Turning on & off BS2 and TTL stuff

Archiver

Hi all,

What's the best way to turn on a BS2.

I want a preprogrammed stand-alone BS2 to turn on and execute a program when
it sees a TTL logic high from another chip.

What's the best way to do this?

I also want to turn on a + and - 12vdc to power up some opamps.

What's a good way to do this?

I would kinda like to do this without manual switches.

Can you even use mechanical switches to safely turn on TTL or CMOS, like the
BS2 and
opamps??

Thanks,

Mark

Archiver

battery or wall wart operation,

you could use sleep command and wake up to look for pushbutton or switch
actuation, you can turn on relays for +-12 vdc, or if your going to use
a dc to dc converter for the +-12 vdc you could power a transistor to
turn on the converter how fast does it need to turn on.
does the ttl logic stay high or is it pulsed, the stamp could hold it's
own power on using a transistor, and after a time frame or switch
actuation go low and turn off all power. its all in the mind of the
user, sometimes it's what's works I am still going over my old and new
programs and changing things I just keep on learning !

techno masai wrote:
>
> Hi all,
>
> What's the best way to turn on a BS2.
>
> I want a preprogrammed stand-alone BS2 to turn on and execute a program when
> it sees a TTL logic high from another chip.
>
> What's the best way to do this?
>
> I also want to turn on a + and - 12vdc to power up some opamps.
>
> What's a good way to do this?
>
> I would kinda like to do this without manual switches.
>
> Can you even use mechanical switches to safely turn on TTL or CMOS, like the
> BS2 and
> opamps??
>
> Thanks,
>
> Mark

Archiver

Hi Larry,

Thanks for the info, also thanks for your reply last week on the opto
question.

As you suggested I think I'm going to use some transistors. I just kept
thinking there was some cheapo cool way to turn everything on, like maybe a
gang transistor with multiple collectors or something.

Still kinder concerned about turning on an opamp with a mechanical switch.

Mark

---

Original Message

---

From: L .Gaminde <lgaminde@t...>
To: basicstamps@yahoogroups.com <basicstamps@yahoogroups.com>
Date: Sunday, February 11, 2001 6:04 PM
Subject: Re: [noparse][[/noparse]basicstamps] Turning on & off BS2 and TTL stuff


:battery or wall wart operation,
:
:you could use sleep command and wake up to look for pushbutton or switch
:actuation, you can turn on relays for +-12 vdc, or if your going to use
:a dc to dc converter for the +-12 vdc you could power a transistor to
:turn on the converter how fast does it need to turn on.
:does the ttl logic stay high or is it pulsed, the stamp could hold it's
[noparse]:o[/noparse]wn power on using a transistor, and after a time frame or switch
:actuation go low and turn off all power. its all in the mind of the
:user, sometimes it's what's works I am still going over my old and new
[noparse]:p[/noparse]rograms and changing things I just keep on learning !
:
:techno masai wrote:
:>
:> Hi all,
:>
:> What's the best way to turn on a BS2.
:>
:> I want a preprogrammed stand-alone BS2 to turn on and execute a program
when
:> it sees a TTL logic high from another chip.
:>
:> What's the best way to do this?
:>
:> I also want to turn on a + and - 12vdc to power up some opamps.
:>
:> What's a good way to do this?
:>
:> I would kinda like to do this without manual switches.
:>
:> Can you even use mechanical switches to safely turn on TTL or CMOS, like
the
:> BS2 and
:> opamps??
:>
:> Thanks,
:>
:> Mark
:
:
:
:

Archiver

Hi Mark,
Mechanical switches and relays (usually) have point bounce. Can your op amp
circuits and application tolerate this? What is being sensed and what is
being driven? What other options are available to you? Are there rise
time/speed limits? Is this slow speed circuitry? Remember to use by-pass
caps on your op amp power supply leads (at the op amp).
Burt