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Philips Semiconductors
Preliminary User Manual
LPC2119/2129/2292/2294
ARM-based Microcontroller
Prescale Counter Register (PC: TIMER0 - T0PC: 0xE0004010; TIMER1 - T1PC: 0xE0008010)
The 32-bit Prescale Counter controls division of pclk by some constant value before it is applied to the Timer Counter. This allows
control of the relationship of the resolution of the timer versus the maximum time before the timer overflows. The Prescale
Counter is incremented on every pclk. When it reaches the value stored in the Prescale Register, the Timer Counter is
incremented and the Prescale Counter is reset on the next pclk. This causes the TC to increment on every pclk when PR = 0,
every 2 pclks when PR = 1, etc.
Match Registers (MR0 - MR3)
The Match register values are continuously compared to the Timer Counter value. When the two values are equal, actions can
be triggered automatically. The action possibilities are to generate an interrupt, reset the Timer Counter, or stop the timer. Actions
are controlled by the settings in the MCR register.
Match Control Register (MCR: TIMER0 - T0MCR: 0xE0004014; TIMER1 - T1MCR: 0xE0008014)
The Match Control Register is used to control what operations are performed when one of the Match Registers matches the Timer
Counter. The function of each of the bits is shown in Table 159.
Table 159: Match Control Register (MCR: TIMER0 - T0MCR: 0xE0004014; TIMER1 - T1MCR: 0xE0008014)
MCR
Function
Description
Reset
Value
0
Interrupt on MR0
When one, an interrupt is generated when MR0 matches the value in the TC. When
zero this interrupt is disabled.
0
1
Reset on MR0
When one, the TC will be reset if MR0 matches it. When zero this feature is disabled.
0
2
Stop on MR0
When one, the TC and PC will be stopped and TCR[0] will be set to 0 if MR0 matches
the TC. When zero this feature is disabled.
0
3
Interrupt on MR1
When one, an interrupt is generated when MR1 matches the value in the TC. When
zero this interrupt is disabled.
0
4
Reset on MR1
When one, the TC will be reset if MR1 matches it. When zero this feature is disabled.
0
5
Stop on MR1
When one, the TC and PC will be stopped and TCR[0] will be set to 0 if MR1 matches
the TC. When zero this feature is disabled.
0
6
Interrupt on MR2
When one, an interrupt is generated when MR2 matches the value in the TC. When
zero this interrupt is disabled.
0
7
Reset on MR2
When one, the TC will be reset if MR2 matches it. When zero this feature is disabled.
0
8
Stop on MR2
When one, the TC and PC will be stopped and TCR[0] will be set to 0 if MR2 matches
the TC. When zero this feature is disabled.
0
9
Interrupt on MR3
When one, an interrupt is generated when MR3 matches the value in the TC. When
zero this interrupt is disabled.
0
10
Reset on MR3
When one, the TC will be reset if MR3 matches it. When zero this feature is disabled.
0
11
Stop on MR3
When one, the TC and PC will be stopped and TCR[0] will be set to 0 if MR3 matches
the TC. When zero this feature is disabled.
0