EEPROM write-read I2C suggestions ... but I am out of cogs

courtens

I need to store 30 words (number values in the range of 0-5000) to the on-board EEPROM. I found this related thread, but there is always a cog required. My problem is, I am out of cogs.

So now I am considering to "import" a I2C object into my main cog, hopping that there will be no naming convention collisions.

Is there a simple stripped down I2C object anyone recommends?

I had a look at pasm_i2c_driver.spin, but I don't know what value to set SCL and devSel to.

PUB WriteWord(SCL, devSel, addrReg, data) 

JonnyMac

I've attached my Spin-only EEPROM and I2C objects -- very simple. Used all the time in commercial apps.

So now I am considering to "import" a I2C object into my main cog, hopping that there will be no naming convention collisions.

Spin's use of dot notation (object.method) means you won't have any naming issues.

courtens

Thank you Jon!

I thought I needed to start a new cog with the object started in it to start use the dot notation naming convention. Is this not so?

Phil Pilgrim (PhiPi)

The dot notation pertains to objects, not cogs. The two are not the same, and you do not need to start a new cog for each object.

-Phil

courtens

Does anyone have a sample file for super-dumb dummies? Somehow I just can't get it to work.

Do I need to call jm.start(device) first? And how, or as what, would do I need to declare "device"?

OBJ                                                                                                      
  jm : "jm_24xx256" 

PUB Go
  jm.wr_word($7000, 1234)

Phil Pilgrim (PhiPi)

Yes, you need to call jm.start(0) first to access the boot EEPROM.

-Phil

courtens

Thank you so much. Thant was just what was needed.

JonnyMac

Here's a tip that may be useful: If you want to preserve a variable between reset/power cycles you can do this:

ee.wr_long(@somevariable, somevariable)

Of course, you have to use the method appropriate for the variable type. By writing into the EEPROM at the location the variable lives in RAM, it will be auto-loaded after the next reset -- no read to call a read method.