Datasheet
PIC16F88X
DS80000302H-page 6 2007-2013 Microchip Technology Inc.
3. Module: Analog-To-Digital Converter
(ADC) Module
Selecting the VP6 reference as the analog input
source (CHS<3:0> = 1111) for the ADC
conversion after sampling another analog channel
with input voltages approximately greater than
3.6V can temporarily disturb the HFINTOSC
oscillator.
Work around
Select an ADC channel with input voltages lower
than 3.6V prior to selecting the VP6 reference
voltage input. Any analog channel can be used,
even if that channel is configured as a digital I/O
(configured as an output) that is driving the output
pin low. An alternative is to configure the CV
REF
module to output a voltage less than 3.6V and then
selecting that analog channel CHS<3:0> = 1110
as the analog input source.
EXAMPLE 2: AVOID DISTURBING THE
HFINTOSC OSCILLATOR
Affected Silicon Revisions
PIC16F882
PIC16F883/PIC16F884
PIC16F886/PIC16F887
4. Module: MSSP (SPI Master Mode)
With MSSP in SPI Master mode, FOSC/64 or
Timer2/2 clock rate and CKE = 0, a write collision
may occur if SSPBUF is loaded immediately after
the transfer is complete. A delay may be required
after the MSSP Interrupt Flag bit, SSPIF, is set or
the Buffer Full bit, BF, is set and before writing
SSPBUF. If the delay is insufficiently short, a write
collision may occur as indicated by the WCOL bit
being set.
Work around
Add a software delay of one SCK period after
detecting the completed transfer and prior to
updating the SSPBUF contents. Verify the WCOL
bit is clear after writing SSPBUF. If the WCOL is
set, clear the bit in software and rewrite the
SSPBUF register.
Date Codes that pertain to this issue:
All engineering and production devices.
Affected Silicon Revisions
PIC16F882
PIC16F883/PIC16F884
PIC16F886/PIC16F887
Note: This only occurs when selecting the
VP6 reference ADC channel using the
CHS<3:0> bits in the ADCON0
register and NOT during the start of an
actual ADC conversion using the
GO/DONE
bit in the ADCON0 register.
A0
X
A0
X
A2
X
BANKSEL ADCON0 ;
MOVLW B’XX111001’ ;Select ADC
MOVWF ADCON0 ;Channel CV
REF
MOVLW B’XX111101’ ;Select ADC
MOVWF ADCON0 ;Channel VP6
A0
X
A0
X
A2
X