s
If change the ADREFP1 and ADREFP0 = 0, 0 or 0, 1: A = 1
s
Note
Depending on the settings of the ADRCK bit and ADUL/ADLL register, there is a possibility of no interrupt signal
being generated. In this case, the results are not stored in the ADCR and ADCRH registers.
Caution For the procedure for testing the A/D converter, see 20.10 A/D test function.