Hitachi H8S/2199 Hardware Manual page 592

REC/PB
VD (except in PB)
Value set in reference
period register 1 (RFD)
Counter
Value set in REF30
counter register (RFC)
Toggle mask
Counter mask
(Clear signal mask)
REF30
REF30P
Figure 26.19 Generation of the Reference Signal when PB is Switched to REC
where RFD Bit is 1 (when VD Signal is Not Detected) (2)
Rev. 1.0, 02/00, page 586 of 1141
PB
Masking
period
Masking
period
25% 25%
REC(ASM)
25%
FDS bit = 1