Description
📌 FANUC A20B-2902-0412 — 4 MB FROM Module with 256 KB SRAM
Description:
The FANUC A20B-2902-0412 is a combined memory module used in FANUC CNC control electronics. It contains both Flash ROM (FROM) storage and static RAM (SRAM), acting as a system memory board that holds the controller’s firmware, programs, parameters, and working data required during operation.
Key Features:
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💾 Flash ROM: Approximately 4 MB of non-volatile memory to store the CNC controller’s operating software/firmware and related system code.
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🧠 SRAM: 256 KB static RAM used as working memory for runtime variables, buffer storage, and active data handling.
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🛠️ Part Family: Member of the A20B-2902 series of control PCBs in FANUC CNC systems — typically in Series 16/18/21 controls and similar architectures where this combined memory configuration is specified.
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🧾 Note: After replacing or installing this module in a CNC controller, all programs, parameters, and FROM files must be reloaded from backup because SRAM contents are volatile and the Flash portion may not contain the specific data needed for that machine.