PIC16C641 Datasheet, PDF (1/4 Pages) Microchip Technology – Silicon Errata Sheet

PIC16C641
PIC16C641 Rev. A Silicon Errata Sheet
The PIC16C641 (Rev. A) parts you have received con-
form functionally to the Device Data Sheet (DS30559A),
except for the anomalies described below.
All the problems listed here will be addressed in future
revisions of the PIC16C641 silicon.
1. Module: Timer0
The TMR0 register may increment when the WDT
postscaler is switched to the Timer0 prescaler. If
TMR0 = FFh, this will cause TMR0 to overflow (set-
ting T0IF).
Work Around
Follow the following sequence:
a) Read the 8-bit TMR0 register into the W register
b) Clear the TMR0 register
c) Assign WDT postscaler to Timer0
d) Write W register to TMR0
2. Programming: Code Protect Bits
The user could see the following error messages
when using PROMATE to program the devices. The
messages are for the configuration bits only.
Work Around
a) After a program or verify, there could be an indica-
tion that there was a config. bit error. If the error
box shows all configuration bits as correct but does
not show the code protect bits (CP), then the
device was properly programmed but code protect
will not operate.
b) When reading in a part, you may get an error that
indicates that the code protect bits are invalid and
the device is unusable. Again, the device was
properly programmed but code protect will not
operate.
In both cases, the part was programmed correctly
but code protect will not operate.
Note: As with any windowed EPROM device, please cover the window at all times, except when erasing.
© 1998 Microchip Technology Inc.
DS30559A/C641/E2A1-page 1