Carrier Generator Mode Operation (8-Bit Timer H1 Only) - NEC 78K0/KD1 Series User Manual

8.4.3 Carrier generator mode operation (8-bit timer H1 only)

The carrier clock generated by 8-bit timer H1 is output in the cycle set by 8-bit timer/event counter 51.
In carrier generator mode, the output of the 8-bit timer H1 carrier pulse is controlled by 8-bit timer/event counter 51,
and the carrier pulse is output from the TOH1 output.
In carrier generator mode, the connection between 8-bit timer H1 and 8-bit timer/event counter 51 is as shown
below.
Figure 8-10. Example of Connection Between 8-Bit Timer H1 and 8-Bit Timer/Event Counter 51
INTTM51
(1) Carrier generation
In carrier generator mode, 8-bit timer H compare register 01 (CMP01) generates a low-level width carrier pulse
waveform and 8-bit timer H compare register 11 (CMP11) generates a high-level width carrier pulse waveform.
Rewriting the CMP11 register during 8-bit timer H1 operation is possible but rewriting the CMP01 register is
prohibited.
(2) Carrier output control
Carrier output is controlled by the interrupt request signal (INTTM51) of 8-bit timer/event counter 51 and the
NRZ1 and RMC1 bits of the 8-bit timer H carrier control register (TMCYC1). The relationship between the
outputs is shown below.
CHAPTER 8 8-BIT TIMERS H0 AND H1
8-bit timer/event counter 51
8-bit timer H1
Prescaler CPU
RMC1 Bit NRZ1 Bit
0 0
0 1
1 0
1 1
Preliminary User's Manual U16315EJ1V0UD
TO51
TMMD10,
TMMD11
INTTM51
Selector
INTTM5H1
INTTMH1
TOH1
Output
Low-level output
High-level output
Low-level output
Carrier pulse output
INTC
195