EEPROM help

[Srigopal007]

Why is it that Writing to EEPROM takes longer than reading from EEPROM.

Writing a BYTE to EEPROM takes around 4ms with a 20Mhz, While READING a BYTE from EEROM takes like 3 microsec.

cant explain why this is the case. any way I can reduce the time it takes to write to EEPROM?

srig

[mister_e]

Are you talking about the internal EEPROM of a PIC or an external one?

If the internal one, how did you measure it? By interrupt or by testing with pauses?

Are you using WRITE and READ ? If so what about if you use some assembly lines (they're mostely provide in datasheet)

Some external can be much faster than this IMO.

[Srigopal007]

I am using the WRITE and READ command in the pbp compiler. I us MPLAB , where you can actually debug your code line per line and to see how long each command takes. by using the stopwatch, embedded in the GUI. and that is pretty well calculated timing they use. anyway I was just curious on why it takes soo long to write .. then read.. becasue I am noticing flickering at the output because of this. was wondering how I can get around this.

please help!!

srig

[mister_e]

what is your actual code ?

[NavMicroSystems]

I guess it's more a matter of "physics" than a matter of coding.

I'll try to dig out a document that explains it (if I find time to)

[Bruce]

Look in the datasheet for the device you're using.

Electrical Specifications
....DC Characteristics
........ Data EEPROM Memory

EEPROM Erase/Write cycle time is from 4 to 8mS. No wait time for reading. Just erase & write.