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Timer/counter mode control register (tmod), Timer/counter control register (tcon) – Maxim Integrated 71M6513H Power Meter IC Family Software User Manual

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71M651x Software User’s Guide

Timer/Counter Mode Control Register (TMOD)

MSB

LSB

GATE

C/T

M1

M0

GATE

C/T

M1

M0

Timer 1

Timer 0

Table 6-20: The TMOD Register

Bit

Symbol

Function

TMOD.7
TMOD.3

Gate

If set, enables external gate control (pin int0 or int1 for Counter 0 or 1,
respectively). When int0 or int1 is high, and trx bit is set (see TCON register), a
counter is incremented every falling edge on t0 or t1 input pin

TMOD.6
TMOD.2

C/T

Selects Timer or Counter operation. When set to 1, a Counter operation is
performed. When cleared to 0, the corresponding register will function as a
Timer.

TMOD.5
TMOD.1

M1

Selects the mode for Timer/Counter 0 or Timer/Counter 1, as shown in TMOD
description.

TMOD.4
TMOD.0

M0

Selects the mode for Timer/Counter 0 or Timer/Counter 1, as shown in TMOD
description.

Table 6-21: The TMOD Register Bits Description

M1

M0

Mode

Function

0

0

Mode 0

13-bit Counter/Timer with 5 lower bits in the TL0 or TL1 register and the
remaining 8 bits in the TH0 or TH1 register (for Timer 0 and Timer 1,
respectively). The 3 high order bits of TL0 and TL1 are held at zero.

0

1

Mode 1

16-bit Counter/Timer.

1

0

Mode2

8-bit auto-reload Counter/Timer. The reload value is kept in TH0 or TH1,
while TL0 or TL1 is incremented every machine cycle. When tl(x)
overflows, a value from th(x) is copied to tl(x).

1

1

Mode3

If Timer 1 m1 and m0 bits are set to '1', Timer 1 stops. If Timer 0 m1 and
m0 bits are set to '1', Timer 0 acts as two independent 8 bit
Timer/Counters.

Table 6-22: Timers/Counters Mode Description

TL0 is affected by tr0 and gate control bits, and sets TF0 flag on overflow.

TH0 is affected by tr1 bit, and sets TF1 flag on overflow.

Timer/Counter Control Register (TCON)

MSB

LSB

TF1

TR1

TF0

TR0

IE1

IT1

IE0

IT0

Table 6-23: The TCON Register

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