REV.-A
2.3.1.4 ST-RAM (7A) Battery Backup
The ST-RAM (7A) employs a lithium battery (3.00 to 3.35 VDC) for backup, and is used to maintain the initial
data for the printer mechanism and settings for the control panel when the printer power is turned off.
Figure 2-28 shows the ST-RAM (7A) battery backup circuit, and Table 2-21 shows the ST-RAM conditions
when the power is turned on or off.
R58
J
R59.
/
Vss
(7A)
Figure 2-28. Battery Backup Circuit
When the power is turned on under normal conditions, +5 V is applied to
of the ST-RAM, and the CPU
starts read/write operations. When the power is turned off, and the voltage on the +5 V line drops to about
3.3 V or less, transistors
and
turn off, and the voltage from the lithium battery
is applied to
the
terminal of the ST-RAM. In this way, the data in the ST-RAM is maintained.
When the voltage from the lithium battery
the initial data for the printer mechanism and settings for
the control panel are cleared, and default values are set at power is turned on.
Table
ST--RAM Conditions with Power On/Off
Printer Power
+5 V
Line
(Pin 26)
[V]
ST-RAM Mode
OFF
L
L
2.4- 2.7
Data holding
ON
H
H
+ 5
Normal
I
2-33
Содержание LQ-1060
Страница 1: ...EPSON TERMINAL PRINTER L Q 8 6 0 1 0 6 0 TECHNICAL MANUAL ...
Страница 5: ...REVISION TABLE REVISION DATE ISSUED I CHANGE DOCUMENT I I 1st issue I v ...
Страница 68: ...cc o REV A N N n 1 cc b I al cc u co n4 2 1 Figure 2 14 Main Switching 2 21 ...
Страница 79: ...REV A Table 2 20 State of Module 1 1 I W stay E H H L H d O s H H 4 2 32 ...
Страница 203: ...Figure 5 6 MONPS MONPSE Board Voltage Waveforms 5 17 ...
Страница 204: ...REV A Fiaure 5 6 MONPS MONPSE Board Voltage Waveforms z L 5 18 ...
Страница 205: ...Figure 5 6 MONPS MONPSE Board Voltage Waveforms 5 19 ...
Страница 217: ... n 3 m I BUS CONTROL 1 LJ Pc II SYSTEM CONTROL I I L 1 I PERIPHERAL BUS IIF u lJ Figure A 2 PD78213 Block Diagram A 3 ...
Страница 248: ...REV A A 3 DRAWINGS 3 J32 J TI g 4 Figure A 27 MONPS Board Component Layout A 34 ...
Страница 249: ... J30 33r J32 d m b13 G a TI 7 IC20 r El m J24 C2 L cl mow B L U E u Figure A 28 MONPSE Board Component Layout A 35 ...
Страница 250: ... 2 1 1 1 1 I A b 2 Ozaz 1202 C O ZZH Z UOEE vu I 1 Figure A 29 MONPS Board Circuit Diagram ...
Страница 251: ...REV A 1 UXZO xl OX 9 xl Onz b 8M 118 en A N J 93 T 818 Figure A 30 MONPSE Board Circuit Diagram A 37 ...
Страница 252: ...L t g Figure A 31 JUNMM Board Component Layout A 38 ...