BBK DV725SI, Руководство по обслуживанию

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3.5.2 function introduction to FLASH
FLASH 16Mbit memorizer, FLASH function pin are shown as follows:
Pin Name Function Voltage (when no disc) Data direction
1-9, 16-25, 48 AO-A19 20 bit address bus I
11 WE Write enable signal, low level is effective 3.23V I
12 RESET Reset, low level is effective 3.23V I
10, 13, 14 NC Blank pin
15 RY/BY Ready/system busy 3.23V O
26 CE Chip enable, low level effective 0V I
27
、
46
VSS Ground
28 OE Output enable signal , low level is effective 0V I
29-3, 6, 38-44 DQ0-DQ14 15 bit data bus O
37 VCC 5V power supply +5V
45 DQ15/A-1
Take word extend mode as data line, and bit extend mode
as address line
I/O
47 BYTE
Select 8-bit or 16-bit output mode. High level is 16-bit
output and low level is 8-bit output
I
3.5.3 function introduction to SDRAM
The function of SDRAM (U211) in the player is to save program taken out by Mt1389 from FLASH and
information of picture and sound taken out from disc when the player is working to form damping, add the
stability of information output and add anti-vibration of the player. The pin function and real voltage are shown
as the following table:
Pin Name Function
Data
direction
Voltage
when
no disc
Pin Name Function
Data
direction
Voltage
when
no disc
1 VDD 3.3V power supply 3.18 28 VSS Ground 0.01
2 DQ0 Data bus I/O 0.94 29 MA4 Address bus I 1.65
3 VDDQ 3.3V power supply I/O 3.19 30 MA5 Address bus I 1.74
4 DQ1 Data bus I/O 0.9 31 MA6 Address bus I 1.49
5 DQ2 Data bus I/O 1.3 32 MA7 Address bus I 1.22
6 VSSQ Ground 0 33 MA8 Address bus I 0.05
7 DQ3 Data bus I/O 1.2 34 MA9 Address bus I 0.04
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