Chip with simple program for Toy

[John G]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113709439.757629.77030@l41g2000cwc.googlegroups.com...

a single AC phase by it's self can't power anything, may it be an AC or
DC circuit, right?

Chris's reply was correct . There is a neon (and resisitor) across the
switch contact.
When the switch is OFF the neon is fed from the hot side thru the load
to neutral.
When the switch is ON the neon is shorted and the load works.

--
John G

Wot's Your Real Problem?

 

[John G]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113713094.309142.67210@g14g2000cwa.googlegroups.com...

I find that strange, because, won't the load's resistance dim or
brighten the switches neon lamp. Or would if the load was a
receptacle.

In the case of a lamp the current used by a neon is so small as to be

insignificant compared to the lamp so will not be dimmed by a change in
lamp power.

If there was no lamp or no load on a receptical then this approach would
not work correctly and it would be better to have the neon on the load
side of the switch withits other end conected to neutral thereby
lighting when the switch is on, not off, regardless of the load.

Having it light when the lamp is off allows you to find the switch in
the dark.
--
John G

Wot's Your Real Problem?

 

[Lord Garth]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113713094.309142.67210@g14g2000cwa.googlegroups.com...

I find that strange, because, won't the load's resistance dim or
brighten the switches neon lamp. Or would if the load was a receptacle.

Neon lamps need a series resistance and the draw extremely little power.

O---------------------------traveler------o--------------------O
| |
(NE2 shorted) |
Hot O---^^^^---neon--- ---neon---^^^^---O---O
incandescent lamp O---O neutral
(NE2 open) |
On
O--------------------o------traveler------o--------------------O

OR

O---------------------------traveler------o--------------------O
|
(NE2 open)
Hot O---^^^^---neon--- ---neon---^^^^---O---O
incandescent lamp O---O neutral
| (NE2 shorted) |
| On
O--------------------o------traveler------o-------------------O





O---------------------------traveler------o--------------------O
| |
Hot O---^^^^---neon--- ---neon---^^^^---O---O
incandescent lamp O---O neutral
|
| Off
O--------------------o------traveler------o--------------------O

OR

O---------------------------traveler------o--------------------O
|
|
Hot O---^^^^---neon--- ---neon---^^^^---O---O
incandescent lamp O---O neutral
| |
Off
O--------------------o------traveler------o-------------------O

 

[Lord Garth]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113758078.070849.76880@l41g2000cwc.googlegroups.com...

I tried connecting a meter, in voltage mode, and it acted weird see:
http://home.nycap.rr.com/joshs/threewaywire.bmp
I also connected the meter to the line, and just one screw and it
lit!!, but very dimly.

Thanks.

Just unscrew the bulb and see if they go out.....

 

[Lord Garth]

"Arie de Muynck" <send.spam.to@spammer.org> wrote in message
news:42624533$0$98488$e4fe514c@news.xs4all.nl...

billb@eskimo.com> ...
Hmmmmmm. Burial or cremation. Only two choices, eh?

Today you can be cremated, then have the carbon from the ashes converted
into a diamond. Nice remainder for your wife (or oldest daughter).
Not cheap though.

http://www.lifegem.com/secondary/lifeline/LifeLine_web_newsletter_e1.pdf

Arie

Gives new meaning to the term 'family jewels', doesn't it!

 

[Bob Monsen]

On Sun, 17 Apr 2005 10:14:38 -0700, js5895 wrote:

I tried connecting a meter, in voltage mode, and it acted weird see:
http://home.nycap.rr.com/joshs/threewaywire.bmp
I also connected the meter to the line, and just one screw and it
lit!!, but very dimly.

Thanks.

Are you saying that the switch itself is illuminated, or that the lamp
plugged into the switch is illuminated? I have a wall switch that is
lighted, in which the light is on when the switch is off.

However is there is a short through the switch, you should replace it.
Sadly, I had trouble interpreting your picture.

For a three way switch, you have this situation:
{view with fixed-point font)

S1
line --[lamp]--o o---------------------oo
\ \
\ \
oo---------------------o o---- neutral
S2

Thus, either of the switches can light the lamp.

If one of the switches has failed such that it is closed on both paths,
or if the wiring is broken in this way, it'll light in either
position. So, for example, if S2 has a path like this:

S1
line --[lamp]--o o---------------------oo
\ \
\ \
oo---------------------oxxxxxxo---- neutral
S2

Then even if the xxxxx path is fairly high resistance, the lamp may
act like you are describing. You can test this by disconnecting
neutral from S2, and line from S1 and testing the resistance between
the two throws of S1. If it is less than 10MEG, you have trouble.

