Yamaha SP2060, Service Manual

Page: 39 / 123

SP2060
39
3. Outline of Tests
3-1. SRAM Test (NO. 01)
Content: Checks Address Bus and Data Bus of SRAM.
Example of execution screen
*** 01. SRAM ***
SRAM AddressBus OK!
SRAM DataBus OK!
EXIT:[ENTER]
Displayed at OK



*** 01. SRAM ***
SRAM AddressBus NG!
SRAM DataBus NG!
EXIT:[ENTER]
Displayed at NG



Messages:
• When address bus access abnormality is detected: NG: SRAM AddressBus NG!
• When data bus access abnormality is detected: NG: SRAM DataBus NG!
Troubleshooting:
The SRAM (CPU circuit board: IC009) may be defective.
Or check the connection between SRAM and CPU (CPU circuit board: IC002).
Notes:
When SRAM test is executed, the data stored in the SRAM will be cleared.
After SRAM test is executed, initialize the SRAM (CURRENT BACKUP or FACTORY SETUP). (Refer to 68 page.)
3-2. BATTERY Test (NO. 02)
Content: Measures and checks the backup battery voltage with A/D automatically.
Also the measured battery voltage is displayed.
Example of execution screen
*** 02. BATTERY ***
VOLTAGE:3.05[V]
OK.
VOLTAGE:2.50[V]
NG:BATTERY LOWER ERROR!
EXIT:[ENTER]
Displayed at OK



Displayed at NG



Messages:
• At battery over voltage: NG: BATTERY OVER ERROR!
• At lower battery voltage: NG: BATTERY LOWER ERROR!
• At shortage of battery voltage: NG: BATTERY EMPTY ERROR!
Troubleshooting:
Check the backup battery (CPU circuit board: BT001).
Or check the route from the backup battery to PTK[1] (114pin) and AN[6] (238pin) of CPU (CPU circuit board: IC002).
Applicable Range of Measured Voltage:
• Acceptable voltage range : 2.80 [V] -3.50 [V]
• Over voltage : 3.51 [V] or above
• Low voltage : 2.79 [V] -0.51 [V]
• Voltage shortage : 0.5 [V] or below