Chip with simple program for Toy

John Popelish wrote:

I can see no errors in your layout. I would be looking for sneak paths
under C2, or a solder bridge where a hot line runs between two pins of
the connector row. Are the chip, bridge and diode oriented correctly?
Click to expand...
Thank you for your reply.

I've now checked, thrice, the places you suggested without being able to
find any solder bridge or what so ever. Also, the IC, bridge and diode are
using correct orientation.

The board was residing in a box for a fresh project I build straight to
the number from the magazine. It doesn't do as supposed, to I used my DMM
to measure around on the board. The magazine tells me that the Vref on the
723 should be around 7 volts. When the board is in the board, Vref is
around 28 volts, and that's the reason I plugged it out and tested it
outside the box using only the mains-wires.

The weird thing, is that when the board is outside the box, Vref is 7
volts as it should. I take this that it means the board is okay, no solder
bridges, but the other components (connected to the board via the
connector pins) could possibly be erronious, so I guess I'll have to
connect one cable at a time to find the error source.


--
Sincerely, | http://bos.hack.org/cv/
Rikard Bosnjakovic | Code chef - will cook for food
------------------------------------------------------------------------
 
"John Popelish" <jpopelish@rica.net> wrote in message
news:huedndI1QrqHOQnenZ2dnUVZ_tKdnZ2d@adelphia.com...
Rikard Bosnjakovic wrote:
I got a pcb-layout from a magazine, but since I've only got veroboards
at home I had to relayout it to fit a veroboard.

I've now completed the circuit and construction, but obviously there's
an error somewhere that I cannot find. I've double double checked my
layout but still cannot find it.

The original, flawless, pcb-layout from the magazine can be found here:

http://bos.hack.org/tmp/vero_pcb/pcb.jpg

And my veroboard-version for the same layout can be found here:

http://bos.hack.org/tmp/vero_pcb/Veroboard.pdf


I would be very grateful if there is anyone that's got some spare time
(around 5 minutes) to "proofread" my layout and see if there are any
errors.

Thank you.


I can see no errors in your layout. I would be looking for sneak
paths under C2, or a solder bridge where a hot line runs between two
pins of the connector row. Are the chip, bridge and diode oriented
correctly?
Click to expand...
And have you cut the tracks under IC1?

Cheers.

Ken
 
Could you give me the reference of your paper, please?

Eric
 
"Jasen Betts" <jasen@free.net.nospam.nz> wrote in message
news:4c98.43955d07.70e83@clunker.homenet...
On 2005-12-06, Dan Lenski <dlenski@gmail.com> wrote:
I just built this microcontroller programmer,
http://www.myke.com/graphics/05belch.gif, and I couldn't find a 74LS05
so
I used a 74LS04 without the pull-up resistors. It works just fine
nonetheless.
Click to expand...
Then you are lucky. When the programmer needs to verify the data, it will
drive the RB7 pin high. Had you used an open collector (LS05) the
microcontroller could just pull RB7 high or low to output a databit. By
using a '04, you drive RB7 hard to VCC which results in a high current from
RB7 if the microcontroller drives it to 0. It could potentially damage the
controller.

I'm not sure either... I'd have expected series resistors on rb6 and rb7
to handle the case when the pic wants to drive those pins as outputs while
connected top the circuit... maybe this never happens..
Click to expand...
That is very simple: the RB7 pin is bidirectional, so it is an input when
programming and an output when reading or verifying the chip. By using open
collector gates, you can drive it to '1' which means the signal is only
driven by the resistor. This in turn enables the PIC to drive the Data line
as an output. This scheme is called semi-bidirectional and is used on a lot
of microcontrollers.

Technically, only the gate that drives RB7 would have to be open collector
but that would require two IC's. By using open collectors everywhere, you
can get by with only one IC, the LS05.

Meindert
 
All those pretty colors for 220, 240 & 480 volt power wiring .....
Click to expand...
???????????

does the guage matter?
Click to expand...
Yes, each gage has a maximum ampacity at given voltage and length of run.





--
Remove "nospam" to get to me.
 
