Overview
In order to make use of a BASIC Stamp, you must first connect it to a personal computer for programing. Once the Stamp has been programmed, you don't need the connection anymore. The program stays in the Stamp's memory, and will run from the beginning every time you turn on the Stamp.The programming connection between a Stamp and personal computer is conceptually simple. But this simple task is complicated by a number of variables. In the first place, there are many different kinds of connections on computers, and some are better suited to Stamp programming than others. Secondly, different models of BASIC Stamp have different connections.
So, we have to play a game, using various plugs, cables, and adapters - to get from one side to the other.
If your personal computer and BASIC Stamp do not exactly match these
"canned" configurations, you must figure out
what type of connection your PC offers,
what type of connection your BASIC Stamp requires,
and then see
Some Combinations.
The connector on the right is the socket on a BS1 Project Board.
Requirements:
You string the parts together like this:
The bottom picture is the USB socket on the back of a Toshiba notebook PC.
This is the connector that your PC should have!
Note: Some computers use different connectors for USB. You might need an adapter or a different cable.
Requirements:
You string the parts together like this:
Most Likely Situations
This section describes connectivity solutions for some of the most common configurations.
Serial Port to Prop-1 controller
This section assumes that your personal computer has a serial port
and that you are using the Prop-1 controller.
The connector on the left happens to be the end of an extender cable,
but it is the same thing that you should see exposed on your PC.
PC (serial port) == Serial Extension Cable == Serial Adapter == PROP-1
USB Port to Prop-1 controller
This section assumes that your personal computer has a USB port
and that you are using the Prop-1 controller.
The top picture is the plug on the end of a USB peripheral cable.
PC (USB port) == USB-To-Serial Converter == Serial Adapter == PROP-1
Some Combinations
The exact model of BASIC Stamp will dictate the type of
programming port
that it has.
The
I/O ports on your computer
dictates what it can talk to.
There are various
connectivity products
that can be strung together in fascinating ways to get from one end to the other.
| Stamp programming port | Available PC ports | ||
|---|---|---|---|
| Parallel Port | Serial Port | USB Port | |
| Classic BS-1 Interface | BS1 Parallel Programming Cable | Serial Extension Cable Serial Adapter |
USB-To-Serial Converter Serial Adapter |
| Common BS-2 Interface | Serial Extension Cable carrier board |
USB-To-Serial Converter carrier board |
|
| Serial Port | Serial Extension Cable | USB-To-Serial Converter | |
| USB Port | USB Cable | ||
Make sure that you read your documentation carefully, so that you understand
exactly what kind of programming port your stamp has!
This programming connection was designed around a special cable attached to a
PC parallel port.
Not all the bits from the printer port were used; in fact only three wires were used.
It is still theoretically possible to make or buy a
BS1 Parallel Programming Cable
to connect your BS-1 to a printer port and program it that way.
But in practice, you are better off using a
Serial Adapter
on your BS-1, so that is can be programmed through a common
PC Serial Port.
The interface between the serial port and the Stamp is simple - it uses
four wires and two capacitors.
But I haven't seen Parallax selling a cable that goes from the computer's serial port
to the Stamp.
Instead, the trend is to plug the BS-2 into a carrier board that contains a serial connector,
which is then wired using a
Serial Extension Cable.
Examples:
In all of these examples, the Stamp circuitry has its own native interface,
but the Stamp is embedded into a project board which presents a different (easier) interface
that is compatible with your
PC Serial Port.
Examples:
In all of these examples, the Stamp circuitry has its own native interface,
but the Stamp is embedded into a project board which presents a different (easier) interface
that is compatible with your
PC USB Port.
The bottom picture is the parallel printer port socket on the back of a Toshiba notebook PC.
The connector on the right is the socket on a BS1 Project Board.
The bottom picture is the USB socket on the back of a Toshiba notebook PC.
Note: Some computers use different connectors for USB. You might need an adapter or a different cable.
This is the cable that you would use:
This connection type was originally used in the days of DOS.
It is still theoretically usable, with the old IDE, running in a DOS shell window.
But this should be considered a last resort.
Parallax encourages customers to use a
Serial Adapter,
which makes the Stamp programmable through a
PC serial port
or
PC USB port
(by adding a USB-to-serial converter).
There is nothing magic about this particular cable.
It just takes the serial port connector, usually hidden on the back of your PC,
and makes it available on your desk, where the Stamp is being worked on.
Similar cables are available almost everywhere that sells computer supplies.
