XR82C684CJ-F Datasheet, PDF (68/107 Pages) Exar Corporation – CMOS Quad Channel UART(QUART)

XR82C684
D.7 Explanation of Clock Timing Signals
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Figure 37. Clock Timing
: 3 *   " ( *  ' *  % %7
 tCLK - X1/CLK (External) High or Low Time
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 fCLK - X1/CLK Crystal High or Low Time
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 tCTC - Counter/Timer External Clock High or
Low Time - IP2/IP10 Input
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%% Please note that this limit has no relationship with
the parameter tRTX, which is another spec associated
with the IP2 input.
fCTC - Counter/Timer External Clock Frequency -
IP2/IP10 Input
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 tRTX - RXC and TXC (External) High or Low Time
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