EZ80L92MCU Datasheet, PDF (95/241 Pages) Zilog, Inc. – eZ80Acclaim Flash Microcontrollers

eZ80L92 MCU
Product Specification
80
the PRT counter being updated on the fifth rising edge of the system clock after the rising
edge occurs at the port pin.
Timer Output
Two of the Programmable Reload Timers (Timers 4 and 5) can be directed to GPIO Port B
output pins (PB4 and PB5, respectively). To enable the Timer Out feature, the GPIO port
pin must be configured for alternate functions. After reset, the Timer Output feature is dis-
abled by default. The GPIO output pin toggles each time the PRT reaches its end-of-count
value. In CONTINUOUS mode operation, the disabling of the Timer Output feature
results in a Timer Output signal period that is twice the PRT time-out period. Examples of
the Timer Output operation are illustrated in Figure 21 and Table 31. In these examples,
the GPIO output is assumed to be Low (0) when the Timer Output function is enabled.
CLK
PRT Clock
(Clock ÷ 4)
IOWRN
PRT Count
Value
Timer
Output
I/O Write to TMRx_CTL Enables PRT
X
3
2
1
3
2
Figure 21. PRT Timer Output Operation Example
Table 31. PRT Timer Out Operation Example
Parameter
PRT Enabled
Reload and Restart Enabled
PRT Clock Divider = 4
CONTINUOUS Mode
PRT Reload Value
Control Register(s)
TMRx_CTL[0]
TMRx_CTL[1]
TMRx_CTL[3:2]
TMRx_CTL[4]
{TMRx_RR_H, TMRx_RR_L}
1
Value
1
1
00b
1
0003h
PS013012-1004
PRELIMINARY
Programmable Reload Timers