HD64F3437TF16 Datasheet, PDF (669/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

FRC (H and L)—Free-Running Counter
H'92, H'93
FRT
Bit
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Initial value 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Count value
OCRA (H and L)—Output Compare Register A
H'94, H'95
FRT
Bit
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Initial value 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Continually compared with FRC → OCFA is set when OCRA = FRC.
OCRB (H and L)—Output Compare Register B
H'94, H'95
FRT
Bit
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Initial value 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
Continually compared with FRC → OCFB is set when OCRB = FRC.
640