Note that the lamp may be in a different place; thus, I wouldn't trust
that pulling the lamp will disconnect you from line.

----
Regards,
Bob Monsen

 

[Dr. Anton T. Squeegee]

In article <1113753225.807188.160650@f14g2000cwb.googlegroups.com>,
nospam4u_jack@yahoo.com says...

Hi all,

I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.

Sounds to me like you have the wrong type of keypad. Is there a
reason you can't remove the pullup resistors, and simply use the X-Y
lines directly into the chip? That's how most DTMF generators do their
thing.

Keep the peace(es).

--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute.
(Known to some as Bruce Lane, ARS KC7GR,
kyrrin (a/t) bluefeathertech[d=o=t]calm -- www.bluefeathertech.com
"If Salvador Dali had owned a computer, would it have been equipped
with surreal ports?"

 

[Rich Webb]

On 17 Apr 2005 08:53:35 -0700, "Jack// ani" <nospam4u_jack@yahoo.com>
wrote:

Hi all,

I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.

Typically you'd hook up either the row or column pins to a 4-bit port
that is normally outputting a "high" on each pin. Hook the remaining 4
bits to 4 input pins.

Pull one of the output pins down to "low" and read all of the input
bits. If one of the bits is also low, then that row-column corresponds
to the key that is pressed.

A complication: If you are driving, say, columns with the four output
bits, consider that if two keys are pressed in the same row then you'll
have a direct path between an output pin at logic high and one at logic
low. This is generally A Bad Thing. Add diodes or current-limiting
resistors on the output pins. Alternately, you may be able to flip the
"unused" column drivers over to an input state and set only one to be an
output at a time.

And the usual issues with key bounce and multiple simultaneous key
presses.

--
Rich Webb Norfolk, VA

 

[Lord Garth]

"Jack// ani" <nospam4u_jack@yahoo.com> wrote in message
news:1113753215.557562.35960@f14g2000cwb.googlegroups.com...

Hi all,

I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.

Thanks in advance

You need a DTMF chip that can have its keypad inputs grounded to
activate. The MK5089 was such a chip. Most dialers today use
row and column inputs in a 2 of 7 or 2 of 8 arrangement. Your
row column keypad should be fine...can you simply not connect the
pull-up resistors? Any link to the keypad manufacturer?

 

[Jamie]

aman wrote:

Is it possible to use 555 to generate a pulse which triggers after
every 24 hours. Am I looking at an RC time constant which is not at all
feasible ?

i guess if you pass it through a few flip flips, and use an And/Nand

gate combined with the input train and output train to reset the
flops after an event, that way you could set the duration with in a
spec that is suitable for the timer and simply scale it longer via
flip-flops

 

[Lord Garth]

"Bob Monsen" <rcsurname@comast.net> wrote in message
newsan.2005.04.17.17.50.29.922471@comast.net...

On Sun, 17 Apr 2005 10:14:38 -0700, js5895 wrote:

I tried connecting a meter, in voltage mode, and it acted weird see:
http://home.nycap.rr.com/joshs/threewaywire.bmp
I also connected the meter to the line, and just one screw and it
lit!!, but very dimly.

Thanks.

Are you saying that the switch itself is illuminated, or that the lamp
plugged into the switch is illuminated? I have a wall switch that is
lighted, in which the light is on when the switch is off.

However is there is a short through the switch, you should replace it.
Sadly, I had trouble interpreting your picture.

For a three way switch, you have this situation:
{view with fixed-point font)

S1
line --[lamp]--o o---------------------oo
\ \
\ \
oo---------------------o o---- neutral
S2

Thus, either of the switches can light the lamp.

If one of the switches has failed such that it is closed on both paths,
or if the wiring is broken in this way, it'll light in either
position. So, for example, if S2 has a path like this:

S1
line --[lamp]--o o---------------------oo
\ \
\ \
oo---------------------oxxxxxxo---- neutral
S2

Then even if the xxxxx path is fairly high resistance, the lamp may
act like you are describing. You can test this by disconnecting
neutral from S2, and line from S1 and testing the resistance between
the two throws of S1. If it is less than 10MEG, you have trouble.

Note that the lamp may be in a different place; thus, I wouldn't trust
that pulling the lamp will disconnect you from line.

----
Regards,
Bob Monsen

I learned to never switch the neutral line, only the hot (black) wire.
Be careful, you set up a situation where you are the ground link.

Use courier font to view the diagram, it is a fixed width font.
I drew all four possible switch positions. The three O at each end
are the three terminals on the SPDT switches, center is the toggle.
The resistor and series neon are within the switch & connected across
the throws...that's the top and bottom O at the ends. The lines labeled
'traveler' is the interconnect between the switch throws at each end
of the room.

