Internal EEPROM Read/write Addressing Errors with 18F PIC's

[atillotson]

Hi Melanie,
I was wondering if you could recommend a way to read an EE with an address above 255. It appears that the Read function is limited to 1 byte addressing. Even though I declare it a word. Have you found this to be true? F.Y.I. I am using 18f2620, And loving it.

Thanks ash
Sorry to bring up an old post.

[mister_e]

it will work if you declare the Address variable as a word sized.

[atillotson]

Hi Mr. E,
I tried that but it did not work. It still loops back after address 255.

I preload My eeprom with the EEPROM *reserved word

eeprom 192,["11"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 208,["12"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 224,["13"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 240,["14"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 256,["15"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 272,["16"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 288,["17"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]
eeprom 304,["18"," "," "," "," "," "," "," "," "," "," "," "," "," "," "," "]

Im sending each line to an lcd and it works fine but i cannot reach EEPROM 256. Even though my address is 256 or above. and again my address varible is a WORD, not a BYTE.



Thanks Ash

[atillotson]

Oh, Well guess what?

ReadMenuData:
x = 2
for Z = Index4 to Index4 + 15
read Z,sendlcd[x]
x = x + 1
next Z
return

Index4 is a word like i said but Z was a byte.
I changed it to a word and wha-la

Thanks for your help.
That was a really stupid mistake on my part sorry for your troubles.

ashman

[mytekcontrols]

Hi Melanie,

Just thought I'd throw in my 2 cents on this topic. If someone wants to preload the EEprom during the programming phase using PBP's DATA command, there is a PIC18F series problem. Dummy bytes (0) need to be inserted, and the address needs to be doubled (see below).

DATA @0,$08,0,$FE,0,$0F     ' ATTR #00
DATA @6,$03,0,$FE,0,$0F     ' ATTR #01
DATA @12,$02,0,$80,0,$0F    ' ATTR #02
DATA @18,$04,0,$0E,0,$0C    ' ATTR #03

Although this looks kinda weird, it will compile properly into the EEprom. This is only a problem with the preload function, and only with the PIC18F series (as far as I know).

This is a known bug by MEL, and they have acknowledged its existance.

[Melanie]

The 18F EEPROM problem was fixed in v2.45 and with the latest releases of MPLAB (MPASM). You need to upgrade BOTH. See very first post on this thread.

[mytekcontrols]

Melanie,

Not to say that you aren't having success, and yes I did read your original post, and no I can't run your example because I have no LCD. However I do run a rather extensive EEprom preload of my own, and it doesn't work if I use sequential addressing with the DATA command.

Here is my system:

PBP ver 2.45A
Epic ver 2.44
MPASM ver 4.01
MicroCode Studio Plus ver 2.2.1.1
Windows 2000 Professional

Here is the code that does work (non sequential addressing w/dummy bytes):

'Text Generator 0 - Color and Enhanced Feature Attributes

DATA @0,$00,0,$FE,0,$0F     ' ATTR #00
DATA @6,$00,0,$FE,0,$0F     ' ATTR #01
DATA @12,$00,0,$80,0,$0F    ' ATTR #02
DATA @18,$00,0,$0E,0,$0C    ' ATTR #03
DATA @24,$00,0,$8E,0,$0F    ' ATTR #04
DATA @30,$00,0,$70,0,$0C    ' ATTR #05
DATA @36,$00,0,$F0,0,$0F    ' ATTR #06
DATA @42,$00,0,$7E,0,$0C    ' ATTR #07
DATA @48,$00,0,$48,0,$0E    ' ATTR #08
DATA @54,$00,0,$B0,0,$0F    ' ATTR #09
DATA @60,$00,0,$28,0,$0C    ' ATTR #10
DATA @66,$00,0,$16,0,$0F    ' ATTR #11
DATA @72,$00,0,$30,0,$0C    ' ATTR #12
DATA @78,$00,0,$9E,0,$0C    ' ATTR #13
DATA @84,$00,0,$28,0,$0C    ' ATTR #14
DATA @90,$00,0,$28,0,$0C    ' ATTR #15

'Text Generator 1 - Color and Enhanced Feature Attributes

DATA @96,$00,0,$FE,0,$0F    ' ATTR #00
DATA @102,$00,0,$FE,0,$0F   ' ATTR #01
DATA @108,$00,0,$80,0,$0F   ' ATTR #02
DATA @114,$00,0,$0E,0,$0C   ' ATTR #03
DATA @120,$00,0,$8E,0,$0F   ' ATTR #04
DATA @126,$00,0,$70,0,$0C   ' ATTR #05
DATA @132,$00,0,$F0,0,$0F   ' ATTR #06
DATA @138,$00,0,$7E,0,$0C   ' ATTR #07
DATA @144,$00,0,$48,0,$0E   ' ATTR #08
DATA @150,$00,0,$B0,0,$0F   ' ATTR #09
DATA @156,$00,0,$28,0,$0C   ' ATTR #10
DATA @162,$00,0,$16,0,$0F   ' ATTR #11
DATA @168,$00,0,$30,0,$0C   ' ATTR #12
DATA @174,$00,0,$9E,0,$0C   ' ATTR #13
DATA @180,$00,0,$28,0,$0C   ' ATTR #14

