Inconsistent state after step back to the beginning

[Calindro]

When stepping back to the beginning in visualz80r, there seems to be some inconsistency.

I hadn't seen the Reset button before so I stepped back to the beginning via the step back buttons instead. This has led to some kind of inconsistent state where all registers display as 0000 and all checkmarks get ticked. Then, after stepping 2 half-cycles, suddenly all values change at once.

Steps to reproduce:
Reset
Step half-cycle
Step back half-cycle

[floooh]

Hmm, the step-back functionality is implemented by going back to a previous snapshot of the entire node state.

v6502r/src/trace.c

Lines 666 to 675 in bcedbdd

	// load the previous trace item into the simulator and pop it from the trace log
	bool trace_revert_to_previous(void) {
	assert(trace.valid);
	if (trace_num_items() < 1) {
	return false;
	}
	load_item(trace_to_ring_index(1));
	ring_pop();
	return true;
	}

Maybe there's some confusion when the step-back hits the first entry...

I won't have time to work on v6502r stuff anytime soon. But in any case many thanks for the bug report!