Oki Dr.63514, User Manual, Page: 54 / 101

Chapter 2. Functions
2-33
2.7 Probe Cable
The emulator’s probe cable carries the following six signals.
•
Break (EXT.BRK) input
•
Sync out (SYNC.OUT) output
•
Trace (PROBE0 to PROBE3) inputs
2.7.1 Break Signal Input
If external breaks are enabled, a rising edge in this signal produces a break request.
EXT.BRK
(Probe cable)
51K Ω
+
-
1/2 VDD
Rising edge
detection
circuit
External
break request
Figure 2-11 Break Signal Input
A built-in voltage conversion circuit converts the break (EXT.BRK) input level of VDD, the port interface
power supply voltage (0.9 to 5.5 V), to the internal “H” level.
The break request coincides with the beginning of an instruction S2 cycle.
M1 M1 M2 M1
S1 S2 S1 S2 S1 S2 S1 S2 S1
M1
External break occurs
System clock
M1S00
EXT.BRK
External
break request
Figure 2-12 External Break Input Timing