Parallax BASIC Stamp 2e Programming Manual page 17

Table 1.4: BASIC Stamp 2sx Pin
Descriptions.
1: Introduction to the BASIC Stamps
Pin Name
1 SOUT
2 SIN
3 ATN
4 VSS
5-20 P0-P15
21 VDD
22 RES
23 VSS
24 VIN
See the "BASIC Stamp Programming Connections" section, below, for
more information on the required programming connections between the
PC and the BASIC Stamp.
BASIC Stamp Programming Manual 2.0c • www.parallaxinc.com • Page 15
Description
Serial Out: connects to PC serial port RX pin (DB9 pin 2 / DB25
pin 3) for programming.
Serial In: connects to PC serial port TX pin (DB9 pin 3 / DB25 pin
2) for programming.
Attention: connects to PC serial port DTR pin (DB9 pin 4 / DB25
pin 20) for programming.
System ground: (same as pin 23) connects to PC serial port GND
pin (DB9 pin 5 / DB25 pin 7) for programming.
General-purpose I/O pins: each can source and sink 30 mA.
However, the total of all pins should not exceed 75 mA (source or
sink) if using the internal 5-volt regulator. The total per 8-pin
groups (P0 – P7 or P8 – 15) should not exceed 100 mA (source
or sink) if using an external 5-volt regulator.
5-volt DC input/output: if an unregulated voltage is applied to the
VIN pin, then this pin will output 5 volts. If no voltage is applied to
the VIN pin, then a regulated voltage between 4.5V and 5.5V
should be applied to this pin.
Reset input/output: goes low when power supply is less than
approximately 4.2 volts, causing the BASIC Stamp to reset. Can
be driven low to force a reset. This pin is internally pulled high
and may be left disconnected if not needed. Do not drive high.
System ground: (same as pin 4) connects to power supply's
ground (GND) terminal.
Unregulated power in: accepts 5.5 - 12 VDC (7.5 recommended),
which is then internally regulated to 5 volts. May be left
unconnected if 5 volts is applied to the VDD (+5V) pin.