Auto reset of BS2
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Posts: 46,084
Hi group,
Onto a project, I use a circuit with BS2 to control a video camera
outside and on this
project, I can plug an LCD serial with a keypad via a 14 pins connector
for setup. But, I also use this same 14 pins connector, for practical
reasons, to plug the selial
cable from my computer to download program into the BS2. Sometime, it
seem that the
BS2 reset by himself when I plug my LCD connector to the 14 pins
connector. I doubt the reason is may be static current from the long
flat cable of my LCD box to
the 14 pins connector which connect also on the programming port of the
BS2 ( pins
# 1, #2, #3 and #4) may reset the BS2 even if thoses wires from the flat
cable are'nt
connected in the LCD box but still act as an antenna.
The question is; can I disconnect the pin #3 (ATN) and still be abble to
redownload
program into the BS2, or just add small capacitors to it to "capture"
static, and
should I do the same with pin #2 (Sin)? If yes , which capacitor value
should be the
best? Is the BS2 resettable by the pin #2
Thank you very much!
Rene
Onto a project, I use a circuit with BS2 to control a video camera
outside and on this
project, I can plug an LCD serial with a keypad via a 14 pins connector
for setup. But, I also use this same 14 pins connector, for practical
reasons, to plug the selial
cable from my computer to download program into the BS2. Sometime, it
seem that the
BS2 reset by himself when I plug my LCD connector to the 14 pins
connector. I doubt the reason is may be static current from the long
flat cable of my LCD box to
the 14 pins connector which connect also on the programming port of the
BS2 ( pins
# 1, #2, #3 and #4) may reset the BS2 even if thoses wires from the flat
cable are'nt
connected in the LCD box but still act as an antenna.
The question is; can I disconnect the pin #3 (ATN) and still be abble to
redownload
program into the BS2, or just add small capacitors to it to "capture"
static, and
should I do the same with pin #2 (Sin)? If yes , which capacitor value
should be the
best? Is the BS2 resettable by the pin #2
Thank you very much!
Rene
Comments
The IDE uses ATN to reset the BS2 before programming.
You could put a switch on it, and only close the
switch when you want to program.
You can put two 0.1 uF capacitors in the ATN line
(one serial, one to ground) to de-couple DC values
-- but it's the transient that gets through, and
that resets the BS2.
The BS2 is not resettable by SERIN, as far as I know.
It IS resettable by pulling the supply voltage down,
which may happen when you plug in your LCD.
--- In basicstamps@yahoogroups.com, Rene Genest <rene.genest@q...>
wrote:
> Hi group,
>
> Onto a project, I use a circuit with BS2 to control a video camera
> outside and on this
> project, I can plug an LCD serial with a keypad via a 14 pins
connector
> for setup. But, I also use this same 14 pins connector, for
practical
> reasons, to plug the selial
> cable from my computer to download program into the BS2. Sometime,
it
> seem that the
> BS2 reset by himself when I plug my LCD connector to the 14 pins
> connector. I doubt the reason is may be static current from the long
> flat cable of my LCD box to
> the 14 pins connector which connect also on the programming port of
the
> BS2 ( pins
> # 1, #2, #3 and #4) may reset the BS2 even if thoses wires from the
flat
> cable are'nt
> connected in the LCD box but still act as an antenna.
>
> The question is; can I disconnect the pin #3 (ATN) and still be
abble to
> redownload
> program into the BS2, or just add small capacitors to it
to "capture"
> static, and
> should I do the same with pin #2 (Sin)? If yes , which capacitor
value
> should be the
> best? Is the BS2 resettable by the pin #2
>
> Thank you very much!
>
> Rene
You should put the caps in the ATN line so the that BASIC Stamp can be
reset external (from the compiler) and yet still run with programs (like
HyperTerminal) that keep the DTR line (that connects to ATN) in a fixed
state. You can find schematics of our programming boards on our web
site that shows how the caps are installed ahead of the ATN pin (one in
series, the other to ground).
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: Rene Genest [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=6CKANn941CHQ1_JAET9O6XESmZk29BRtMI_gHlVm4oVsRw7IxX7xzrhA0JjgxFNSMM17sFSj95ImzeJYGFW3Sc10]rene.genest@q...[/url
Sent: Wednesday, March 24, 2004 7:45 PM
To: stamp
Subject: [noparse][[/noparse]basicstamps] Auto reset of BS2
Hi group,
Onto a project, I use a circuit with BS2 to control a video camera
outside and on this project, I can plug an LCD serial with a keypad via
a 14 pins connector for setup. But, I also use this same 14 pins
connector, for practical reasons, to plug the selial cable from my
computer to download program into the BS2. Sometime, it seem that the
BS2 reset by himself when I plug my LCD connector to the 14 pins
connector. I doubt the reason is may be static current from the long
flat cable of my LCD box to the 14 pins connector which connect also on
the programming port of the BS2 ( pins # 1, #2, #3 and #4) may reset the
BS2 even if thoses wires from the flat cable are'nt connected in the LCD
box but still act as an antenna.
The question is; can I disconnect the pin #3 (ATN) and still be abble to
redownload program into the BS2, or just add small capacitors to it to
"capture" static, and should I do the same with pin #2 (Sin)? If yes ,
which capacitor value should be the best? Is the BS2 resettable by the
pin #2
Thank you very much!
Rene