On 2008-05-07, CBFalconer <cbfalconer@yahoo.com> wrote:
> Reminds me of the original IBM monochrome display for the PC.
> Set a wrong time or rep rate in the bios and the display cooks
> the horizontal (I think) drive transistor.
Been there, done that. Some of the registers in the original
mono display controller card were write-only. Any accesses to
those register's addresses were handled as writes. If you
tried to read them, you ended up writing unkown values. I
attempted to read the wrong set of I/O addresses using debug,
and I let the smoke out of one of the high-voltage sections of
the display.
--
Grant Edwards grante Yow! Gee, I feel kind of
at LIGHT in the head now,
visi.com knowing I can't make my
satellite dish PAYMENTS!
Reply by CBFalconer●May 7, 20082008-05-07
s0lstice wrote:
> Hans-Bernhard Br�ker <HBBroe...@t-online.de> wrote:
>> s0lstice wrote:
>>
>>> Put half an amp through your LEDs without current limiting
>>> resistors and you may create one ;->
>>
>> Actually, I would expect that to produce a sound instead. As in:
>> PING and they're gone.
>
> It might not be the LED that goes.
Reminds me of the original IBM monochrome display for the PC. Set
a wrong time or rep rate in the bios and the display cooks the
horizontal (I think) drive transistor.
--
[mail]: Chuck F (cbfalconer at maineline dot net)
[page]: <http://cbfalconer.home.att.net>
Try the download section.
** Posted from http://www.teranews.com **
Reply by s0lstice●May 7, 20082008-05-07
On 6 May, 21:39, Hans-Bernhard Br=F6ker <HBBroe...@t-online.de> wrote:
> s0lstice wrote:
> > Put half an amp through your LEDs without current limiting resistors
> > and you may create one ;->
>
> Actually, I would expect that to produce a sound instead. As in: PING
> and they're gone.
It might not be the LED that goes.
Reply by ●May 6, 20082008-05-06
s0lstice wrote:
> Put half an amp through your LEDs without current limiting resistors
> and you may create one ;->
Actually, I would expect that to produce a sound instead. As in: PING
and they're gone.
Reply by s0lstice●May 6, 20082008-05-06
On 4 May, 21:38, Tom=E1s =D3 h=C9ilidhe <t...@lavabit.com> wrote:
> On May 4, 8:27 pm, Dombo <do...@disposable.invalid> wrote:
>
> > You could save two I/O pins if connect the input buttons to a voltage
> > divider network on one side and the other side of the buttons to an
> > analog input of your uC.
>
> Thanks for pointing that out, it hadn't crossed my mind. I'm looking
> into it.
>
> Now I just need to find something frivolous to do with two extra
> pins :-D Any ideas? I've already got seven segment displays and a
> piezo speaker. What else can I put on it? It's a shame they don't have
> chips that can give out a smell :P
Put half an amp through your LEDs without current limiting resistors
and you may create one ;->
Reply by ●May 4, 20082008-05-04
On May 4, 9:38=A0pm, Tom=E1s =D3 h=C9ilidhe <t...@lavabit.com> wrote:
> On May 4, 8:27=A0pm, Dombo <do...@disposable.invalid> wrote:
>
> > You could save two I/O pins if connect the input buttons to a voltage
> > divider network on one side and the other side of the buttons to an
> > analog input of your uC.
>
> Thanks for pointing that out, it hadn't crossed my mind. I'm looking
> into it.
Actually do you think it would be worth the hassle having to deal with
the user pressing more than one button simultaneously?
Reply by ●May 4, 20082008-05-04
On May 4, 8:27=A0pm, Dombo <do...@disposable.invalid> wrote:
> You could save two I/O pins if connect the input buttons to a voltage
> divider network on one side and the other side of the buttons to an
> analog input of your uC.
Thanks for pointing that out, it hadn't crossed my mind. I'm looking
into it.
Now I just need to find something frivolous to do with two extra
pins :-D Any ideas? I've already got seven segment displays and a
piezo speaker. What else can I put on it? It's a shame they don't have
chips that can give out a smell :P
Reply by Rocky●May 4, 20082008-05-04
On May 4, 8:53=A0pm, Tom=E1s =D3 h=C9ilidhe <t...@lavabit.com> wrote:
> > Just out of curiosity - what are the other pins on the PIC being used
> > for?
>
> I've 12 pins available altogether:
>
> * 7 are going to LED's.
> * 1 is clocking a counter.
> * 3 are taking input from buttons.
> * 1 is turning a piezo speaker on and off.
>
> Here's my current schematic:
>
> http://freepdfhosting.com/uploads/c01e0f0837.pdf
>
> It has NPN transistors where it should have PNP because I've just
> recently changed the chips I'm using. I plan on replacing the bi-polar
> transistors with MOSFET's, just as soon as I figure out which ones are
> suitable. I need one that can pass 500 mA, and another that can pass 2
> A.
Thanks - It explains the pre-occupation with wanting 1 pin to drive
the counter/shiftregister. I think there better ways of handling the
problem, but I'm off to bed now.
Rocky
>> Just out of curiosity - what are the other pins on the PIC being used
>> for?
>
> I've 12 pins available altogether:
>
> * 7 are going to LED's.
> * 1 is clocking a counter.
> * 3 are taking input from buttons.
> * 1 is turning a piezo speaker on and off.
>
> Here's my current schematic:
>
> http://freepdfhosting.com/uploads/c01e0f0837.pdf
>
> It has NPN transistors where it should have PNP because I've just
> recently changed the chips I'm using. I plan on replacing the bi-polar
> transistors with MOSFET's, just as soon as I figure out which ones are
> suitable. I need one that can pass 500 mA, and another that can pass 2
> A.
You could save two I/O pins if connect the input buttons to a voltage
divider network on one side and the other side of the buttons to an
analog input of your uC.
Reply by ●May 4, 20082008-05-04
> Just out of curiosity - what are the other pins on the PIC being used
> for?
I've 12 pins available altogether:
* 7 are going to LED's.
* 1 is clocking a counter.
* 3 are taking input from buttons.
* 1 is turning a piezo speaker on and off.
Here's my current schematic:
http://freepdfhosting.com/uploads/c01e0f0837.pdf
It has NPN transistors where it should have PNP because I've just
recently changed the chips I'm using. I plan on replacing the bi-polar
transistors with MOSFET's, just as soon as I figure out which ones are
suitable. I need one that can pass 500 mA, and another that can pass 2
A.