> At 12:24 1/12/99 -0000, you wrote:
        > >Is the 12c508 available as an electrically erasable device?

        > No, You can check the forth quarter product guide from the
        > microchip web site for a run down on the available PICs.

        The folowing table is taken from the pic 12c5xx datasheat
(http://www.microchip.com/Download/Lit/PICmicro/12C5XX/40139e.pdf)

        Device          Memory
                EPROM Program   ROM Program     RAM Data        EEPROM Data
        PIC12C508       512 x 12                                25
        PIC12C508A      512 x 12                                25
        PIC12C509       1024 x 12                               41
        PIC12C509A      1024 x 12                               41
        PIC12CE518      512 x 12                                25      16
        PIC12CE519      1024 x 12                               41      16
                        PIC12CR509A             1024 x 12               41

What is the difference between EPROM and ROM Program Memory in the 12C50X
Chips?

Why am I having the feeling that I am asking a really stupid question?

Michael

The ROM types (CR) are Mask ROM devices that are essentially programmed at manufacture.  The EPROM types (CE) have standard EPROM memory, but the standard devices have no window, effectively making them OTP devices.

Regards

Mike Rigby-Jones