If you choose to shop for an alternative look for:
There are a few
Stamp products with a USB Port,
but the best approach is probably to give back to your PC the
serial port that they left off at the factory.
A "USB-To-Serial Converter" (or "Serial-To-USB Converter", because it does both)
plugs into a
PC USB Port
and gives you a
PC Serial Port.
This is the version sold by Parallax:
There are many USB-To-Serial Converters on the market,
with different chips inside, using different drivers,
sold under different brands, for different prices.
Urban legend has it that some are better than others.
[JohnB of Parallax says that they have had problems with Belkin models,
because the DTR pin is not implemented.]
Parallax claims to have tested many versions before
deciding to sell this one based on the FTDI chip.
If you want something that is guaranteed to work in programming a Stamp, get this one.
NOTES:
You simply put this converter on your BS-1, and it can be programmed through a
PC Serial Port.
If you don't have a serial port, you can make one with a
USB-To-Serial Converter.
WARNING: The part of the Serial Adapter that plugs into the BASIC Stamp does not
have a polarization "key" to prevent it from being plugged in wrong.
Look at the ">>" markings on the adapter, and match them to the markings on the Stamp.
Programming Port On The Stamp
A BASIC Stamp controller is nothing until you connect it to a computer and program it.
After that, the Stamp can operate independently.
This section lists the numerous ways that various different types of Stamps hook up.
Classic BS-1 Interface
The earliest versions of the BASIC Stamp controllers were programmed using
the computer's parallel port.
As the Stamp family matured, other types of connections appeared.
But older BASIC Stamp models, and modern implementations of the classic BS-1
still use the classic BS-1 interface.
Common BS-2 Interface
All Stamps in the BS-2 family use a programming connection attached to a computer's
serial port.
Serial Port
Stamps themselves do not have serial programming ports.
They will use either
Classic BS-1 Interface
or
Common BS-2 Interface.
But some special development and educational platforms offer alternative programming ports.
USB Port
Stamps themselves do not have USB programming ports.
They will use either
Classic BS-1 Interface
or
Common BS-2 Interface.
But some special development and educational platforms offer alternative programming ports.
I/O Ports On Your Computer
Parallel Port
A PC's parallel port is usually exposed as a 25-pin "D" connector.
The top picture is the plug on the end of a parallel printer cable.
Serial Port
A PC's serial port is usually exposed as a 9-pin "D" connector.
The connector on the left is the end of an extender cable,
but is the same thing that you should see exposed on your PC.
USB Port
A PC's parallel port is usually exposed as a flat, rectangular connector.
Looking inside, you can see four electrical contacts.
The top picture is the plug on the end of a USB peripheral cable.
Parallax Connectivity Products
This section lists some Parallax products that may be useful in the connectivity chain
between your coumputer and your Stamp-based controller.
Please note that some of these products may be available
elsewhere at different prices, with different features.
But to keep things simple, I will use the Parallax products as examples.
BS1 Parallel Programming Cable
The earliest versions of the BASIC Stamp controllers used the
Classic BS-1 Interface,
which connected to a
PC Parallel Port.
Not all the bits were used; in fact only three wires were necessary.
Parallel Cable
Stock#: 800-00001
Weight: 0.3 lb.
Cost: Special Order item.
Serial Extension Cable
This cable is a simple
PC Serial Port
extension cable.
It has a female 9-pin D connector on one side and a male connector on the other.
Serial Cable (for BS2 programming)
Stock#: 800-00003
Price: $10.00 [6/2005]
Weight: 0.3 lb.
Here's a really cheap one, made from a 9-conductor piece of ribbon cable with connectors attached to each end.
USB-To-Serial Converter
When Parallax changed over from
Classic BS-1 Interface
to the
Common BS-2 Interface,
they probably did so because
PC Serial Ports
were becoming more common and
PC Parallel Ports
were becoming more rare.
Now, more and more computers (especially laptops) are even leaving off the serial port,
in favor of
USB Ports.
FTDI US232B USB to Serial Adapter (includes #27000-0)
Stock#: 800-00030
Price: $34.00 [6/2005]
Weight: 0.15 lb.
I bought this one, a different brand, at
Fry's
for $15 [June 2005] and it worked fine.
Serial Adapter
With
PC Parallel Ports
getting harder and harder to find, Parallax needed a way to continue supporting the
Classic BS-1 Interface.
The answer is this small converter:
BASIC Stamp 1 Serial Adapter
Stock#: 27111
Price: $4.95
Weight: 1 lb.