Remote Processing RPC-52 - Manual (Page 34)

SERIAL EEPROM CHAPTER 13
Page 32
DESCRIPTION
The serial EEPROM is a 128 byte, non-volatile device
that stores various RP C-52 pow er up configur ations.
These include baud rate, I/O port, display and keypad
type. 80 bytes are available to the user using the
SPRO M stateme nts.
Information such as calibration constants, recipes, RS-
485 address, or other "soft" inform ation that may change
over time should be stored here.
An EEPROM is more secure than battery backed RAM
because it is more difficult to write to it. Several
microprocessor instructions must take place before a
byte is change d. R AM , on the other h and, requir es only
a momentary pulse to modify its memor y.
Each byte can be written to 100,000 times and r ead from
any number of times. The EEP ROM could be updated
once a day f or over 27 year s before this limit is
exceeded.
Do not constantly store information to the EEPROM.
That is, do not continuously write to it once a second as
part of your program. T his is an electronic part you can
" w e ar o ut " .
PROGRAM EXAMPLE
The following pr ogram example saves and retrieves a
byte of data from the EEPROM.
100 SPROM 0,A
110 A=SPROM(0)