STAMP 2 Communications And Control Projects.pdf

ALTERNATIVE STAMP 2 7
DB-9 female
PSR
RTS
6
7
8
9
1
2
3
4
5
RX - Sout
TX - Sin
ATM
VSS/GND
1
2
3
4
BASIC
STAMP
2
Figure 1-6
Serial programming port.
sockets to the board. Another approach to using the carrier board concept is to use the
supercarrier board, as illustrated in Fig. 1-9. The supercarrier board contains a number of
more useful aides, such as power regulators, more header pins, serial connections, and
reset switch. Additional IC sockets can be placed on the board for expansion, with jumper
wires added between sockets. This approach is a bit more permanent than using the protoboard.
Many people use the carrier board as their protoboard for simple circuits. Other
hobbyists use the carrier board as a replacement for a printed circuit board.
Alternative STAMP 2
Another approach to obtaining the STAMP 2 is to build your own “alternative” BASIC
STAMP 2. In this configuration you obtain the 28-pin DIP interpreter chip and a few extra
support or “glue” components, and you can save about half the cost of the original STAMP 2
by assembling or “rolling” your own. The alternative STAMP 2 project revolves around the
lower-cost BASIC STAMP 2 interpreter chip, a 16C57 PIC, a 28-pin DIP-style STAMP 2,
rather than the stock BASIC STAMP 2 module. The lower-cost 28-pin PIC BASIC interpreter
chip requires a few external support chips and occupies a bit more real estate, but
the cost is significantly less. The BASIC STAMP 2 costs $49, while rolling you own will
cost about half, or $21. The 28-pin BASIC STAMP 2 interpreter chip requires a few external
support components, a 24LC6B memory chip, a MAX232 serial interface chip, and a
ceramic resonator. The MAX232 requires four 1-F capacitors, a diode, and a resistor and
provides a conventional serial I/O, which is used to program the microprocessor.
The alternative STAMP 2 processor circuit is shown in Fig. 1-10. Both the STAMP 2 and
the alternative STAMP 2 perform equally well for all of the projects in this book. Please note
that the pinout arrangement is a bit different between the original BASIC STAMP 2 and the alternative
STAMP 2 (see Table 1-4). Another alternative is to purchase the original equipment manufacturer
(OEM) module kit from Parallax, which is quite similar to the alternative STAMP 2.