18F2431 won't program or erase.

[mister_e]

Did you also tried ICSP too?

I have the same problem with PICSTART on this device here too. But not on another programmer.

I'll send a mail NOW to their tech-support to know if there's a known working solution.

[HenrikOlsson]

Wow, thanks for the effort Keith!
Too bad it didn't work, I was hoping I was doing something wrong at my end. I'm a bit suprised that Microchips own programer have problems flashing the device. I'll try the cap aproach here as well to see if I can get it to work, not that I think it will but....

Mister_e,
I did not try ICSP, never used it actually. Please let us know what you find out from the tech support. I may end up contacting them as well If I continue to have problems.

I'd really like to get this chip going....

Thanks again, both of you!
/Henrik Olsson.

[HenrikOlsson]

Hi again guys,
The help file for the PicStartPlus said to put a 1k resistor between pin 7 (AVdd) and pin 11 (RC0) on the 2431 when programing. I did that and now the device erases and blank checks OK. RTFM, RTFM, RTFM..... ;-)

I don't have the bootloader hex file with me at the moment but trying to program a blank file works now! No more errors on config fuses and such. I will try flashing it with the bootloader file when I get home tonight, I'll let you know how it works out.

Thanks again!
/Henrik Olsson.

[keithdoxey]

The help file for the PicStartPlus said to put a 1k resistor between pin 7 (AVdd) and pin 11 (RC0) on the 2431 when programing.

Where did you find that and in which help file ?

I just checked the release notes for 7.40 and 7.42 and the only reference to a resistor is

Programming PIC16F818/819 Devices
When programming a PIC16F818 or PIC16F819, you must add a 1kohm resistor between MCLR and GND. This can be placed in the socket with the device.

However in the 7.42 release notes I noticed the following...

Firmware version 4.50.01 will be available in the near future.

... hopefully that will fix some of these problems.

I did that and now the device erases and blank checks OK. RTFM, RTFM, RTFM..... ;-)

Yabba Dabba Doo

Will try it on mine later. Did you just need the resistor or did you need capacitors as well.

There I discovered that I had to order the PUM-unit from Microchip to retrofit my 1996 model PicStartPlus

I wonder if this specific problem is related to early programmers. Mine isnt quite that old but I did once replace the PIC and then later fitted the PUM unit. Not entirely sure when I got mine but the label on the bottom says

10-00157-R9
JIT980123357

So having seen lots of serial number labels over the years I am going to hazard a guess at "Jan 1998" or "1998 Week 01"

[HenrikOlsson]

Keith,
I found the info about the resistor in the file hlpPSPlus.chm in the ...MPLAB IDE\PicStartPlus folder. I tried with only the resistor and it SEEMED to work but I'll try to actually put a real file in it when I get home.

About the age of the PicStartPlus, it says in the same help file that: Some PICSTART Plus of revision R4 or earlier have been known to have problems operating with firmware OS versions 3.11 or later; however, this should not be a deterrent from purchasing a PUM if it is needed.

If a PICSTART Plus fails to work properly after installing a PUM, such as receiving communication errors or the power light will not turn on, it can returned to Microchip for replacement.

Mine is R4 (actually from -97 if your guess is correct) but yours seems to be R9 and the errors we get when programming isn't really what the help file says could be problematic, but who knows....

About this RTFM thing, the info is scattered among so many different places that I'm not suprised I missed it in the first place. There's the PBP release notes and manual, MPLAB release notes and helpfile(s), PICStartPlus help and releas notes, MCSP and MicroCodeLoader help files and release notes, PIC datasheet and reference manuals and.....

Let me know if the resistor works for you.

/Henrik Olsson.

[Acetronics2]

Hi,Keith

Have a look here :http://www.mbtronics.com/picxx.asp

very serious guys ...

Alain

[sayzer]

Hi Alain,

On that link, 12F675 price is 2,70 €.

Roughly, three times more expensive then we have here. I am sure others are also expensive, but I did not check their prices here.

I know that the gas prices are very expensive here but I am surprised that 12F675 is that much expensive in France!


Is it correct or it is for a bundle?


----------------------------------------

[keithdoxey]

Keith,
I found the info about the resistor in the file hlpPSPlus.chm in the ...MPLAB IDE\PicStartPlus folder. I tried with only the resistor and it SEEMED to work but I'll try to actually put a real file in it when I get home.

Thanks Henrik, found it now...

PICSTART Plus Limitations for PIC18F2331/2431
All power supply (Vdd and AVdd) and ground (Vss and AVss) pins must be used in order for these devices to program. PICSTART Plus will handle Vdd, Vss and AVss properly, but you must place a 1kOhm resistor between Pin 7 (AVdd) and Pin 11 in the socket with the device for proper operation. There are other devices that may require the use of all power supply and ground pins. Consult the datasheet if an unexplained programming problem occurs, such as inconsistent programming.

In your original mention of the resistor you said "between pin 7 (AVdd) and pin 11 (RC0)". the help file just mentions "Pin 11" rather than "RC0"

Looking at the pinout of the 4431, pin 11 is actually AVdd so I wonder if the resistor is because power is supplied to the wrong pins. Also the help file does not mention problems with the 4431 which also wouldnt program for me

Will experiment tonight.

Hi,Keith

Have a look here :http://www.mbtronics.com/picxx.asp

Thanka Alain but I already have the upgrade fitted.

[mister_e]

I confirm the 1K to RC0 + 1uF on Vdd/Vss (ONLY) stuff work

ICSP work as well without any care of the resistor on RC0... just the PGM pin must be loaded to GND.

Well spotted!

Another Picstart problem solved