EM78P5840/5841/5842
8-bit Micro-controller
Fosc
1:2
To PWM1IF
1:8
1:32
1:64
MUX
reset
Period
Match
TMR1X
Comparator
T1P0 T1P1
T1EN
PRD1
Data Bus
Data Bus
PRD2
T2P0 T2P1 T2EN
Comparator
reset
Period
Match
Fosc
1:2
TMR2X
1:8
1:32
1:64
MUX
To PWM2IF
*TMR1X = TMR1H + TMR1L;
*TMR2X = TMR2H +TMR2L
Fig.12 TMRX Block Diagram
• Fosc: Input clock.
• Prescaler (T1P0 and T1P1): Options of 1:2, 1:8, 1:32, and 1:64 are defined by TMRX. It is cleared when
any type of reset occurs.
• TMR1X (TMR1H/TWR1L):Timer X register; TMRX is increased until it matches with PRDX, and then is
reset to 0. TMRX cannot be read.
• PRDX (PRD1): PWM period register.
When defining TMRX, refer to the related registers of its operation as shown in prescale register. It must be
noted that the PWMX bits must be disabled if their related TMRXs are employed. That is, bit 6 of the
PWMCON register must be set to ‘0’.
Related Control Registers(R5 PAGE3) of TMR1 and TMR2
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3 Bit 2
Bit 1 Bit 0
T1P1 T1P0
PWM2E PWM1E T2EN T1EN T2P1 T2P0
Timer programming procedures/steps
Load PRDX with the TIMER period.
Enable interrupt function by writing IOCF PAGE0, if required
Load a desired value to PWMCON with the TMRX prescaler value and enable both TMRX and disable
PWMX.
__________________________________________________________________________________________________________________________________________________________________
* This specification is subject to change without notice.
33
2004/11/10 V2.6
ELAN [ ELAN MICROELECTRONICS CORP ]
