Sony VPL-VW12HT Service Manual page 51

The memory structure of the VW12HT is based on earlier
models in the VPL-X600 series, with part of the structure
following the memory structure adapted to the home theater
VPH-D50HT series.
The memory devices are distributed into three areas as
shown in the table above.
Each memory device contains only one kind of memory,
which is divided into 6 blocks as shown below, but some
memory blocks (Staus, Chroma, WB) contain different
amounts of memory.
• SET memory
• CH memory
• STATUS memory
• CHROMA memory
• W/B memory
• VIDEO memory
A simple explanation of the data flow is as follows.
When the power plug is first plugged in when the set is in the
Factory Standby state, all the data in the internal ROM is
copied into the external NVM memory (non-volatile
memory: EEPROM).
When Power ON occurs, the memory data required by the
current input signals and set state is selected from the above
mentioned blocks and expanded into internal RAM.
When selection settings and adjustments are performed
here, those settings and adjustment data items that are
effective in User mode or effective in Service/Factory mode
(W/B, Device Adjust) automatically trigger memory
operation (when "Save To Memory" is selected on the Menu
screen) so that they are written into and stored in non-
volatile memory.
In User mode, Reset is an effective adjustment item. When
Reset is performed the system returns to the initialization
values in internal ROM. These are the valuesset when the set
is shipped from the factory.
In Service/Factory mode, Reset is not effective and as
adjustment of various items and memory operations are
stored at this time in the NVM memory, care must be taken
not to lose either the factory adjustment data provided when
the set was shipped from the factory, or any previously
saved data.
VPL-VW12HT
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