On 2005-12-06, Jasen Betts <jasen@free.net.nospam.nz> wrote:
On 2005-12-06, Dan Lenski <dlenski@gmail.com> wrote:
On Fri, 02 Dec 2005 11:43:18 -0800, PeteS wrote:

Pullup / pulldown. When applied to internal circuitry, this means there
is a pullup ( or pulldown) device inside the chip (which may be a
resistor but is more commonly a FET) which, in the absence of an input
(floating input) will pull the input to the appropriate level. A pullup
pulls high, a pulldown pulls low.

Thanks for these helpful explanations! Is there a good reason for
why there would be pull-up resistors on the OUTPUT of a gate?

many gates don't produce much curren out of their outputs when high,
abut when their output is low it's fairly well connected to ground.

I just built this microcontroller programmer,
http://www.myke.com/graphics/05belch.gif, and I couldn't find a 74LS05 so
I used a 74LS04 without the pull-up resistors. It works just fine
nonetheless. I don't understand why open-collector gates with pull-ups
were specified in the schematic... but I am a noob :)

I'm not sure either... I'd have expected series resistors on rb6 and rb7
to handle the case when the pic wants to drive those pins as outputs while
connected top the circuit... maybe this never happens..
Click to expand...
OK....

I figured it out PIC pin 13 is data is for input and output (so you can
verify that your program loaded into the chip without errors)
After a number of program-erase-program cycles the flash memory wears out
(with the Atmel chips I'm more familiar with you get abvout 1000 cycles)

with the open-collector chip when parallel port pin 17 is high 74ls05 pin
10 is also high (and not driven by the 74LS05), and the pic output can be
read back through the inverter (74LS05 pins 9 and 8) and parallel port pin 13

with a totem-pole output inverter chip with parallel pin 17 high abd the pic
output low the two chips are trying to put the opposite voltage onto the
74LS05 pin 9, which may or may not work as intended and may or may not damage
one of them.

also 74LS05 pin 6 is driving point that's pulled up to about +10V by resistors
but some current will leak back through the totem-pole output
as a result you may not be able to turn the program voltage off. (pin 4)

gotta go.

Bye.
Jasen
 
On Tue, 06 Dec 2005 13:01:39 +0100, Meindert Sprang wrote:

I used a 74LS04 without the pull-up resistors. It works just fine
nonetheless.

Then you are lucky. When the programmer needs to verify the data, it will
drive the RB7 pin high. Had you used an open collector (LS05) the
microcontroller could just pull RB7 high or low to output a databit. By
using a '04, you drive RB7 hard to VCC which results in a high current from
RB7 if the microcontroller drives it to 0. It could potentially damage the
controller.
Click to expand...
Okay, thanks for that excellent explanation, Meindert!

As far as I can tell, the reason why it works is because:

(1) the LS04 can only output about 4 mA when driving a line high (it is
always put into this state when reading from the microcontroller)
(2) the PIC model I am using can output about 25 mA per pin
(3) when the PIC drives the line low, and the LS04 drives it high, the PIC
wins

So basically I got lucky, as you said. I think I understand
open collector much better now. Is it correct to think that
one purpose of the open-collector output is to explicitly limit
the amount of current when driving the line high? As I see it, with
VDD=5V and a 10k pull-up resistor, only 0.5 mA of current will be driving
the line high if the PIC is driving it low. That would be more tolerant
of other models which can't drive so much current.

I'll be replacing that LS04 with an LS05 ASAP :) Thanks everyone for
your great explanations of this issue.

Dan
 
Dan Lenski wrote:
On Tue, 06 Dec 2005 13:01:39 +0100, Meindert Sprang wrote:


I used a 74LS04 without the pull-up resistors. It works just fine
nonetheless.

Then you are lucky. When the programmer needs to verify the data, it will
drive the RB7 pin high. Had you used an open collector (LS05) the
microcontroller could just pull RB7 high or low to output a databit. By
using a '04, you drive RB7 hard to VCC which results in a high current from
RB7 if the microcontroller drives it to 0. It could potentially damage the
controller.


Okay, thanks for that excellent explanation, Meindert!

