OKIDATA OF1050, Service Manual

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Service Guide OF1050/2350/2450
Chapter 3 Board Description/Printer Operation
3.12 MEMO (memory) Circuit Diagram (option)
The optional memory board (MEM/MEM-2/MEM-3), is used for expanding the OKIFAX unit's Image
(picture) memory..
Block diagram
Figure 3.12.1 shows a related signal of memory board.
MEMO/MEMO-2/MEMO-3 circuit consists of the following block.
1. 512 kbyte pesudo static RAM x 4 (RAM1 to RAM4). Used as follows: Picture memory for the ECM
send/receive modes. Picture memory for the memory transmission mode. Picture memory for the
retransmission data. Picture memory for the reception in memory
2. Memory capacity
One of 512 kbyte (MEMO) or 1 Mbyte (MEMO-2) memory board can be added for OKIFAX 1050.
One of 512 kbyte (MEMO), 1 Mbyte (MEMO-2) or 2 Mbyte (MEMO-3) memory board can be added for
OKIFAX 2350/2450.
The relationship between memory capacity and mounted boards are shown in the following table:
Equipment Memory
Capacity RAM1 RAM2 RAM3 RAM4 Mounted
Board
Name
Okifax
1050 OKIFAX Mounted Not
mounted Not
mounted Not
mounted MEMO
1 Mbyte Mounted Mounted Not
mounted Not
mounted MEMO-2
Okifax
2350/2450 512 kbyte Mounted Not
mounted Not
mounted Not
mounted MEMO
1 Mbyte Mounted Mounted Not
mounted Not
mounted MEMO-2
2 Mbyte Mounted Mounted Mounted Mounted MEMO-3
Note: Back-up time on electrical interruption; Min. one hour for OKIFAX 2450. The OKIFAX 1050/2350
does not back-up messages received in memory when power is lost.
3. Image memory capacity