Signal Descriptions; Abort(Abt)/Reset (Rst) Switch (S1); Figure 6-3. Mx Signal Timings - Motorola MCPN750A Installation And Use Manual

Time Slot 15
MMXCLK
MMXSYNC#
Reserved
MMXDO
DCD2
MMXDI

Signal Descriptions

Serial Ports Defined:
CTSn - clear to send
DCDn - data carrier detected
DSRn - data set ready
DTRn - data terminal ready
RIn - ring indicator
RTSn - request to send
ABORT (ABT)/RESET (RST) Switch (S1)
The MCPN750A SBC contains a single push button switch that provides
both ABORT and RESET functions. When the switch is depressed for less
than 3 seconds, an interrupt is generated to the processor via ISA interrupts
IRQ8. If the switch is held for more than 3 seconds, a board hard reset is
generated.
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Time Slot 0 Time Slot 1
RTS3
CTS3

Figure 6-3. MX Signal Timings

Time Slot 2
DTR3 RTS1
DSR3 DCD3
Block Diagram
Time Slot 3
RTS2
CTS1
6
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