ISD91200 Series Technical Reference Manual
Release Date: Sep 16, 2019
- 456 -
Revision 2.4
12-bit
Comparator
RSLT >=CMPD
RSLT < CMPD
CMPCOND(ADCMPRx[2])
1
0
ADCMPFx
(STATUS[2:1])
A/D
analog
macro
Channel
Addr.
12
to
1
Analog
MUX
Match
Counter
CMPMATCNT
(CMPx[11:8])
AIN[0]
AIN[11]
……
CHANNEL(STATUS[7:4])
CMPCH(CMPx[6:3])
ADDRx[11:0]
CMPD(CMPx[27:16])
Note:
CMPD=CMPx[27:16]
RSLT=ADDRx[11:0]
Figure 7-25 A/D Conversion Result Monitor Logics Diagram
7.8.3.7
Interrupt Sources
There are three interrupt sources of SARADC interrupt. When an SARADC operation mode finishes its
conversion, the A/D conversion end flag, ADEF, will be set to 1. . The ADCMPF0 and ADCMPF1 are the
compare flags of compare function. When the conversion result meets the settings of ADCMPR0/1, the
corresponding flag will be set to 1. When one of the flags, ADEF, ADCMPF0 and ADCMPF1, is set to 1 and the
corresponding interrupt enable bit, ADCIE of CTL and ADCMPIE of SARADC_CMP0/SARADC_CMP1, is set to
1, the SARADC interrupt will be asserted. Software can clear the flag to revoke the interrupt request.
STATUS.ADCMPF0
CMP0.ADCMPIE
STATUS.ADCMPF1
CMP1.ADCMPIE
SARADC_INT
ADEF
ADCIE
Figure 7-26 A/D Controller Interrupt
7.8.3.8
Peripheral DMA Request
When A/D conversion is finished, the conversion result will be loaded into DATx register and VALID bit will be set
to 1. If the PTEN bit of CTL is set, SARADC controller will generate a request to PDMA. User can use PDMA to
transfer the conversion results to a user-specified memory space without CPU's intervention. The source
address of PDMA operation is fixed at the address of register PDMADAT no matter what channels was selected.
When PDMA is transferring the conversion result, SARADC will continue converting the next selected channel if
the operation mode of SARADC is single scan mode or continuous scan mode. User can monitor current PDMA
transfer data through reading PDMADAT register. If SARADC completes the conversion of a selected channel
and the last conversion result of the same channel has not been transferred by PDMA, overrun OV bit of the
corresponding channel will be set and the last SARADC conversion result will be overwritten by the new
SARADC conversion result. PDMA will transfer the latest data of selected channels to the user-specified
destination address.