STAMP 2 Communications And Control Projects.pdf

APPROACHES TO CONSTRUCTION 5
commands that interface with the parts listed above. It is a great solution for those needing
more power than a BS2-IC offers.
The BASIC STAMP 2E (BS2E-IC), using the Ubicom SX microcontroller, runs at the
same speed as BASIC STAMP 2, but has the RAM and EEPROM size benefits of the
BS2SX, without the speed and power consumption. It is ideal for those who use the BS2
and would like more variable or program space.
Most of the projects in this book will center around the BS2-IC, which was the first and
most popular version of the STAMP 2. A schematic diagram of the original BASIC
STAMP 2 (BS2-IC) is shown in Fig. 1-5. The original BASIC STAMP 2 contains the SOIC
version of the PIC16C57 chip at U1, the external memory chip at U2, a reset chip at U3,
and a voltage regulator at U4. Finally, Q1 through Q3 are used as serial port input conditioners.
Figure 1-6 illustrates the serial port programming pinouts on the original BS2. The
first four pins on the left of the BS2 carrier are the serial port connections. Pin 1 on the
BS2 is the S out
or RX pin, which connects to pin 2 of an RS-232 DB-9 serial female connector.
Pin 2 on the BS2 is the S in
or TX pin, connecting to pin 3 of the DB-9. Pin 3 on the
BS2 is the ATN pin which connects to pin 4 of the DB-9, and finally pin 4 of the BS2 is
the ground connection on pin 5 of the DB-9 connector. Note, that pins 6 and 7, or DSR and
RTS pins, are tied together on the serial port connector.
Table 1-2 illustrates a memory map of the BS2-IC. The memory map shows where program
information is stored; it also clarifies how to access inputs and outputs of the STAMP
2. Table 1-3 depicts the STAMP 2 pinouts and this chart describes each of the pins and
their respective functions.
Approaches to Construction
When constructing circuits using the BASIC STAMP 2, there are a number of different
approaches you can take. One often-used approach to building and testing new microprocessor
and electronic circuits is using the protoboard. The protoboard allows the beginner
as well as the seasoned engineer or technician to test new circuits before he or she commits
them to a special circuit board. The Parallax NX1000 protoboard is shown in Fig. 1-7.
This advanced protoboard is a dream to use. It contains extra components to make new circuit
testing go smoothly. The NX1000 protoboard sports serial ports, voltage regulator,
LEDs, switches, extra input and output connections, and the like. Using this type of protoboard
you can easily change wires and add new components quite simply on the fly.
Another approach is to use a simple, no-frills protoboard. The simple protoboard consists
of the inner white portion of the NX1000. Using this approach, you will need to supply all
the extras yourself. This approach is somewhat cheaper but takes up more real estate on
your bench top.
Many hobbyists choose the STAMP 2 and a simple carrier board, depicted in Fig. 1-8,
which allows building a circuit on the carrier board with the BS2 onboard. The simple BS2
carrier board incorporates a STAMP 2 socket, a 9-V battery terminal, and a serial connector,
as well as single row of header jacks, to facilitate connecting between the STAMP 2
and other points on the board. Using this approach, you would solder other components to
the board and run jumper wires between components. Many hobbyists add additional IC