The neons in the switches should go out when the bulb is removed
from the socket. This is because they loose their connection to neutral
through the incandescent bulb.



O--o-----------------traveler------------------o---O
| | (NE2 on) |
Hot O --^^^^---neon-- --neon---^^^^--o O---O incandescent
lamp O---O neutral
(NE2 on) | | | Off
O----------------o---traveler---o------------------O

OR

O--o-----------------traveler------------------o---O
| (NE2 on) | |
Hot O --^^^^---neon-- --neon---^^^^--o O---O incandescent
lamp O---O neutral
| (NE2 on) | | Off
O----------------o---traveler---o------------------O





O--o-----------------traveler------------------o---O
| | (NE2 off) | |
Hot O --^^^^---neon-- --neon---^^^^--o O---O incandescent
lamp O---O neutral
(NE2 off) | | On
O----------------o---traveler---o------------------O

OR

O--o-----------------traveler------------------o---O
| (NE2 off) |
Hot O --^^^^---neon-- --neon---^^^^--o O---O incandescent
lamp O---O neutral
| (NE2 off) | | | On
O----------------o---traveler---o------------------O

 

[Lord Garth]

"Jamie" <jamie_5_not_valid_after_5_Please@charter.net> wrote in message
news:yHy8e.8764$Ow2.2757@fe06.lga...

aman wrote:

Is it possible to use 555 to generate a pulse which triggers after
every 24 hours. Am I looking at an RC time constant which is not at all
feasible ?

i guess if you pass it through a few flip flips, and use an And/Nand
gate combined with the input train and output train to reset the
flops after an event, that way you could set the duration with in a
spec that is suitable for the timer and simply scale it longer via
flip-flops

It might be easier to think backwards, use a presetable DOWN counter and
look for the borrow or terminal count pin to go active. This eliminates the
extra gates.

 

[John Fields]

On 17 Apr 2005 08:53:35 -0700, "Jack// ani" <nospam4u_jack@yahoo.com>
wrote:

Hi all,

I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.

---
Assuming that the pullups are internal to the dialer you can do this:


+V
|
+-----+-----+-----+-----+
| | | | |
[10K] [10K] [10K] [10K] [30K]
| | | | |
+--[10K]--1-----2-----3-----A---------|-\ __
| | | | | | | >------>R1
| | | | | +---|+/
| | | | | |
+--[10K]--4-----5-----6-----B---------|-\ __
| | | | | | | >------>R2
| | | | | +---|+/
| | | | | |
+--[10K]--7-----8-----9-----C---------|-\ __
| | | | | | | >------>R3
| | | | | +---|+/
| | | | | |
+--[10K]--*-----0-----#-----D---------|-\ __
| | | | | | | >------>R4
GND | | | | +---|+/
| | | | |
| | | | [10K]
| | | | |
| | | | GND
| | | |
| | | | +V
| | | | |
| | | | [10K]
| | | | |
| | | +---------|+\ __
| | | | | >------>C4
| | | +---|-/
| | | |
| | +---------------|+\ __
| | | | >------>C3
| | +---|-/
| | |
| +---------------------|+\ __
| | | >------>C2
| +---|-/
| |
+---------------------------|+\ __
| | >------>C1
+---|-/
|
[30K]
_ _
The comparators are LM339s, the Rs and Cs are the row and column
outputs to your dialer, and 1,2,3...D are the crosspoints of your
switches.

--
John Fields
Professional Circuit Designer

 

[John Fields]

On Sun, 17 Apr 2005 16:29:53 -0500, John Fields
<jfields@austininstruments.com> wrote:

On 17 Apr 2005 08:53:35 -0700, "Jack// ani" <nospam4u_jack@yahoo.com
wrote:

Hi all,

I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.

---
Somehow, (my fault) the schematic and text posted slightly garbled.
They should look like this:

