On Wed, 11 Mar 1998 15:01:41 +1300 Gavin Jackson writes: >I have two questions concerning the 12C508 PIC's. >The first is the version it comes in. I had a look >at the data sheet and under 'General Description' >it says: ' The PIC 12C5XX are available in the cost- >effective One-Time-Programmable (OTP) versions >which are suitable for production in any volume.' Both versions are the same chip. The OTP version is an EPROM, but it is in a cheap black plastic package so it is impossible to shine UV light on the chip to erase it. The more expensive "JW" version is in a cermic package with a window so it is possible to erase it. The JW chips are typically used for development, when the program is finalized it is then programmed into a OTP version for shipment. Again, both versions are exactly the same chip. They are programmed with the same hardware and software. The only difference is that the OTP one can't be erased because of the package. This is compared to a Mask ROM chip used by other manufacturers, where the program is actually printed on the chip as it is made. In this case, you have to submit the program to the factory, order a fairly large number of chips, and wait a few weeks for them to be made. Thus it is not possible to "easily customize" the program compared to taking a blank OTP off of your shelf and putting a custom program in it. _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]