Debugger and Writing To/Reading From EEPROM

[Guest]

Hello to All,

I would appreciate comments from members of the Forum regarding the behavior of the PCWH Debugger when writing to and reading from EEPROM. It appears to me that the Debugger is not actually writing entries to my PIC’s EEPROM but is, instead, using an area of my computer’s memory to “simulate” the PIC’s EEPROM. I would appreciate it if someone who knows would either confirm my suspicion, or explain to me what I am missing.

Here’s the setup. I am using version 4.068 of PCWH. I am using a Mach-X programmer (the Mach-X is not providing power to the PIC – a 5.0 volt power supply is connected to the breadboard where the PIC is installed).

My PIC is on a Microchip AC162055 header. This is an ICD header version of the 16F684 chip. (The regular 14-pin 16F684 does not have ICD capabilities; the AC162055 header includes a 20-pin 16F684-ICD that does have ICD capabilities.)

My program uses the “write_eeprom()” function to write a 17 element array to data EEPROM. In the Debugger, clicking the “Refresh” button on the EEPROM tab shows the data were written to EEPROM (after I have run the program). However, if I close the program and open another (to read the data from EEPROM), what appears in all of the cells of the EEPROM tab is “FF,” not the values I wrote to EEPROM in the first program.

It appears to me that the Debugger does not actually “flash” values into the PIC’s onboard EPROM. Instead, it looks like it is “simulating” EEPROM writes. Is this the case or am I missing something?

Thank you in advance for your courtesy.

Bill

BTW - what is the deal with posting on the forum? I am a registered user but can't post using my user name.

[Guest]

Well, I answered my own question (I think). I wrote the above post when I was out of town and had limited PIC supplies with me. When I returned to the shop today I flashed my program into a 16F684 and it ran fine. Data were stored in EEPROM and, after the power was turned off and back on, were available for use ny the PIC's program.

So, I'm going to conclude that the Debugger DOES NOT actually flash EEPROM when connected to a 16F684-ICD. And I'll operate from that same assumption (may be scarey!) when I use the Debugger with other PICs.

Cheers!

Bill