Software Version Check; About Replace The Microprocessor With A New One - Marantz SR4021 Service Manual

2. SOFTWARE VERSION CHECK

A version of microprocessor is confirmed by the following.
1. Press the POWER ON/STANDBY button to turn on the unit.
2. Press MUTE and the SOURCEDIRECT buttons more than 3 seconds, while pressing the SLEEP button.
3. The front display shows "yymmdd-x" of software version for 4 seconds, while press those buttons.
REMARK : yy is two digits of year. mm is month. dd is date. x is version of release date.
INDICATION EXAMPLE : 060419-1

3. ABOUT REPLACE THE MICROPROCESSOR WITH A NEW ONE

When replaced of the U-PRO (Microprocessor) or the Flash ROM, confirm contents of the following.
PWB Pos.
Name No.
FRONT IC91 TMP87PM78FG, SR4021
After replaced
A : Mask ROM (With software). No need write-in of software to the microprocessor.
B : Flash ROM (With software). Usually, no need write-in of software. But, when the software was updated, you should be
write-in of the new software to the microprocessor or flash ROM. Please check the software version.
C : Empty Flash ROM (Without software). You should be write-in of the software to the microprocessor or flash ROM.
Refer to "Update procedure" or "writing procedure", when you should be write-in the software.
Description
2
After
Remark
replaced
A OTP