31.5.3 ADCON2
Note:
- To correctly calculate an average, the number of samples (set in ADRPT) must be 2CRS.
- CRS =
‘b111
and‘b000
are reserved. - This bit is cleared by hardware when the accumulator operation is complete; depending on oscillator selections, the delay may be many instructions.
- See the “Computation Operation” section for full mode descriptions.
Name: | ADCON2 |
Offset: | 0x1D28 |
Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
PSIS | CRS[2:0] | ACLR | MD[2:0] | ||||||
Access | R/W | R/W | R/W | R/W | R/W/HC | R/W | R/W | R/W | |
Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Bit 7 – PSIS ADC Previous Sample Input Select
Value | Description |
---|---|
1 | ADFLTR is transferred to ADPREV at the start of conversion |
0 | ADRES is transferred to ADPREV at the start of conversion |
Bits 6:4 – CRS[2:0] ADC Accumulated Calculation Right Shift Select
Value | Name | Description |
---|---|---|
1 to 6 | MD = ‘b100 |
Low-pass filter time constant is 2CRS, filter gain is 1:1(2) |
1 to 6 | MD = ‘b011 to ‘b001 |
The accumulated value is right-shifted by CRS (divided by 2CRS)(1,2) |
x | MD = ‘b000 or ‘b111 |
These bits are ignored |
Bit 3 – ACLR A/D Accumulator Clear Command(3)
Value | Description |
---|---|
1 | Registers ADACC and ADCNT and the AOV bit are cleared |
0 | Clearing action is complete (or not started) |
Bits 2:0 – MD[2:0] ADC Operating Mode Selection(4)
Value | Description |
---|---|
111-101 | Reserved |
100 | Low-Pass Filter mode |
011 | Burst Average mode |
010 | Average mode |
001 | Accumulate mode |
000 | Basic (Legacy) mode |