Mitsubishi Electric Q26UD(E)HCPU User Manual page 32

(7) Connection of up to 7 extension base units
Up to seven extension base units can be connected to the Q series CPU module.
The overall extension cable length is 13.2m, which allows flexible layout of base units.
(8) Memory extension
By extending the memory capacity of a CPU module, large size files can be managed. Comments can be set to
all data devices and old programs can be saved as correction history.
(a) Memory card
A memory card (maximum 32M bytes) can be installed. (The maximum size is available only for ATA cards.)
Memory cards are used for the following operations.
• Boot operation
• Restoring backup data
• Writing programs to the ROM
Data that cannot be stored in the built-in memory of the CPU module, such as sampling trace data and file
register data, can be stored as well.
(b) SD memory card
SD memory cards are used for the following operations.
• Boot operation
• Restoring backup data
• Data backup
• Data logging
(c) Extended SRAM cassette
An extended SRAM cassette extends the capacity of the standard RAM in a CPU module.
• An extended SRAM cassette can be used together with an SD memory card, allowing users to store data
separately (for example, boot data in an SD memory card and device data in an extended SRAM
cassette). This improves maintainability.
• With existing CPU modules, file register areas in the standard RAM and an SRAM card cannot be
accessed sequentially, and the boundary needs to be considered at programming. If the standard RAM
capacity is extended using an extended SRAM cassette, the device area can be extended without
considering the boundary.
Remark
Memory extension methods differ depending on the CPU module. (
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Page 35, Section 2.2)