Time Constant Register A (Tcora); Time Constant Register B (Tcorb); Timer Control Register (Tcr) - Hitachi H8S/2378, H8S/2378R Series Hardware Manual

13.3.2

Time Constant Register A (TCORA)

TCORA is 8-bit readable/writable register. TCORA_0 and TCORA_1 comprise a single 16-bit
register so they can be accessed together by a word transfer instruction.
The value in TCORA is continually compared with the value in TCNT. When a match is detected,
the corresponding CMFA flag in TCSR is set to 1. Note, however, that comparison is disabled
during the T2 state of a TCORA write cycle.
The timer output from the TMO pin can be freely controlled by this compare match signal
(compare match A) and the settings of bits OS1 and OS0 in TCSR.
TCORA is initialized to H'FF.
13.3.3

Time Constant Register B (TCORB)

TCORB is 8-bit readable/writable register. TCORB_0 and TCORB_1 comprise a single 16-bit
register so they can be accessed together by a word transfer instruction.
TCORB is continually compared with the value in TCNT. When a match is detected, the
corresponding CMFB flag in TCSR is set to 1. Note, however, that comparison is disabled during
the T2 state of a TCOBR write cycle.
The timer output from the TMO pin can be freely controlled by this compare match signal
(compare match B) and the settings of bits OS3 and OS2 in TCSR.
TCORB is initialized to H'FF.
13.3.4

Timer Control Register (TCR)

TCR selects the clock source and the time at which TCNT is cleared, and controls interrupts.
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