BS2 on a breadboard

Aidanx1

I have 2 BS2's but only 1 BOE and I want to do some serin/serout experiments. I just need to know what the minimum connections are for using the BS2 from a breadboard. I have a regulated 5V supply.

Thanks


...also, do I need any resistors between the 2 Stamps or can I interface them directly?

Post Edited (Aidanx1) : 3/15/2009 4:19:22 PM GMT

RDL2004

Aside from the IO connections, all the BS2 needs is power (either 5v regulated to vdd or 7.5 to 12v or so to V in) and ground.

However, the BoE does have a connector for a standard serial cable which makes it easy to re-program the Stamp, this is a bit of a pain to do on a regular breadboard. You'd have to hack off the end of a cable to get to the wires, or come up with some type of adapter.

Resistors on the IO pins is always a good idea while experimenting, 220 - 1k ohms or so.

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- Rick

Mike Green

The reason for the resistors is to avoid destroying your Stamp if you make a programming error and set one Stamp I/O pin to output high while the other Stamp's connected I/O pin is set to output low. That makes a short circuit between Vdd and Vss (+5V and ground) and one or both I/O pins burn out. The resistor limits the current to something the Stamp can tolerate.

Aidanx1

Thanks for the answers. Is it neccessary to have both pin 4 AND 23 connected to VSS at all times?...or is pin 4 only used when the stamp is connected to the serial port? I don't intend programming a stamp while it's on the breadboard, I'm just swapping them back and forth from the BOE (although thats probably not great for the pins).

Mike Green

Pins 4 and 23 are connected together on the module. You could manage just connecting one of them.

On an integrated circuit like the Propeller, if you only connect some of the grounds, you can damage the chip under some circumstances.

remmi870

if you are constantly moving a chip in a breadboard i would recommend getting a dip socket with pins and put the chip in the dip socket then just plug the whole assembly in so if you bust a pin, you can just replace the socket.

Aidanx1

Thanks remmi870, I'm doing just that. I have some sockets in the mail from Sparkfun.