Saia-Burgess Controls AG
Hardware manual for PCD3 series │ Document 26-789 ENG19│ 2018-06-29
Storage space on the PCD3
PCD3.Mxxx0 Classic CPU and expansion enclosure
3-48
3
3.18.2
Memory management (PCD3 without integrated μSD flash card)
In the case of automation devices with
no integrated μSD card and which are
equipped with the COSinus system, the
user application is copied directly to the
user memory from Saia PG5
®
. If no valid
program is detected in the user program
when the controller is started up, a search
is executed for a backup program in the
onboard flash or an optional memory
module.
PCD3.Mxx4x
PCD3.M3xxx
PCD3.M2x30
PCD7.R562
Loading of the user program from PG5® onto Saia PCD®
automation devices and allocation of different data between
the storage media.
On-Board Flash
save
if required
RAM TEXT/DB
SRAM
User program
ROM TEXT/DB
Media (R, T, F)
File system
Flash memory modules
PCD3.M3xxx, PCD3.M554x, PCD3.M2130, PCD3.M2330
PCD7.R5xx
PCD7.R6xx
PCD7.R-SD
PCD7.R5xx
PCD7.R6xx
PCD7.R-MSD
RAM TEXT/DB
SRAM
User program
ROM TEXT/DB
Media (R, T, F)
File system
RAM
Memory = User Program Memory (RAM)
In these systems, the User Program Memory consists of a RAM (Random Access
Memory) and includes the program code and a range of text and DB memory
(addresses 0…3999). Furthermore, it contains the extension memory, which also
contains texts and DBs (addresses
≥
4000) as well as the media R, T, F.
All texts and DBs are always in RAM on this PCD3. The main difference between
the texts and DBs in the text/DB memory segment and those in the extension
memory is the higher maximum capacity of the DBs and texts.