MS-5024UD/MS-5024UDE Softw Softw Change Change Software Change Change Softw Softw Change 50125 Rev G 11/23/98 ECN 98-486 Change Change Change Change Change procedure outlines the mechanical installation steps required to install a PROM in the MS-5024UD/ circuits circuits integrrrrrated circuits integ integ precautions f precautions f circuits precautions for integ circuits integ precautions f precautions f electricity can destroy integrated circuits (ICs)! To prevent damage to the PROM, a wrist strap and a PLCC IC insertion/extraction tool is highly recommended. The manufacturer cannot be respon- for damage to the PROM as a result of improper handling. Sources Sources Pooooowwwwwer Sources P P Sources Sources P P remove primary and secondary power before working on the system! Disconnect battery backup power before working on the system! Proceed by disconnecting AC power to the panel at the main service circuit breaker (not circuit breaker on the fire control panel’s power supply). Wait 60 seconds to allow for capacitive discharge before touching any of the system’s Reverse the procedure for powering up the system – AC first, then batteries. Circuit Pin Con Circuit Pin Con Circuit Pin Con Circuit Pin Convvvvversionersionersionersionersion Circuit Pin Con proper orientation of any IC removed or installed! Note location of Pin 1 with respect to the corner and dot on the body of the IC and the relationship to the flattened corner on the IC socket. replacement PROM must be installed in the same manner as the PROM removed. Failure to observe orientation will result in destruction of the PROM. Pin 1 Pin 1 Pin 1 Pin 1 Pin 1 Cor Cor Cornernernernerner Cor Cor Pin 1 Pin 1 Pin 1 Pin 1 Pin 1 Cor Cor Cornernernernerner Cor Cor Replacement Replacement Replacement Replacement Replacement proper orientation of any IC removed or installed! To replace the PROM, complete the following steps: Remove all power (AC and battery) before proceeding with PROM replacement. If necessary, disconnect any installed option modules which may inhibit access to PROM. Locate U23 (center right of the board). Gently loosen and remove the PROM from U23. Install the replacement PROM in location U23. Observe proper orientation! The dot on the IC be positioned to the left and the flattened corner of the IC should align with the flattened of the socket. Use care to insure that the PROM’s pins are not bent or broken during Reconnect any option modules which were removed in Step 2. Reconnect power (AC and batteries). (U23) (U23) (U23) (U23) (U23) and TTTTTestingestingestingestingesting and and and and and test the MS-5024UD/MS-5024UDE after PROM replacement. of 3 50125 Rev G ECN 98-486 11/23/98 Softw Softw Changes Changes Software Changes Changes Softw Softw Changes following Table summarizes the MS-5024UD software changes, specifying these changes by Number and Release Number.