Puttering With The Parallax Basic Stamp

microcontrolleruser

Looking at the Pulse Generator on the Professional Development Board 28138.

Is this suitable for testing an oscilloscope?

Here's link to manual.

https://www.parallax.com/sites/default/files/downloads/28138-PDB-Documentation-v2.0.pdf

Publison

Yes, you can connect directly to an oscilloscope, but you can't use it for calibration of said scope.
It is a free running generator and has nothing to do with the BSxx chip installed.

erco

"Puttering with a Stamp" sound like a fine Turkey project. I mean that in a good way today!

microcontrolleruser

Thank you Publison and Erco

Have a question about the RS232 hardware on Professional board.

Is it equivalent to this Futurlec board?

http://www.futurlec.com/Mini_RS232_TTL_5V.shtml

What is DCE?

Publison

From Wikipedia:

Connectors
RS-232 devices may be classified as Data Terminal Equipment (DTE) or Data Circuit-terminating Equipment (DCE); this defines at each device which wires will be sending and receiving each signal. According to the standard, male connectors have DTE pin functions, and female connectors have DCE pin functions. Other devices may have any combination of connector gender and pin definitions. Many terminals were manufactured with female connectors but were sold with a cable with male connectors at each end; the terminal with its cable satisfied the recommendations in the standard.

The standard recommends the D-subminiature 25-pin connector up to revision C, and makes it mandatory as of revision D. Most devices only implement a few of the twenty signals specified in the standard, so connectors and cables with fewer pins are sufficient for most connections, more compact, and less expensive. Personal computer manufacturers replaced the DB-25M connector with the smaller DE-9M connector. This connector, with a different pinout (see Serial port pinouts), is prevalent for personal computers and associated devices.

Presence of a 25-pin D-sub connector does not necessarily indicate an RS-232-C compliant interface. For example, on the original IBM PC, a male D-sub was an RS-232-C DTE port (with a non-standard current loop interface on reserved pins), but the female D-sub connector on the same PC model was used for the parallel "Centronics" printer port. Some personal computers put non-standard voltages or signals on some pins of their serial ports.

Is your Google button broken?

Mike Green

The Futurelec board is similar. The PDB assigns the channels of the MAX232 to Rx,Tx,RTS,CTS while the Futurelec board doesn't assign the channels.
To quote the Wikipedia:
"RS-232 devices may be classified as Data Terminal Equipment (DTE) or Data Circuit-terminating Equipment (DCE); this defines at each device which wires will be sending and receiving each signal. According to the standard, male connectors have DTE pin functions, and female connectors have DCE pin functions."

Publison

The schematic shows they both use the same chip:

https://www.parallax.com/sites/default/files/downloads/28138-PDB-Schematic-RevD.pdf

microcontrolleruser

Thank you Publison and Mike

That cleared it up enough for now.

Next question about motor driver circuit on board. L293D push-pull driver. Not the Servo one.

Will that work for running the motors on this Tamiya robot?

Their powered by two 1.5v batteries. I have not found out that much about them yet.

https://www.tamiyausa.com/shop/educational-construction/remote-control-robot/

microcontrolleruser

"The schematic shows they both use the same chip:"

Yes Publison. It' s a popular chip. Tou find them all over. Like the 7805 regulator and the chip

for the L293D push-pull driver.

microcontrolleruser

This guy went the distance with Tamiya DC motor.

https://www.pololu.com/docs/0J11/all

Looks promising at this point.

I'm going to do Parallax servo lesson.

Any advantage to using servo hardware on Professional over Board of Education?

Genetix

microcontrolleruser,

The Board of Education (BOE) has servo ports that you can plug directly into.

microcontrolleruser

Thank you Genetix

Let me check out the Professional board and find out if the same or better.

Here's pic of a CIE 3310 scope like ours. Ours has same paint scheme.CIE is Cleveland Institute of Electronics.