8.1.6 Battery and Power Down Reset (Sheet 6/10)
Prime power failure is detected by a voltage comparator that co5V supply with a constant
reference voltage 4.5V provided by transistor voltage source. Capacitor C35 is charged to 4.5V
when power on, and hold a while to be reference level when power down.
Battery BT1 backs up XFC, SRAM and DRAM in the beginning of power down, and BT2 will take
over to back up XFC and SRAM when BT1 discharges to lower level than BT2. DRAM needs more
standby power and higher voltage than XFC and SRAM. Therefore, voice and image stored in
DRAM can be retained for nice hours while the RTC date and user data can keep for three days.
8.1.7 Fax Modem and Audio Circuit (Sheet 7/10)
Modem chip RF144EFXL features an advanced Rockwell proprietary voice compression algorithm.
This algorithm can compress voice to 5.7 kbps with near toll quality playback. DTMF and tone
detection are available during voice codec operation. Echo cancellation techniques are employed
during playback to allow DTMF and tone detection. The pin assignments for 100-pin PQFP are
listed in table 8.1.7-1, and its digital interface characteristics is listed in table 8.1.7-2, analog
interface is listed in table 8.1.7-3.
Table 8.1.7-1 Modem RF144EFXL Pin Functions
Pin
No.
Pin Name
Signal
Name
I/O
Description
Input
Type
Output
Type
1
GP03
Rrelay 1
O
General purpose input/output
IB
OB
2
GP04
Rrelay 2
O
General purpose input/output
IB
OB
3
GP05
Rrelay 3
O
General purpose input/output
IB
OB
4
GP06
General purpose input/output
IB
OB
5
GP07
General purpose input/output
IB
OB
6
OVD2
Connect to digital ground
7
OVD2
Connect to digital ground
8
D7
D7
I/O
Data bus line 7
IA
OB
9
D6
D6
I/O
Data bus line 6
IA
OB
10
D5
D5
I/O
Data bus line 5
IA
OB
11
D4
D4
I/O
Data bus line 4
IA
OB
12
D3
D3
I/O
Data bus line 3
IA
OB
13
D2
D2
I/O
Data bus line 2
IA
OB
14
D1
D1
I/O
Data bus line 1
IA
OB
15
D0
D0
I/O
Data bus line 0
IA
OB
16
OVD2
Connect to digital ground
17
OVA
Connect to analog ov ground
18
RAMPIN
I
Receiver amplifier input
19
NC
No connection
20
NC
No connection
21
OVA
Connect to analogy ov groung
22
+5VD2
Connect to d5V power
Содержание 610
Страница 6: ...CHAPTER 1 GENERAL INFORMATION...
Страница 10: ...Figure 1 4 1 OKIFAX 610 General Appearance Figure 1 4 2 OKIFAX 660 General Appearance...
Страница 11: ...Figure 1 4 3 OKIFAX 610 Operation Panel...
Страница 12: ...Figure 1 4 4 OKIFAX 660 Operation Panel...
Страница 13: ...CHAPTER 2 SPECIFICATION...
Страница 17: ...4...
Страница 22: ...CHAPTER 3 INSTALLATIONS...
Страница 40: ...18 PRT SERVICE SET 60 sec to standby 3 7 30 STANDBY SCROLL DOWN SCROLL UP STOP START 3 7 1 3 7 1 PRINTING 3 7 1...
Страница 41: ...CHAPTER 4 MAINTENANCE...
Страница 45: ...CHAPTER 5 TROUBLESHOOTING...
Страница 77: ...CHAPTER 6 MECHANICAL DISASSEMBLY AND REASSEMBLY...
Страница 93: ...CHAPTER 7 MECHANICAL ASSEMBLY DRAWING AND PARTS LIST...
Страница 95: ...1...
Страница 96: ...2...
Страница 97: ...3...
Страница 98: ...4...
Страница 99: ...5...
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Страница 101: ...7...
Страница 102: ...8...
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Страница 104: ...10...
Страница 105: ...11...
Страница 106: ...12...
Страница 107: ...13...
Страница 108: ...CHAPTER 8 CIRCUIT DESCRIPTION...
Страница 112: ......
Страница 126: ......
Страница 147: ...V CHAPTER 9 FAX CIRCUIT DIAGRAM...