Hardware Manual for the PCD3 Series│Document 26/789; Version E 5│31.01.2005
Saia-Burgess
Controls Ltd.
Backup of the user program
PCD3.Mxxx0 Classic CPUs and expansion housings
3-20
3
3.13
Backup of the user program
3.13.1 General
PCD3.Mxxx0
onboard flash
M3020
M3230
M3330
M5440
M5540
Memory
128
kBytes
256
kBytes
512
kBytes
Backup onboard flash
128
kBytes
256
kBytes
256
kBytes
onboard
or
512
kByte
flash card
PCD7.R500
The PCD3.M5xx0 is equipped with 512 kBytes of RAM as standard and can be fitted
with an optional PCD7.R500 flash card. The flash card makes it possible to save
a failsafe copy of the application after downloading (code, text/DBs and extension
memory).
We recommend fitting all PCD3.M5xx0 units with the flash card, to avoid any
accidental loss of data.
Even with backup to the flash card, the source files for the project must be retained,
as the application is only stored in the PCD as machine code.
It is also possible to use the flash card to transfer applications from one controller to
another, and to create a backup of RAM texts and DBs in extension memory (address
≥ 4000) while the controller is in operation.
If it transpires when the PCD3 is started up that one of the RAM memories has been
corrupted (e.g. after a power failure with a flat or missing battery), the application is
automatically copied to the PCD. With test 400H this can be controlled.
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