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Chapter 19
Meter Controller / Driver
User’s Manual U16504EE1V1UD00
(1)
Free running up counter (SMCNT)
MCNT is an 8-bit free running counter. It is also a register that executes an increment at the rising
edge of the input clock.
A PWM pulse with a resolution of 8 bits can be created. The duty factor can be set in a range
of 0 to 100%.
The count value is cleared in the following cases.
When RESET signal input
When counter stops (PCE = 0)
(2)
Compare register n0 (MCMPn0)
MCMPn0 is an 8-bit register that can rewrite a complete value according to the specification
by bit 4 (TENn) of the compare control register n (MCMPCn).
The values of these registers are cleared to 00H at RESET. The hardware is cleared to 0 by
RESET.
MCMPn0 is a register that supports read/write only for 8-bit access instructions.
MCMPn0 continuously compares its value with the SMCNT value. When the two values match, a
match signal on the sin side of the meter n is generated.
(3)
Compare register n1 (MCMPn1)
MCMPn1 is an 8-bit register that can rewrite compare values through specification of bit 4 (TENn)
of Compare control register n (MCMPCn).
RESET input sets this register to 00H and clears hardware to 0. MCMPn1 is a register that sup-
ports read/write only for 8-bit access instructions. MCMPn1 compares its value with the SMCNT
value. When the two values match, a match signal on cos side of the meter n is generated.
(4)
1-bit addition circuit
The 1-bit addition circuit repeats 1-bit addition/non-addition to the PWM output alternately upon
MCNT overflow, and enables the state of the PWM output between the current compare value and
the next compare value. This circuit is controlled by bits 2 and 3 (ADBn0, ADBn1) of the MCMPCn
register.