eZ80L92 MCU
Product Specification
82
Table 31. PRT Timer Out Operation Example (Continued)
Parameter
Control Register(s)
TMRx_CTL[3:2]
TMRx_CTL[4]
Value
00b
PRT Clock Divider = 4
CONTINUOUS Mode
PRT Reload Value
1
{TMRx_RR_H,
TMRx_RR_L}
0003h
Programmable Reload Timer Registers
Each programmable reload timer is controlled using five 8-bit registers. These registers
are the Timer Control register, Timer Reload Low Byte register, Timer Reload High Byte
register, Timer Data Low Byte register, and Timer Data High Byte register.
The Timer Control register can be read or written to. The timer reload registers are Write-
Only and are located at the same I/O address as the timer data registers, which are Read-
Only.
Timer Control Registers
The Timer Control register, described in Table 32, is used to control operation of the timer,
including enabling the timer, selecting the clock divider, enabling the interrupt, selecting
between CONTINUOUS and SINGLE PASS modes, and enabling the auto-reload feature.
Table 32. Timer Control Registers (TMR0_CTL = 0080h, TMR1_CTL = 0083h,
TMR2_CTL = 0086h, TMR3_CTL = 0089h, TMR4_CTL = 008Ch, or TMR5_CTL
= 008Fh)
Bit
7
0
6
0
5
0
4
0
3
0
2
0
1
0
0
0
Reset
CPU Access
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Note: R = Read only; R/W = Read/Write.
Bit
Position
Value Description
7
0
The timer does not reach its end-of-count value. This bit is reset
to 0 every time the TMRx_CTL register is read.
PRT_IRQ
1
The timer reaches its end-of-count value. If IRQ_EN is set to 1,
an interrupt signal is sent to the CPU. This bit remains 1 until the
TMRx_CTL register is read.
PS013015-0316
Programmable Reload Timers
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