Fostex CR200 Service Manual page 53

(8) Timing Chart
Timing chart when powering on
1
POWER (IN)
XRST (IN)
XPFAIL (IN)
RAME
XSVRST
MACK (IN)
XTAL OFF
1) Turn on the power.
2) XRST goes ÒHÓ and reset is turned off.
3) After reset is turned off, the unit stands by till XPFAIL goes ÒHÓ.
4) After XPFAIL goes ÒHÓ, the microprocessor starts operating. RAME goes ÒHÓ and the external RAM is put into ÒenableÓ condition.
5) XSVRST goes ÒHÓ and the servo circuit starts operating.
2 Timing chart when in blackout.
POWER (IN)
XRST (IN)
XPFAIL (IN)
XSVRST
RAME
1) If power supply voltage drops and at a certain level, XPFAIL goes ÒLÓ.
2) When XPFAIL is at ÒLÓ, the unit is in internal interruption mode and the Current Operation mode and disc data wiill be backed up.
3) At the same time, XSVRST goes ÒLÓ and the servo circuit will be reset. RAME goes ÒLÓ and the external SRAM will be disabled.
4) XRST also goes ÒLÓ and is reset.
CAUTION : If XRST goes ÒLÓbefore RAME goes ÒLÓ, value of backup RAM (IC352) will not be memorized correctly.
1)
2)
3)
4)
About 100us
About 5ms
5)
CR200
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