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Amphibionics 06 3/24/03 9:02 AM Page 232
Amphibionics
PIC 16C71
The Microchip PIC 16C71 is very similar to the PIC 16F84 that has
been used throughout the book. The pinouts are identical. The dif-
ference is that the pins on PortA of the 16C71 can be configured to
take advantage of four on-chip analog-to-digital converters.
Another difference is that the chip is erased by exposure to ultra-
violet light. A small window on the top of the device allows light to
get at the chip. After the chip has been programmed, the window
should be covered with a sticker so that it does not get erased if it
is exposed to sunlight or fluorescent lighting. The 8-bit resolution
of the 4-channel high-speed 8-bit A/D is ideally suited for appli-
cations requiring a low-cost analog interface. Use of the A/D con-
verters will be discussed when the software routines are covered.
Although the 16C71 device was used in the book, Microchip now
manufactures an 18-pin, flash erasable device with analog-to-dig-
ital converters, identified as the PIC 16F818. Figure 6.49 shows
the PIC 16C71 with its ultraviolet erase window. The parts needed
to build the transmitter are listed in Table 6.4.

FIGURE 6.49
Microchip PIC 16C71.

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