Question

How is the processor enter into a BDM state?

(a) BDM signal

(b) Start signal

(c) BDM acknowledge signal

(d) Start signal of the processor

The question was posed to me by my school principal while I was bunking the class.

This interesting question is from Debugging Technique:Xray topic in chapter Emulation and Debugging Techniques of Embedded Systems

Answer 1

Right option is (a) BDM signal

Easy explanation: The assertion of the BDM signal or by executing the special BDM instruction, the processor enter into the BDM state and when the processor enters into the BDM mode, low-level microcode takes the processor which allows the breakpoint to be set, registers to be accessed and so on.