Brother HL-1660e Series User Manual page 35

3) The attached Printer SIMM map shows the memory map for 4 SIMMs combined.
(6) ROM block
ROMs store the CPU control program and font data. ROMs are two 32Mbit masked ROMs.
Optional sockets are available for two 8Mbit EPROM (µPD27C8000DZ-120 - NEC or equivalent)
for expansion.
ROM access time should be less than 120nsec.
(7) DRAM block
DRAMs are used for receiving buffer or working area of the CPU. The DRAM block contains four
16Mbit DRAMs, thus having 8MB memory capacity in total.
The refreshing method is CBR (Cas Before Ras).
DRAM access time should be less than 80nsec.
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