Set Timing For Overflow Flag (Ovf); Interrupt Sources; Figure 14.9 Set Timing For Ovf Flag; Table 14.2 Interrupt Sources For Duty Measurement Circuit - Renesas H8S/2437 Hardware Manual

14.5.7

Set Timing for Overflow Flag (OVF)

The overflow flag (OVF) in TWCR2 is set to 1 by the overflow signal which is output when
TCNT overflows from H'FF to H'00. Figure 14.9 shows the OVF set timing.
TWCNT
Overflow signal
OVF
14.6

Interrupt Sources

The duty measurement circuit can request two interrupts: TWOVI and TWENDI. Table 14.2 lists
the sources and priorities of these interrupts. Each interrupt can be enabled or disabled by an
interrupt enable bit in TCR or TCSR. Independent signals are sent to the interrupt controller for
each interrupt.

Table 14.2 Interrupt Sources for Duty Measurement Circuit

Interrupt Interrupt Source
TWENDI Duty measurement end
TWOVI TWCNT overflow
Rev. 1.00, 09/03, page 410 of 704
N'FF

Figure 14.9 Set Timing for OVF Flag

N'00
Interrupt Flag Priority
ENDF High
OVF Low