[Power Hungry]

Originally Posted by JackandJanet

One thing I DO know, Northern, is that a weak or dead battery will not destroy your tunes, either what's loaded in the PCM or in the programmable memory of the Gryphon.

Consider: you can take the Gryphon out of the vehicle for extended periods (which is equivalent to having no battery) and, you can take the battery out of the truck with the same results (although the PCM has to relearn its idle strategy and maybe a couple of other things I think after an extended period with no "keep alive" power).

The technology in both the Gryphon and the PCM is similar (maybe the same) as what you see in USB "thumb drives". Now, if you were to zap any of these with high voltage, all bets are off.

- Jack

I wouldn't use it as a wheel chock either!

You are correct, Jack. Both the PCM and the Gryphon (as well as pretty much any other programmer on the market) use what is call "Flash" memory. This is the same stuff you find in thumb drives, digital cameras, and about a zillion other things.

Here's a quick rundown of Flash Memory:

Flash memory is really cool because it is BIG on storage, has a very small footprint (a 8GB Micro-SD is about the size of your pinkie nail), and is CHEAP to produce. It is non-volatile which means that unlike RAM (high speed memory used in most PCs), it doesn't need power to store the data. The data gets "burned" onto the storage grid. When you need to make a change, you can then "Flash" it to erase it and re-write it. It also has a LONG retention rate (on the order of years).

The drawbacks are it is SLOW (compare to RAM, anyway) and you can't erase and re-write 1 byte at a time. You have to erase the memory in blocks (4K, 8K, 64K, etc) which means you have to be able to copy a whole block of data elsewhere, erase the block, and write it back with the change included. Having to read and write 65,536 bytes to make 1 change is not fast. This is why 1 GB of RAM is roughly 50 times the size (footprint) of 1GB of Flash.

So as I said, most (if not all) programmers as well as all re-flashable use Flash Memory because of the reliability of the data retention. Remove the unit? No problem. Batter is dead? No problem.

I will mention that because of the way the data is written in Flash memory, this is why we DO NOT RECOMMEND programming in cold weather. If the flash temp is below spec, the data may not write correctly resulting in data errors.

See? Learned something new today!