Yamaha A-S201 Service Manual page 25

3. FACTORY PRESET
This menu is used to reserve/inhibit initialization of the back-up IC.
3-1. PRESET INHIBIT (Initialization inhibited)
P R S T I N H I
Initialization of the back-up IC is not executed. Select this sub-menu to protect the values set by the user.
3-2. PRESET RESERVED (Initialization reserved)
P R S T R S R V
Initialization of the back-up IC is reserved. (Actual initialization is executed when the power is turned on
next.)
To reset to the original factory settings or to reset the backup IC, select this sub-menu and press the " "
(Power) key to turn off the power.
CAUTION: Before setting to the PRESET RESERVED, write down the existing preset memory content of the tuner. (This
is because setting to the PRESET RESERVED will cause the user memory content to be erased.)
4. AD DATA CHECK
This menu is used to display the A/D conversion value of the microprocessor which detects panel keys and protection
functions by using the sub-menu.
When "4-5. KEY" sub-menu is selected, keys become inoperable due to detection of the values of all keys. However, it
is possible to advance to the next menu by pressing the " " (forward) key or " " (reverse) key on the remote control.
*
Numeric values in the figure are given as reference only.
4-1. PS
Power supply voltage (PS) protection detection.
The voltage at 44 pin (PRPS) of IC203 is displayed.
Normal value: 113 to 175
(Reference voltage: 3.3 V = 255)
* If PS becomes out of the normal value range, the protection function works to turn off the power.
4-2. DC
Power amplifier DC (DC voltage) output is detected.
The voltage at 42 pin (PRD) of IC203 is displayed.
Normal value: 27 to 136
(Reference voltage: 3.3 V = 255)
* If DC becomes out of the normal value range, the protection function works to turn off the power.
P S 1 4 5
D C 0 8 9
A-S201
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