80C196KB USER’S GUIDE
15.3 Bus Width
The 80C196KB external bus width can be run-time
conFigured to operate as a 16 bit multiplexed address/
data bus, or as an MCS-51 style multiplexed 16 bit ad-
dress/8 bit data bus.
During 16 bit bus cycles, Ports 3 and 4 contain the
address multiplexed with data using ALE to latch the
address. In 8-bit bus cycles, Port 3 is multiplexed with
address/data but Port 4 only outputs the upper 8 ad-
dress bits. The Addresses on Port 4 are valid through-
out the entire bus cycle. Figure 15-9 shows the two bus
width options.
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16-Bit Bus Cycle
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8-Bit Bus Cycle
Figure 15-8. Address Valid with Write Strobe Mode
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(a) 16-Bit Bus
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(b) 8-Bit Bus
Figure 15-9. Bus Width Options
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数控原理与维修
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Содержание 80C196KB Series
Страница 1: ...November 1990 80C196KB User s Guide Order Number 270651 003 http www agreenleaf cn...
Страница 59: ...80C196KB USER S GUIDE Figure 11 7 Ideal A D Characteristic 270651 37 55 http www agreenleaf cn...
Страница 60: ...80C196KB USER S GUIDE Figure 11 8 Actual and Ideal Characteristics 270651 38 56 http www agreenleaf cn...
Страница 61: ...80C196KB USER S GUIDE Figure 11 9 Terminal Based Characteristic 270651 39 57 http www agreenleaf cn...
Страница 70: ...80C196KB USER S GUIDE Figure 13 5 Reset Sequence 80C196KB Reset Sequence 270651 45 66 http www agreenleaf cn...
Страница 83: ...80C196KB USER S GUIDE 270651 80 Figure 15 14 AC Timing Diagrams 79 http www agreenleaf cn...
Страница 84: ...80C196KB USER S GUIDE 270651 81 270651 84 Figure 15 14 AC Timing Diagrams Continued 80 http www agreenleaf cn...