H838704 Datasheet, PDF (203/402 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family / H8/300H Super Low Power Series

Section 9 Timers
(b) 8-bit mode (TCFL/TCFH)
When CKSH2 is set to 1 in TCRF, TCFH and TCFL operate as two independent 8-bit counters.
The TCFH (TCFL) input clock is selected by bits CKSH2 to CKSH0 (CKSL2 to CKSL0) in
TCRF.
TCFH (TCFL) can be cleared in the event of a compare match by means of CCLRH (CCLRL) in
TCSRF.
When TCFH (TCFL) overflows from H'FF to H'00, OVFH (OVFL) is set to 1 in TCSRF. If
OVIEH (OVIEL) in TCSRF is 1 at this time, IRRTFH (IRRTFL) is set to 1 in IRR2, and if
IENTFH (IENTFL) in IENR2 is 1, an interrupt request is sent to the CPU.
(2) Output Compare Registers FH and FL (OCRFH, OCRFL)
OCRF is a 16-bit read/write register composed of the two registers OCRFH and OCRFL. In
addition to the use of OCRF as a 16-bit register with OCRFH as the upper 8 bits and OCRFL as
the lower 8 bits, OCRFH and OCRFL can also be used as independent 8-bit registers.
OCRFH and OCRFL can be read and written by the CPU, but when they are used in 16-bit mode,
data transfer to and from the CPU is performed via a temporary register (TEMP). For details of
TEMP, see section 9.3.4, CPU Interface. OCRFH and OCRFL are initialized to H'FF upon reset.
(a) 16-bit mode (OCRF)
When CKSH2 is cleared to 0 in TCRF, OCRF operates as a 16-bit register. OCRF contents are
constantly compared with TCF, and when both values match, CMFH is set to 1 in TCSRF. At the
same time, IRRTFH is set to 1 in IRR2. If IENTFH in IENR2 is 1 at this time, an interrupt request
is sent to the CPU.
Toggle output can be provided from the TMOFH pin by means of compare matches, and the
output level can be set (high or low) by means of TOLH in TCRF.
(b) 8-bit mode (OCRFH/OCRFL)
When CKSH2 is set to 1 in TCRF, OCRFH and OCRFL operate as two independent 8-bit
registers. OCRFH contents are compared with TCFH, and OCRFL contents are with TCFL. When
the OCRFH (OCRFL) and TCFH (TCFL) values match, CMFH (CMFL) is set to 1 in TCSRF. At
the same time, IRRTFH (IRRTFL) is set to 1 in IRR2. If IENTFH (IENTFL) in IENR2 is 1 at this
time, an interrupt request is sent to the CPU.
Toggle output can be provided from the TMOFH pin (TMOFL pin) by means of compare
matches, and the output level can be set (high or low) by means of TOLH (TOLL) in TCRF.
Rev. 1.00 Dec. 13, 2007 Page 185 of 380
REJ09B0430-0100