As far as I can tell, the reason why it works is because:

(1) the LS04 can only output about 4 mA when driving a line high (it is
always put into this state when reading from the microcontroller)
(2) the PIC model I am using can output about 25 mA per pin
(3) when the PIC drives the line low, and the LS04 drives it high, the PIC
wins

So basically I got lucky, as you said. I think I understand
open collector much better now. Is it correct to think that
one purpose of the open-collector output is to explicitly limit
the amount of current when driving the line high? As I see it, with
VDD=5V and a 10k pull-up resistor, only 0.5 mA of current will be driving
the line high if the PIC is driving it low. That would be more tolerant
of other models which can't drive so much current.

I'll be replacing that LS04 with an LS05 ASAP :) Thanks everyone for
your great explanations of this issue.

Dan
Lowpower Scottky TTL is defined as having a builtin pullup current in
Click to expand...
each input ,so you dont have to add more pullup current.
Its oke to pull it up to vcc+.3 volt, anything over about 2.5V will
cause a "1".
A zero is anything below about .7 volt,so anything which can pulldown
more than a few tenth of a Milliamp,will do just fine.

3.3V logic outputs with a standard CMOS output,or any open
collector/source puldown output should interface fine with LS TTl.
 
Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sat, 03 Dec 2005 01:18:50 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

You'll not be warned.

You just did.

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and fucking well like it.
Click to expand...
Stout, please.
--
ah
 
On Wed, 07 Dec 2005 12:01:00 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and fucking well like it.

Stout, please.
Click to expand...
I'll stand any way I wish.

--
http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com

I just sent my lawyer something for his birthday. Unfortunately, he wasn't home when it went off.
 
Peter Hucker wrote:
On Wed, 07 Dec 2005 12:01:00 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and fucking well like it.

Stout, please.

I'll stand any way I wish.
Click to expand...
*snicker*
--
ah
 
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sat, 03 Dec 2005 01:18:50 -0000, ah <splifingate@gmail.com
wrote:

Peter Hucker wrote:

You'll not be warned.

You just did.

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and
fucking well like it.

Stout, please.
Click to expand...
Let me show you to the "Big and Tall" guys' shop.... ;-)

Cheers!
Rich
 
Rich Grise wrote:
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:


Peter Hucker wrote:

On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:


Peter Hucker wrote:

On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:


Peter Hucker wrote:

On Sat, 03 Dec 2005 01:18:50 -0000, ah <splifingate@gmail.com
wrote:


Peter Hucker wrote:

You'll not be warned.

You just did.

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and
fucking well like it.

Stout, please.


Let me show you to the "Big and Tall" guys' shop.... ;-)

Cheers!
Rich


Hey boys, where is the party? I want to join in,
Click to expand...
been to long since I was soaked last.
 
On Thu, 08 Dec 2005 00:34:20 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Wed, 07 Dec 2005 12:01:00 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and fucking well like it.

Stout, please.

I'll stand any way I wish.

*snicker*
Click to expand...
It's rude to point.

--
http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com

After Christmas vacation, an elementary school teacher was asking her students how they celebrated Christmas.
When she got to Sammy, whose father ran a local toy store, she said, "Sammy, since you're Jewish, I guess your family didn't celebrate Christmas."
Sammy replied, "Oh yes, we did. We all held hands and danced around the cash register singing, 'What A Friend We Have In Jesus.'
 
On Thu, 08 Dec 2005 04:13:14 -0000, Sjouke Burry <burrynulnulfour@ppllaanneett.nnlll> wrote:

Rich Grise wrote:
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:


Peter Hucker wrote:

On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:


Peter Hucker wrote:


The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and
fucking well like it.

Stout, please.


Let me show you to the "Big and Tall" guys' shop.... ;-)

Cheers!
Rich


Hey boys, where is the party? I want to join in,
been to long since I was soaked last.
Click to expand...
Anywhere in Edinburgh in the evening.

--
http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com

Two poor kids were invited by a rich kid to a swimming party at his pool.
When they were changing into their swim trunks, one turned to the other and said:
"Did you notice the small dicks on the rich kids?"
The other answered: "Yeah! It's probably because they have toys to play with!"
 
On Thu, 08 Dec 2005 05:13:14 +0100, Sjouke Burry wrote:
Rich Grise wrote:
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:
Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:
Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:
Peter Hucker wrote:
On Sat, 03 Dec 2005 01:18:50 -0000, ah <splifingate@gmail.com
Peter Hucker wrote:

You'll not be warned.

