burning data to eeprom during cpu programming

[Bob Knipper]

Greetings, I am writing a program for the 16f628. Is their a command in GCB that
will create a hex file that ,during programming the cpu, will load data into eeprom.
I want to have data in eeprom that I can during the program read and modify.
Thanks Bob

[Anonymous]

I never figured out how to do this myself. So instead, I simply compile the code, then put the necessary .DE statements in the assembler code, and conclude by assembling.

Thomas Henry

[Anobium]

A great question. You can use 'EPWrite location, data' (see the help file) but this function is byte by byte.

@Thomas Henry can you post an example of your approach?

I would like to have a function as follows using GCB not ASM within the Public function. An EEPROM function that take a string or data sequence and write to the EEPROM. I we have EPWrite location, data but has someone written a food function?

Anobium

EEPROM 0,(“Hello World”): 'save values in EEPROM

main:
for loopvar = 0 to 10 ; start a loop
read loopvar, indata ; read value from EEPROM
hserprint in data ; transmit to serial LCD module
next loopvar ; next character

[Hugh Considine]

There's no nice way to do this, but there is a trick with the Table statement that you can use. If the compiler is told to store a data table in "Data" memory, it will store it in the EEPROM. Here is some example code:

#chip 16F628

'Read table item
'Must use ReadTable and a variable for the index, or the table won't
'be downloaded.
TableLoc = 2
ReadTable TestDataSource, TableLoc, SomeVar

'Write to table (example, can change)
EPWrite 1, 45

'Table of values to write to EEPROM
'EEPROM location 0 will store length of table
'Subsequent locations will each store a value
Table TestDataSource Store Data
    12
    24
    36
    48
    60
    72
End Table

[Anobium]

Cool. OK. Very good.

Can you clarify? Have I got the wrong end of the stick?
1. When I tried your example. I got one byte written to the EEPROM not the table contents. I got value 0x2d at location 02. Does this mean the table is not written out? Is this dependent on a file I don't have?
2. The variable 'somevar'. It is essentially a nul variable? Meaning it could be any variable?
3. I just found the table values... at location 0x1800 (for the device 16f1825), so, the table is in program memory not EEPROM?
4. But, in my simulator of a 16f628 it is located in EEPROM. So is this solution pic dependent? or, the addressing to the EEPROM for specific devices required?

[Bob Knipper]

Thanks all, for the help. I had been loading the hex file into my programmer program.
'WIN PIC PROGRAMMER' and manually entering data. then re-saving the file.
Kind of a convoluted but works. Bob
Tried both ideas, worked great

[Anonymous]

Thanks for the tip, Hugh. The real hassle with what you propose is that each datum must appear on a separate line. It would be so cool if that could be overridden somehow, allowing the compiler to parse entire horizontal lines, and even permitting string literals. For example:

TABLE TestDataSource Store Data
"Here's a message."
END TABLE

Thomas Henry

[Anobium]

HUGH can you check this statement: This only works currently with current EEPROM memory devices. This means you must verify your device to use this technical solution.