April 2011
Intermediate to advanced
312 pages
9h 32m
English
Content preview from Interfacing PIC Microcontrollers
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Interfacing PIC Microcontrollers
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chip has three inputs CBA, which receive a binary select code from the proces-
sor. The corresponding output is taken low ⫺ for example, if binary 6 is input
(110), output Y6 is selected (low), while all the others stay high. This decoder
can generate 8-chip select signals, and if attached to the high address lines of
a processor, enable the memory chips in different ranges of addresses. In our
system here, only the least significant input (A) and two outputs (Y0, Y1) are
used, giving a minimal system. The additional address decoder outputs could
be used to control extra memory chips attached to the same set of address ...