bizarre problem 16f628-20/P -?

[phoenix_1]

I have bizarre problem to make work 16F628-20/P @20MHz.
I was probe with cap =10pF to 27pF + XTAL 20 and 4 MHz , and also to config internal 4MHz osc but it don't want work.
When I program it and clear all is ok.Verificate of HEX is to OK 100%.
In that PCB board I was probe 16F628-04/P and also 16F84A at 4 and 20 MHz and that two work 100% OK.
Is possible to a NEW pcs of 16F628-20/P want to program flash mem but don't want work ?

Regards Robert

[Archangel]

Hi Phoenix_1,
Unless you are making secret Government military hardware (unlikely given your experience level), You will be light years ahead of the game, if you were to post your code, especially given your command of the English language, I am sure it is much better than my command of Yugoslavian, I am not Knocking you, just trying to be helpful.<br> That said, Does any part of your routine operate? If not, I would suspect an error in the Config Fuse settings, or a hardware problem like corroded breadboard, that is why the Skimask ALWAYS uses a blinky in his circuits. So as to see if life exists inside the &micro;Controller. I think it is a good idea, you can always remove it after you get the device working.

[phoenix_1]

Hi Phoenix_1,
Unless you are making secret Government military hardware (unlikely given your experience level), You will be light years ahead of the game, if you were to post your code, especially given your command of the English language, I am sure it is much better than my command of Yugoslavian, I am not Knocking you, just trying to be helpful.<br> That said, Does any part of your routine operate? If not, I would suspect an error in the Config Fuse settings, or a hardware problem like corroded breadboard, that is why the Skimask ALWAYS uses a blinky in his circuits. So as to see if life exists inside the &micro;Controller. I think it is a good idea, you can always remove it after you get the device working.

Yes blinky is always good and I use it all the time and couple metods too but with these
&micro no metods work and after all time what I was spend with it end coming soon and buy couple new maybe will fix that problem :-((

Interest is at that pcs to programing go good and erase too.
If someone want to test it I will send it via mail to him for probe ...

Just give me to know who want to probe make it work :-)

Regards Robert

[skimask]

Well, again, let's see some code, some configuration information, what kind of programmer, software, maybe some schematic information, power supply, anything, etc.

[phoenix_1]

Well, again, let's see some code, some configuration information, what kind of programmer, software, maybe some schematic information, power supply, anything, etc.

@ DEVICE pic16F628, HS_OSC
' ---- High Speed Oscilator
@ DEVICE pic16F628, WDT_OFF
' ---- Watchdog Timer=OFF
@ DEVICE pic16F628, BOD_ON
' ---- Brown-Out Detect
@ DEVICE pic16F628, LVP_OFF
' ---- Low-Voltage Programming=OFF
@ DEVICE pic16F628, MCLR_ON
' ---- Reset Pin=Internal
@ DEVICE pic16F628, PWRT_ON
' ---- Power-On Timer=Disabled
@ DEVICE pic16F628, CPD_OFF
' Data Memory Code Protect
' Set to CPD_OFF for Development Copy
@ DEVICE pic16F628, PROTECT_OFF
' Program Code Protection 

'MCLR pin is pullup at 5V via 4K7 
'external XTAL @20MHz and two cap (I was probe from 10pF to 27pF)
'portb.1 to led via 330 ohm and 330 ohm to GND (led is low current green)
'when I put in same socket PIC 16F628-04/P and change XTAL to 4MHz and 2x27p LED
'blinky OK and if I change in that socket 16F84A-20/P and use XTAL 20MHz and 2x27p
'it blinky 100% OK. THAT MEAN THAT PROTO PCB is OK ........
'these code is for 16F628-20/P @20MHz HS osc
'programmer is EPIC programer and work fine for me ;-)

define osc 20
CMCON = 7          ' PortA = digital I/O
VRCON = 0          ' Disable A/D Voltage reference

low portb.1
pause 250

loop:
high portb.1
pause 1000
low portb.1
pause 1000
goto loop
end

[paul borgmeier]

Something to try ....
remove (carefully unsolder?) the LED and see if pin goes high low high with a meter. If this works then reconnect up your LED and add decoupler Cap close to Vdd (10uF or similar).

[phoenix_1]

Something to try ....
remove (carefully unsolder?) the LED and see if pin goes high low high with a meter. If this works then reconnect up your LED and add decoupler Cap close to Vdd (10uF or similar).

Thank's friend,
I was probe many trick's nothing want to work,simply I am confused....
Is some posibility to someone manufacture clone of PicMicro or something same ???
On first look it same signature like other on other PicMicro what I have in colection..
It is not important to me to I make it work and sale in some my hardware but it very interest for me to I find what is it why...etc.
I was probe to config it with internal osc at 4MHz and same problem too.
Now I go to get frquency meter and I will post if is osc activity on it ?!

[Archangel]

Thank's friend,
I was probe many trick's nothing want to work,simply I am confused....
Is some posibility to someone manufacture clone of PicMicro or something same ???
On first look it same signature like other on other PicMicro what I have in colection..
It is not important to me to I make it work and sale in some my hardware but it very interest for me to I find what is it why...etc.
I was probe to config it with internal osc at 4MHz and same problem too.
Now I go to get frquency meter and I will post if is osc activity on it ?!

Hi Phoenix,
I am having a little trouble with the use of the word "probe" As I understand this word, it is when you put the "test probe" of your meter on a voltage source or when your doctor pokes you looking for a tender spot, if you would please elaborate a little you would be helpful.
As to your code: Verify it is a 16F628 and not a 16F628A correct?
Now,

CMCON = 7          ' PortA = digital I/O

incorrect, cmcon = 7 ' turn off analog comparators

'when I put in same socket PIC 16F628-04/P and change XTAL to 4MHz and 2x27p LED
'blinky OK and if I change in that socket 16F84A-20/P and use XTAL 20MHz and 2x27p
'<font color=red>it blinky 100% OK. THAT MEAN THAT PROTO PCB is OK ........</font color>
'these code is for 16F628-20/P @20MHz HS osc

Proto boards are loss-ey, which is to say, using them is much like installing a bunch of unwanted capacitors, the connections are often poor. If you are using crystals instead of resonators, you might try reducing/not increasing the value as you go up in frequency, even try it without the caps (on the breadboard only), as I said before, the breadboard adds a bunch of extra capacitance to the circuit. Yes it is possible you got a hold of a counterfeit
PIC, although somewhat unlikely. Keep your wiring to the crystal very, very short. Anything attached to the crystal ports will load down the oscillator and keep it from working.

[phoenix_1]

Today I was get some time for new test and after measure with frequency counter at osc out pin there is no frequency,interest is that to intosc not work too,after probe to put clock via osc in from high precise clock from 4 - 20 Mhz and couple more probe pic not work definitly becouse osc part of chip is in problem.
I was get in meddle time new 16F628-20/P and in same PCB it work 100% correct.
Some time you can buy new bad picmicro :-))
That is finish of my reasearch about that problem.

Best regards
Robert

[skimask]

That is finish of my reasearch about that problem.
Robert

So everything is good now?

[phoenix_1]

So everything is good now?

Hi skimask,
U was give me many good examples many time,and thank's anyway.
About that pcs of 16F628 @20 MHz it go to garbage but it was interest to find why
it don't want work.(becouse it osc part of chip is not good!)
In same PCB now work other 16F628-20/P very nice.

Regards to all and see you here with some other question or problem or better with some
good project from me as share thing for all.

Robert