Thursday, December 6, 2007

[piclist] Re: 12F675 Startup Problems

Hi,
you may try to bypass VDD & VSS by an 100nF capacitor as close as
possible to pin 1 & 8. Then don't connect directly pin 1 to 4, but put
a resistor 100K from pin 1(VDD) to pin 4 (MCLR) and a capacitor 100nF
from pin 4 to pin 8 (VSS).
Best regards

--- In piclist@yahoogroups.com, "kg4pid" <kg4pid@...> wrote:
>
> I'm using a serial routine on a 12F675 and started by sending out the
> word "HELLO" over and over. Funny thing is while it's powered on I get
> nothing out, but the instant I remove power it sends out 10 or 11
> characters. The filter cap is powering it for that fraction of a
> second. The circuit is being powered by a 9V battery with a 78L05 to
> regulate it at 5V. My meter reads 4.99v at the pic chip. A logic probe
> connected to the output blinks the whole time it is powered up which
> should mean that its sending something. I had to include this bit of
> code at the very beginning before I got anything at all.
> call 0x3FF ; Retrieve Factory Calibration
> BANKSEL OSCCAL ; BANK1
> movwf OSCCAL
>
> Anyone have any ideas as to what might cause a problem like this?
>
> Thanks, Max
>

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Fashion News

What's the word on

fashion and style?

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Drive Traffic

Sponsored Search

can help increase

your site traffic.

.

__,_._,___

[piclist] Re: USART Transmit Issue

It sounds like a power up problem.

It could be the transmit pin is at a zero before the first byte is sent
causing a recieve error at the PC.

Might be worth putting a pullup on the TX pin.

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Odd News

You won't believe

it, but it's true

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Sitebuilder

Build a web site

quickly & easily

with Sitebuilder.

.

__,_._,___

[piclist] Re: Re: PROTEL or EAGLE PCB-CAD - comparisons ???


It should be on the PIC datasheet !

Do a search at www.microchip.com

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Get it all here

Breaking news to

entertainment news

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Best of Y! Groups

Discover groups

that are the best

of their class.

.

__,_._,___

[piclist] Re: RS232 serial communication problems with 18F458


I usually start by sending out 55H on the transmit pin and scope it to see what the actual bit timing is.
Once the transmit is correct the receive just follows on.

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Fashion News

What's the word on

fashion and style?

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Parenting Zone

Your home for

parenting information

on Yahoo! Groups.

.

__,_._,___

[piclist] Re: [ee:] EAGLE PCB-CAD

You need a gerber viewer to check the output files.

GCPREVUE is free.

I didnt buy eagle but bought pcbcad30 and that already comes with its own gerber viewer.

I was a bit perturbed at you finding 3 hole sizes where only one was used.

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Odd News

You won't believe

it, but it's true

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Fitness Challenge

on Yahoo! Groups

Get in shape w/the

Special K Challenge.

.

__,_._,___

[piclist] Re: 12F675 Startup Problems

Are you going back to bank 0 after the osccal is set ?

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Get it all here

Breaking news to

entertainment news

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Dog Groups

on Yahoo! Groups

Share pictures &

stories about dogs.

.

__,_._,___

[piclist] 12F675 Startup Problems

I'm using a serial routine on a 12F675 and started by sending out the
word "HELLO" over and over. Funny thing is while it's powered on I get
nothing out, but the instant I remove power it sends out 10 or 11
characters. The filter cap is powering it for that fraction of a
second. The circuit is being powered by a 9V battery with a 78L05 to
regulate it at 5V. My meter reads 4.99v at the pic chip. A logic probe
connected to the output blinks the whole time it is powered up which
should mean that its sending something. I had to include this bit of
code at the very beginning before I got anything at all.
call 0x3FF ; Retrieve Factory Calibration
BANKSEL OSCCAL ; BANK1
movwf OSCCAL

Anyone have any ideas as to what might cause a problem like this?

Thanks, Max

__._,_.___
to unsubscribe, go to http://www.yahoogroups.com and follow the instructions
Recent Activity
Visit Your Group
Yahoo! News

Kevin Sites

Get coverage of

world crises.

Yahoo! Finance

It's Now Personal

Guides, news,

advice & more.

Drive Traffic

Sponsored Search

can help increase

your site traffic.

.

__,_._,___