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FANUC Alarm WNDW-020 — WARN Bad buffer length on read

FANUC WNDW-020 (“WARN Bad buffer length on read”): The buffer_size parameter in a INI_DYN_DISI INI_DYN_DISR, INI_DYN_DISS or READ_KB call is invalid First check: Specify a value in the range 10-128 for INI_DYN_DISx calls; for READ_KB calls, specify a range of 1-128, unless the accept mask is zero, when a buffer_size value of zero is permitted.

Updated 2026-09-17 · LogrobotLM reference

Description

The buffer_size parameter in a INI_DYN_DISI INI_DYN_DISR, INI_DYN_DISS or READ_KB call is invalid

Remedy

Specify a value in the range 10-128 for INI_DYN_DISx calls; for READ_KB calls, specify a range of 1-128, unless the accept mask is zero, when a buffer_size value of zero is permitted.

Related codes

WNDW-018WARN Invalid file name stringWNDW-019WARN Write to file w/o windowWNDW-021WARN Invalid timeout valueWNDW-022WARN Zero term char mask in read

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