Z86D990 Datasheet, PDF (54/102 Pages) Zilog, Inc. – Low-Voltage Micro controllers with ADC

Z86D990/Z86D991 OTP and Z86L99X ROM
Low-Voltage Microcontrollers with ADC
47
T8 counts down to 0, toggles T8_OUT, sets the time-out status bit (CTR0 D5), and
generates an interrupt if enabled (CTR0 D1). This completes one cycle. T8 then
loads from TC8H or TC8L, according to the T8_OUT level, and repeats the cycle.
The user can modify the values in TC8H or TC8L at any time.The new values take
effect when they are loaded. Do not write these registers at the time the values
are to be loaded into the counter/timer. An initial count of 1 is not allowed. An ini-
tial count of 0 causes TC8 to count from 0 to FFh to FEh. Transition from 0 to FFh
is not a time-out condition (see Figure 34).
PS003807-1002
PRELIMINARY