Abstract
For original paper see ibid., vol.42, no.8, p.1020-4 (1994). T.R.N. Rao et al. (1994) proposed a totally self-checking (TSC) 2-output checker for Berger codes with I=2/sup r-1/ information bits. The article shows that their checker may not be self-testing, as claimed. Hence, the circuit proposed by S.J. Piestrak (2002) is the first correct solution of this design problem.