Yamaha RX-V1800 Service Manual page 29

5. Press the [RDY] button. (Fig. 12)
The writing ready state will be set.
Select the port of RS-232C to use and press the [connect] button
6. Press the "MASTER ON/OFF" key of the main
unit to turn it on. (Fig. 13)
7. While pressing the "A/B/C/D/E" key of the main
unit, connect the power cable of the main unit to
the AC outlet. (Fig. 13)
At this time, press and hold "A/B/C/D/E" key for
3 seconds or longer.
"MASTER ON / OFF" key
Press [open] button to open the window
Select "Vx800a_data1_verxxxxx.hex"
Fig. 12
"A/B/C/D/E" key
Fig. 13
RX-V1800/HTR-6190/DSP-AX1800
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