You just did.

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and
fucking well like it.

Stout, please.

Let me show you to the "Big and Tall" guys' shop.... ;-)

Hey boys, where is the party? I want to join in, been to long since I was
soaked last.
Click to expand...
Hey, just do like I do: I bring the party with me! %-}

Cheers!
Rich
 
Rich Grise, but drunk wrote:
On Thu, 08 Dec 2005 05:13:14 +0100, Sjouke Burry wrote:
Rich Grise wrote:
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:
Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:
Peter Hucker wrote:
On Sun, 04 Dec 2005 02:18:09 -0000, ah <splifingate@gmail.com> wrote:
Peter Hucker wrote:
On Sat, 03 Dec 2005 01:18:50 -0000, ah <splifingate@gmail.com
Peter Hucker wrote:

You'll not be warned.

You just did.

Don't make me come over there.

Come over here.

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and
fucking well like it.

Stout, please.

Let me show you to the "Big and Tall" guys' shop.... ;-)

Hey boys, where is the party? I want to join in, been to long since I was
soaked last.

Hey, just do like I do: I bring the party with me! %-}
Click to expand...
Easy Gents--let's not get all mushy, and stuff.

*droughts*
--
ah
 
Peter Hucker wrote:
On Thu, 08 Dec 2005 00:34:20 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Wed, 07 Dec 2005 12:01:00 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Sun, 04 Dec 2005 22:25:12 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

The helicopter will arrive shortly--I expect tea.

TEA????? Are you English or something? You will be served beer and fucking well like it.

Stout, please.

I'll stand any way I wish.

*snicker*

It's rude to point.
Click to expand...
It's rude to expose others to such ambiguity.
--
ah
 
On Fri, 09 Dec 2005 01:12:06 -0000, ah <splifingate@gmail.com> wrote:

Rich Grise, but drunk wrote:
On Thu, 08 Dec 2005 05:13:14 +0100, Sjouke Burry wrote:
Rich Grise wrote:
On Wed, 07 Dec 2005 12:01:00 +0000, ah wrote:
Peter Hucker wrote:

Stout, please.

Let me show you to the "Big and Tall" guys' shop.... ;-)

Hey boys, where is the party? I want to join in, been to long since I was
soaked last.

Hey, just do like I do: I bring the party with me! %-}

Easy Gents--let's not get all mushy, and stuff.
Click to expand...
Mushy peas all round!

*droughts*
Click to expand...
[applies water]

--
http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com

Little Johnny was sitting in class one day.
All of the sudden, he needed to go to the bathroom.
He yelled out, "Miss Jones, I need to take a piss!!"
The teacher replied, "Now, Johnny, that is NOT the proper word to use in this situation.
The correct word you want to use is 'urinate.'"
Please use the word 'urinate' in a sentence correctly, and I will allow you to go."
Little Johnny thinks for a bit, then says,
"You're an eight, but if you had bigger tits, you'd be a ten!"
 
On Fri, 09 Dec 2005 01:13:16 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Thu, 08 Dec 2005 00:34:20 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:
On Wed, 07 Dec 2005 12:01:00 -0000, ah <splifingate@gmail.com> wrote:

Peter Hucker wrote:

Stout, please.

I'll stand any way I wish.

*snicker*

It's rude to point.

It's rude to expose others to such ambiguity.
Click to expand...
It's rude to expose others to your small appendage.

--
http://www.petersparrots.com http://www.insanevideoclips.com http://www.petersphotos.com

A young Jew and an old Jew are riding on a bus in Jerusalem.
The young Jew asks, "Excuse me, sir, what time is it?"
The old Jew doesn't answer.
"Excuse me, sir," the young Jew asks again, "what time is it?"
The old Jew looks up him, but still doesn't answer.
The young Jew is puzzled, "Sir, forgive me for interrupting you all the time, but I really want to know what time it is. Why won't you answer me?"
The old Jew turns toward the young man and says, "Son, the next stop is the last on this route. I don't know you, so you must be a stranger to this land. If I answer you now, according to Jewish tradition, I must invite you to my home. You're handsome and I have a beautiful daughter. You would fall in love with her and you'd want to get married. And tell me, why would I want a son-in-law who can't even afford a fucking watch?"
 
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