I2C with External Eeprom

[skimask]

DEFINE OSC 8
INCLUDE "modedefs.bas" 
@ DEVICE INTRC_OSC
@ DEVICE MCLR_OFF
@ DEVICE PROTECT_OFF
@ DEVICE CPD_OFF
@ DEVICE LVP_OFF
@ DEVICE BOD_OFF
@ DEVICE PWRT_OFF
@ DEVICE WDT_OFF
DEFINE DEBUG_REG PORTB  
DEFINE DEBUG_BIT 7
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 1
osccon=$7e:cmcon=7:adcon1=$80:ansel=1:adcon0=$c1:porta=0:portb=0:trisa=1
trisb=7:sda var portb.0:scl var portb.1:addr var word:dat var byte
dat2 var byte:ctw con $a0
start:     dat=dat+1:addr=addr+1
i2cwrite sda,scl,ctw,addr.highbyte,addr.lowbyte,[dat]:pause 10
debug "Wrote: ",dec addr," with ",dec dat,13,10
i2cread sda,scl,ctw,addr.highbyte,addr.lowbyte,[dat2]
debug " Read: ",dec addr," val: ",dec dat2 , 13 , 10
if dat = dat2 then
debug "Write/Read Successful at ",dec5 addr," with ",dec3 dat,13,10
else
debug "Write/Read Error at ",dec5 addr,"-Wrote:",dec3 dat," - Read:",dec dat2,13,10
endif
pause 500:goto start
END

OR un-COLONized...

DEFINE OSC 8
INCLUDE "modedefs.bas" 
@ DEVICE INTRC_OSC
@ DEVICE MCLR_OFF
@ DEVICE PROTECT_OFF
@ DEVICE CPD_OFF
@ DEVICE LVP_OFF
@ DEVICE BOD_OFF
@ DEVICE PWRT_OFF
@ DEVICE WDT_OFF
DEFINE DEBUG_REG PORTB  
DEFINE DEBUG_BIT 7
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 1
osccon = $7e
cmcon = 7
adcon1 = $80
ansel = 1
adcon0 = $c1
porta = 0
portb = 0
trisa = 1
trisb = 7
sda var portb.0
scl var portb.1
addr var word
dat var byte
dat2 var byte
ctw con $a0

start:
dat = dat + 1
addr = addr + 1
i2cwrite sda , scl , ctw , addr.highbyte , addr.lowbyte , [ dat ]
pause 10
debug "Wrote: " , dec5 addr , " with " , dec3 dat , 13 , 10
i2cread sda , scl , ctw , addr.highbyte , addr.lowbyte , [ dat2 ]
debug " Read: " , dec5 addr , " val: " , dec3 dat2 , 13 , 10
if dat = dat2 then
debug "Write/Read Successful at " , dec5 addr , " with " , dec3 dat , 13 , 10
else
debug "Write/Read Error at " , dec5 addr , "-Wrote:" , dec3 dat , " - Read:" , dec dat2 , 13 , 10
endif
pause 500
goto start
END

[ruijc]

Hi skimask,

i'm pleased to say that your code worked. Thank you very much for your help

Will re-write my entire code from scratch.

I have some notes here and i will see what happens.

.

[skimask]

Hi skimask,
i'm pleased to say that your code worked. Thank you very much for your help
Will re-write my entire code from scratch.
I have some notes here and i will see what happens.
.

Really?
That's amazing...because I did a quick search a couple days ago for 24LC512 here on THESE forums and, except for COLON-izing the one listing, practically did a cut-and-paste.
Search engine must've been broken that day...huh?

[ruijc]

I guess i missed that one, sorry.

But thanks anyway for your help

.

[ruijc]

Greetings,

While reviewing my code i changed the I2C lines from :

I2Cread SDA,SCL,CTW,mem,[x]

to

I2Cread SDA,SCL,CTW,mem.highbyte,mem.lowbyte,[x]

to make it work.

Sorry if i'm a bit stubborn ( just trying to learn ), but i re-made ( yes... re-made ) the search and as before almost every one mentions the I2C lines as follows :


I2cwrite SDA,SCL,CONTROL,ADDR,[DATA]

Posts like:
http://www.picbasic.co.uk/forum/show...hlight=24lc512

http://www.picbasic.co.uk/forum/show...hlight=24lc512

http://www.picbasic.co.uk/forum/show...hlight=24lc512

Including melanie's post

http://www.picbasic.co.uk/forum/showthread.php?t=587

The only one that mentions to separate the address in high and low somehow did not worked in that case

http://www.picbasic.co.uk/forum/show...hlight=24lc512


My question is just to try to understand

Why is that the i2c line ( I2cwrite SDA,SCL,CONTROL,ADDR,[DATA] ) works with other pics ( yes...all my programs with 12F675 work ) and with the 16F88 does not ? Why with this pic i need to have the address separated with high and low byte ?

Also ( question for skimask )
In post # 7 you mention :

'cause I see a few flaws in your logic in the code written a few posts back.

Can you please point where the flaws are so i can take a look at them ?

Thanks

[skimask]

Why is that the i2c line ( I2cwrite SDA,SCL,CONTROL,ADDR,[DATA] ) works with other pics ( yes...all my programs with 12F675 work ) and with the 16F88 does not ? Why with this pic i need to have the address separated with high and low byte ?

Quite frankly, if it works, who cares?
Actually, I don't remember the answer to that at the moment. I'll remember eventually...

Also ( question for skimask )
In post # 7 you mention :

'cause I see a few flaws in your logic in the code written a few posts back.

Can you please point where the flaws are so i can take a look at them ?
Thanks

You'll figure it out... Suffice to say there's just MUCH better ways to do some things, more reliable, faster, longer, stronger, and so on...

[ruijc]

I've had to make some changes in my logic to work with the new I2C lines ( low/high address ) but still maintained the generic structure.

This was my priority #1

After checking if it works will study on those flaws .

I undestand your point of "if it works, who cares", but if we leave things like that we will never get to improve the codes to be more reliable, faster and shorter

Dont you agree ?

In the mean time, if you remember please let me know

Thanks again
.