'Text Generator 0 - Highlight, lowlight, and shadow color attributes

DATA @186,$FF,0,$01         ' HighLight
DATA @190,$DB,0,$00         ' LowLight1
DATA @194,$49,0,$00         ' Lowlight2/Shadow/Border

'Text Generator 1 - Highlight, lowlight, and shadow color attributes

DATA @198,$FF,0,$01         ' HighLight
DATA @202,$DB,0,$00         ' LowLight1
DATA @206,$49,0,$00         ' Lowlight2/Shadow/Border

'Horizontal and Vertical Start Position

DATA @210,$10,0,$08         ' Horizontal - Vertical Offset

'Overlay Hue Setting

DATA @214,$76               ' Hue (Text Generator 2 - Dac4)

'Fader Transparency and Time variables

DATA @216,$63,0,$00         ' T_Level and B_Level
DATA @220,$32,0,$32         ' UP_Time and DN_Time

'RTCC Time and Date Mode variables

DATA @224,$00,0,$00         ' TimeMode and DateMode

And here is the code that doesn't work (sequential addressing):

'Text Generator 0 - Color and Enhanced Feature Attributes

DATA @0,$00,$FE,$0F     ' ATTR #00
DATA @3,$00,$FE,$0F     ' ATTR #01
DATA @6,$00,$80,$0F     ' ATTR #02
DATA @9,$00,$0E,$0C     ' ATTR #03
DATA @12,$00,$8E,$0F    ' ATTR #04
DATA @15,$00,$70,$0C    ' ATTR #05
DATA @18,$00,$F0,$0F    ' ATTR #06
DATA @21,$00,$7E,$0C    ' ATTR #07
DATA @24,$00,$48,$0E    ' ATTR #08
DATA @27,$00,$B0,$0F    ' ATTR #09
DATA @30,$00,$28,$0C    ' ATTR #10
DATA @33,$00,$16,$0F    ' ATTR #11
DATA @36,$00,$30,$0C    ' ATTR #12
DATA @39,$00,$9E,$0C    ' ATTR #13
DATA @42,$00,$28,$0C    ' ATTR #14
DATA @45,$00,$28,$0C    ' ATTR #15

'Text Generator 1 - Color and Enhanced Feature Attributes

DATA @48,$00,$FE,$0F    ' ATTR #00
DATA @51,$00,$FE,$0F    ' ATTR #01
DATA @54,$00,$80,$0F    ' ATTR #02
DATA @57,$00,$0E,$0C    ' ATTR #03
DATA @60,$00,$8E,$0F    ' ATTR #04
DATA @63,$00,$70,$0C    ' ATTR #05
DATA @66,$00,$F0,$0F    ' ATTR #06
DATA @69,$00,$7E,$0C    ' ATTR #07
DATA @72,$00,$48,$0E    ' ATTR #08
DATA @75,$00,$B0,$0F    ' ATTR #09
DATA @78,$00,$28,$0C    ' ATTR #10
DATA @81,$00,$16,$0F    ' ATTR #11
DATA @84,$00,$30,$0C    ' ATTR #12
DATA @87,$00,$9E,$0C    ' ATTR #13
DATA @90,$00,$28,$0C    ' ATTR #14

'Text Generator 0 - Highlight, lowlight, and shadow color attributes

DATA @93,$FF,$01        ' HighLight
DATA @95,$DB,$00        ' LowLight1
DATA @97,$49,$00        ' Lowlight2/Shadow/Border

'Text Generator 1 - Highlight, lowlight, and shadow color attributes

DATA @99,$FF,$01        ' HighLight
DATA @101,$DB,$00       ' LowLight1
DATA @103,$49,$00       ' Lowlight2/Shadow/Border

'Horizontal and Vertical Start Position

DATA @105,$10,$08       ' Horizontal - Vertical Offset

'Overlay Hue Setting

DATA @107,$76           ' Hue (Text Generator 2 - Dac4)

'Fader Transparency and Time variables

DATA @108,$63,$00       ' T_Level and B_Level
DATA @110,$32,$32       ' UP_Time and DN_Time

'RTCC Time and Date Mode variables

DATA @112,$00,$00       ' TimeMode and DateMode

I have compiled it both ways several times, and the sequential addressing example fails to work every single time (when I view the configuration menu that is part of my main program, I can see that the EEprom data is all messed up, also the video characteristics which are based on this data do not function properly).

I have also read the readme files that came with PBP 2.45, and no where is it mentioned that the EEprom problem was fixed in this version. However on the MEL upgrade page under the PBP ver 2.44 it lists: Changes PIC18Fxxxx DATA and EEPROM to allow odd locations (This would seem to suggest that the problem was fixed in ver 2.44 and not in ver 2.45, although the wording is strange).

Once again, I'm not saying you are wroung, but please tell me why you think it doesn't work in my situation.

Thank you,