Control Of Memory And Head Control Circuit - Sony UP-895 Service Manual

4-4-10. Control of Memory and Head Control Circuit

A system control transfers operation mode data in serial to the memory and head control circuit (IC501).
It then instructs the start and end of the fetch operation (that fetches a video signal to memory) and copy
operation (that feeds the memorized image to the head). The copy operation is carried out when the
COPY key is pressed. The fetch-to-copy operation is carried out when the PRINT key is pressed.
[Fetch mode]
nPRINT_KEY
nREGEN
GADATA
DCLK
nFETCH
nFETCHIN
nFETCHSTOP
[Copy mode]
nCOPY_KEY
nREGEN
GADATA
DCLK
nCOPY
nCOPYING
nCOPYSTOP
4-12
Transfer CLK
Capture start
Transfer CLK
Copy start
Operation mode data
During capture
Capture end
Operation mode data
During copy
Copy end
UP-895/(E)