"Serial Relay Output / Opto Input" noob question

jefm

I have a project that need to switch 120vac loads on/off. I'd love to make a PCB for it with relays transistors and all that. But to get started realistically I might just buy a couple of these:
http://cgi.ebay.com/Serial-Relay-Output-Opto-Input-Basic-Stamp-PICAXE_W0QQitemZ140099191163QQcategoryZ4661QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Looks cool and it's ready to go. Question is can I run a few of these on a BS2? I'm pretty sure I know the answer but I haven't done much serial stuff yet and want to be sure before buying!

thanks,
jefm

Mike Green

Can you be more specific in your question? This device (from the documentation) looks like it's specifically designed to be used with a Stamp or equivalent (and they include a sample program). It uses TTL level serial I/O and needs 2 I/O pins (one for SERIN and one for SEROUT use).

You could connect more than one to a Stamp, each to its own set of I/O pins. The Stamp could only talk to one at a time, but these maintain their settings until commanded otherwise. You could only listen to one at a time, but they repeat their status messages once a second, so you'd only have to wait (at a SERIN) for about a second to get a fresh message.

jefm

You kind of answered it already, but I was wondering if more then one of those could be bossed by a Stamp. Which sounds to be the case, I just didn't read enough. My bad, thanks!