PIC relays control

[Pic_User]

Hi Dom,

As I see it:
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1883&stc=1&d=118558263 1" />
You would need a 5V relay to drive it directly.
The PIC 25mA limit would drive 200 or more coil Ohms.
Not:
Mono-stable Relay, normal relay that stays energized while a voltage is on the coil.
But:
Magnetically Latching, or Mechanical Latching Relays
Bi-stable Relay, “Latching “, usually means a pulse turns it on, a second pulse turns it off.
Single Coil Latching (1 coil latching), usually means the second pulse goes to same connection.
A single PIC I/O could give a pulse to turn it on, then later a second pulse would turn it off.

Dual Coil Latching (2 coil latching), usually means a pulse on coil A turns it on, a pulse on coil B turns it off.
This would require 2 I/O pins for control.

Here is a hook-up if you want to use a 12V relay.
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=1884&stc=1&d=118558290 6" />

You could also use a SCR that would latch with an impulse from a PIC I/O pin. It would be more difficult to un-latch.
-Adam-