+V
|
+-----+-----+-----+-----+
| | | | |
[10K] [10K] [10K] [10K] [30K]
| | | | |
+--[10K]--1-----2-----3-----A---------|-\ __
| | | | | | | >------>R1
| | | | | +---|+/
| | | | | |
+--[10K]--4-----5-----6-----B---------|-\ __
| | | | | | | >------>R2
| | | | | +---|+/
| | | | | |
+--[10K]--7-----8-----9-----C---------|-\ __
| | | | | | | >------>R3
| | | | | +---|+/
| | | | | |
+--[10K]--*-----0-----#-----D---------|-\ __
| | | | | | | >------>R4
GND | | | | +---|+/
| | | | |
| | | | [10K]
| | | | |
| | | | GND
| | | |
| | | | +V
| | | | |
| | | | [10K]
| | | | |
| | | +---------|+\ __
| | | | | >------>C4
| | | +---|-/
| | | |
| | +---------------|+\ __
| | | | >------>C3
| | +---|-/
| | |
| +---------------------|+\ __
| | | >------>C2
| +---|-/
| |
+---------------------------|+\ __
| | >------>C1
+---|-/
|
[30K]
|
GND
_ _
The comparators are LM339s, the Rs and Cs are the row and column
outputs to your dialer, and 1,2,3...D are the crosspoints of your
switches.

--
John Fields
Professional Circuit Designer

 

[Lord Garth]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113776039.129904.6620@f14g2000cwb.googlegroups.com...
There is no bulb, the switch isn't wired up, it's in my hand right now.
I did a test on my desk with a digital clock, by wiring it normally,
hooked up the travelers and tested it with the load connected to
the common, then the line conected to the common and then the
neon stayed lit, when the switch was off, BTW, I'm setting it up
with one neon switch in my dark hall way, and one non-neon, 3-way
switch in the house. I just wanted to know how a switch can light
up inside, with no neutral connection, because it's a switch, and light
up and be off at the same time, FYI, I changed the picture:
http://home.nycap.rr.com/joshs­/threewaywire.bmp

Thanks.

 

[Lord Garth]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113776039.129904.6620@f14g2000cwb.googlegroups.com...
There is no bulb, the switch isn't wired up, it's in my hand right now.
I did a test on my desk with a digital clock, by wiring it normally,
hooked up the travelers and tested it with the load connected to
the common, then the line conected to the common and then the
neon stayed lit, when the switch was off, BTW, I'm setting it up
with one neon switch in my dark hall way, and one non-neon, 3-way
switch in the house. I just wanted to know how a switch can light
up inside, with no neutral connection, because it's a switch, and light
up and be off at the same time, FYI, I changed the picture:
http://home.nycap.rr.com/joshs­/threewaywire.bmp

Thanks.


Yes, it should have a resistive load connected, like an incandescent lamp.
I suspect a fluorescent lamp wouldn't be right either but since the
neon is all that's affected, no big deal. I wonder about folded fluorescent
screw-in replacement lamps.

Were you able to see my diagram using courier font?

Your AOL / RoadRunner link isn't working here. :-|

 

[Lord Garth]

"Lessie" <lessie@btinternet.com> wrote in message
news:7c3b95d1.0504171447.315c1d47@posting.google.com...

Pickit1 has 8 red leds which are controlled by
RA1/2/4/5. I was just wondering if there is any
special reason why the leds are arranged in the
way they are?
tnx

The board layout was probably the dictating factor. The OS author just made
minor changes
to reflect the physical orientation.

 

[Rein Wiehler]

Jack// ani wrote:

Like a map for Road to El dorado!

I can show you one for Eldoret

 

[John Popelish]

stu@aaronj.com wrote:

I will soon wire up a 36 Volt 80 Amp permanent magnet DC motor to be
run at 48 VDC. It will be used in a homebuilt trike.

I am looking for a flyback diode that will take the full current during
slowdown when the power is turned off by a contactor (no PWM).

I would appreciate knowing whether to use a single diode, series
diodes, a Schottky, a series resistor, etc.

What is the most cost effective solution?


Boyntonstu

If you include the time cost of connecting big wires to the diode and

heat sinking it, you may be ahead by selecting something easy to
mount. A DO-5 stud package might be good, but I think a Half-Pak is
better. A 120 amp 100 volt Schottky costs about $17 plus shipping
from Digikey: http://www.irf.com/product-info/datasheets/data/123nq.pdf

 

[Lord Garth]

"js5895" <JoshTmp@nycap.rr.com> wrote in message
news:1113782768.468929.190320@z14g2000cwz.googlegroups.com...

Oh, sorry, here:
http://home.nycap.rr.com/joshs/threewaywire.bmp

Hmm, You know, you're going to make me go buy a switch just to cut it
open! The setup should have been equivalent with the line & neutral
either way though it needs an incandescent load. I hope you weren't
reading voltage since you have your meter is in series. Reading current
can lead to some bright flashes that you won't want to see when the
source is the mains, usually current is read with a clamp on current probe
for your own safety and the life of your meter.

Your picture makes it hard to tell what is the pole and which are the
throws. I'm going with top being the pole and the bottom two being
the throws. If so, then I don't know how the neon lit at all. My though
was that the neon was across the throws.