NEC 78K0 Series User Manual page 181

(3) 16-bit timer output control register 0n (TOC0n)
TOC0n is an 8-bit register that controls the TO0n pin output.
TOC0n can be rewritten while only OSPT0n is operating (when TMC0n3 and TMC0n2 = other than 00).
Rewriting the other bits is prohibited during operation.
However, TOC0n4 can be rewritten during timer operation as a means to rewrite CR01n (see 7.5.1 Rewriting
CR01n during TM0n operation).
TOC0n can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation clears TOC0n to 00H.
Caution Be sure to set TOC0n using the following procedure.
<1> Set TOC0n4 and TOC0n1 to 1.
<2> Set only TOE0n to 1.
<3> Set either of LVS0n or LVR0n to 1.
µ
Remark n = 0: PD78F0531, 78F0532, 78F0533
µ
n = 0, 1: PD78F0534, 78F0535, 78F0536, 78F0537, 78F0537D
CHAPTER 7 16-BIT TIMER/EVENT COUNTERS 00 AND 01
Preliminary User's Manual U17260EJ3V1UD
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