HP 3562A Service Manual page 291

MO D E L 3 562A
RAM G R L/GW
RASLL
RASU L
R F D L
ROW E N
RSTL
STRO B E
SYNC
TCL
W E L
W LOA D L
YA
through
YH
RAM g l obal read (active 10w)Jglobal write. U sed to generate the W E L
s ignal to a l l ow a write transfer i nto memory.
Row ad d ress strobes. C l ock the m u lt i p l exed add ress i nto the dynamic
RAMs.
Ready for data, active l ow. S ignal from d is p l ay to i nform contro l l e r
that previous data po int h a s been p rocessed a n d a new d ata po i nt i s
req u i red.
Row enable. Switches the output of the add ress m u l t i p l exer.
Rest. Software reset for the global RAM board, originates from the
system C P U .
Signal from g lobal t i m i ng c i rc u it used to generate global data strobe
(G DSL).
Output of the d isp lay refresh timer, used to synchronize frame refresh
(approximately 61 Hz).
Term i n ate cou nt, active low . I nd icates that the dis p l ay word count
has gone to zero .
Write enable, active l ow. A l l ows a write transfer i nto memory.
Word load, active l ow. A l l ows the word count from the system C P U
to be loaded i nto the d is p l ay word cou nters.
Memory grant l i nes from the priority decoder to the bus d river.
C I RC U I T D E SCR I PT I O N S
6-71