PIC18F2331_10 Datasheet, PDF (254/392 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High-Performance PWM and A/D

PIC18F2331/2431/4331/4431
21.9.1 A/D RESULT REGISTER
The ADRESH:ADRESL register pair is the location
where the 10-bit A/D result is loaded at the completion
of the A/D conversion. This register pair is 16 bits wide.
The A/D module gives the flexibility to left or right justify
the 10-bit result in the 16-bit result register. The A/D
Format Select bit (ADFM) controls this justification.
Figure 21-5 shows the operation of the A/D result
justification. The extra bits are loaded with ‘0’s. When
an A/D result will not overwrite these locations (A/D
disable), these registers may be used as two general
purpose 8-bit registers.
FIGURE 21-5:
A/D RESULT JUSTIFICATION
ADFM = 1
10-Bit Result
ADFM = 0
7
2107
0
0000 00
ADRESH
ADRESL
10-Bit Result
Right Justified
7
0765
0
0000 00
ADRESH
ADRESL
10-Bit Result
Left Justified
EQUATION 21-3: CONVERSION TIME FOR MULTI-CHANNEL MODES
Sequential Mode:
T = (TACQ)_A + (TCON)_A + [(TACQ)_B – 12 TAD] + (TCON)_B + [(TACQ)_C – 12 TAD] + (TCON)_C + [(TACQ)_D – 12 TAD] + (TCON)_D
Simultaneous Mode:
T = TACQ + (TCON)_A + (TCON)_B + TACQ + (TCON)_C + (TCON)_D
DS39616D-page 254
 2010 Microchip Technology Inc.