Writing 2 bytes to EEPROM

wuchy143

Member

• Oct 24, 2010

• #1

Hi,

I need to write a 2 byte number to Esquared. For example I'm able to write the first 8 bits but am confused on how to write the first 8 bits and also tell the microcontroller to write the more significant byte as well. I"m using the PIC12F675 using HIgh Tech C lite. Any thoughts?

Thanks

-mike

 

birdman0_o

Active Member

• Oct 24, 2010

• #2

Do you mean I2C instead of Esquared?

 

wuchy143

Member

• Oct 24, 2010

• #3

Nope. I'm referring to the 128bytes of EEPROM available on the PIC12F675

 

birdman0_o

Active Member

• Oct 24, 2010

• #4

Just write the lower byte, then shift your number over to the right 8 times then write that.

 

wuchy143

Member

• Oct 24, 2010

• #5

lol. Thanks. Sometimes I feel like a box of hammers

 

wuchy143

Member

• Oct 24, 2010

• #6

birdman,

I got this to work fine. Though, when I try and read it back from the EEPROM I do it the same way that I wrote it but this is what happens. So I read in the most significant byte. Shift it over 8 times in my 16 bit variable "hour". Then i read the lower byte from EEPROM set that equal to hour but that clears hour to just the lower byte and blows away the upper byte. hmmmm

 

wuchy143

Member

• Oct 24, 2010

• #7

Figured it out. I just add what's in the EEDATA register and what's already in hour after I read the least significant byte. Works great now

 

birdman0_o

Active Member

• Oct 24, 2010

• #8

be careful about shifting the carry

 

Last edited: Oct 24, 2010

wuchy143

Member

• Oct 25, 2010

• #9

Thx.

I checked out your webpage. you got some pretty cool projects up there. Do you do everything in assembly?

 

birdman0_o

Active Member

• Oct 25, 2010

• #10

Yes, I do love my op codes ever so much! I've learned C and Java at school and C# on my own as well as assembly. Assembly is what I started with, but I love it's simplicity and it's always a challenge so I always code with it