Is a trial court erred by failing to give a defendant separate advisement of his right to counsel and obtaining a waiver of that right?

The trial court erred by failing to give defendant a separate advisement of his right to counsel and obtaining a waiver of that right. The question is whether the error is reversible per se, or whether it is subject to harmless error analysis, either under the standard in Chapman v. California (1967) 386 U.S. 18 (for errors of federal constitutional magnitude) or the standard established under article VI, section 13 of the California Constitution (all other errors). (See People v. Cahill (1993) 5 Cal.4th 478.)