Olimex Support Forum

Microcontrollers => PIC => Topic started by: ybosco on October 30, 2014, 08:59:09 PM

Title: PIC-KIT3 doesn't see PIC18F2455
Post by: ybosco on October 30, 2014, 08:59:09 PM
Strange thing...
In March I developed a circuit comprised PIC18F2455-I/SP. The circuit functioned well.

Then the new PCB was developed. The circuit is the same. The only difference is that the controller is PIC18F2455-I/SO.

And when I tried to connect PIC-KIT3 to the PCB I received a message that read the following:

PICkit 3 detected
Connecting to PICkit 3...
Firmware Suite Version...... 01.32.10
Firmware type......................PIC18F
PICkit 3 Connected.
PK3Err0045: You must connect to a target device to use PICkit 3.

I checked everything, the wires, the circuit, the components but vainly.
Unfortunately I can't use the old PCBs to compare the results.

I have 2 new PCBs. The result is the same for both.

When I tried to connect some another controller, PIC16F785, I get the following result:

PICkit 3 detected
Connecting to PICkit 3...
Firmware Suite Version...... 01.28.90
Firmware type......................Enhanced Midrange
Downloading AP...
AP download complete
Running self test...
Self test completed
Firmware Suite Version...... 01.28.90
Firmware type......................Midrange
PICkit 3 Connected.
Target Detected
Device ID Revision = 00000003

So it looks like PIC-KIT3 is in order. But I see the difference between the firmware versions. I don't know how it affects the PIC-KIT3 functionality.

I would be very grateful for any help.
Title: Re: PIC-KIT3 doesn't see PIC18F2455
Post by: JohnS on October 30, 2014, 09:57:14 PM
I suspect a PCB or soldering fault with one or more of the vital pins, or a wrong component on them.

Such problems can take real determination to find.

John
Title: Re: PIC-KIT3 doesn't see PIC18F2455
Post by: ybosco on October 31, 2014, 08:37:58 AM
I checked carefully every wire. Nothing wrong.

I can add one strange detail.

When I pullup /MCLR to VDD with 10k I can see at this pin a high logic level (very close to VDD) after putting a power supply. But when I connect PIC-KIT3 to the board I can see there only 1 V with some high frequency noicelike spikes.

Can such problem be caused by a broken chip? I doubt because if /MCLR circuit is burnt then the high level will not be seen. There will be another voltage. Isn't it?
Title: Re: PIC-KIT3 doesn't see PIC18F2455
Post by: ybosco on October 31, 2014, 08:55:00 AM
I seem to find what's wrong.

I change not only the controller package but a programmer plug also. And the plug has an opposite pin numeration. But it needs checking anyway.

I'll make it immediately.

......................................................

After interchanging the wires I received at last the following:

PICkit 3 detected
Connecting to PICkit 3...
Firmware Suite Version...... 01.28.90
Firmware type......................PIC18F
PICkit 3 Connected.
Device ID Revision = 00000007

It's OK now.

There is such connector as CI11xx. This connector type has very small pitch, as small as 1 mm. There are 2 types of the connector: vertical (V) and horisontal (H).
Be watchfull, V-type has an opposite numbering versus H-type if you look at the connector from the top but same footprint.