Exception codes - Grid automation - Communication Protocol Manual - REC615 Grid Automation - PCL1 - IEC - ANSI

Table 1. Supported exception codes

Function code	Name	Description
81	Read coil status exception code	Unsuccessful read of discrete outputs status
82	Read digital input status exception code	Unsuccessful read of discrete inputs status
83	Read holding registers exception code	Unsuccessful read of the contents of output registers contents
84	Read input registers exception code	Unsuccessful read of the contents of input registers contents