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* Module configuration register:
* Timer1 module is set for normal operation, ignore FREEZE.
* Supervisor/user timer1 registers unrestricted.
* Interrupt arbitration at priority $03.
MOVE.W
#$0003,MCR1(A0)
* Initialize timer1 interrupt level to 2 and vector to $0F
MOVE.W
#$020F,IR1(A0)
* Initialize preload 1 to 3
MOVE.W
#$0003,PRLD11(A0)
* Initialize the compare register to 0
CLR.W
COM1(A0)
* Control register 1:
* Enable timer1, no interrupts are enabled, TGATE signal has no effect.
* Use the selected clock for the counter clock, and enable it.
* Selected clock is 1/2 system's freq. Square-wave generation, toggle TOUT.
MOVE.W
#$8205,CR1(A0)
***************************************************************************
END
***************************************************************************
***************************************************************************
* MC68340 basic timer module register initialization example code.
* This code is used to initialize the 68340's internal timer module
* registers, providing basic functions for operation.
* It sets up timer1 for pulse-width measurement. In this mode, the number
* of clock cycles during a particular event are counted. The event is
* defined by the assertion and negation of TGATE.
***************************************************************************
***************************************************************************
* equates
***************************************************************************
MBAR
EQU $0003FF00 Address of SIM40 Module Base Address Reg.
MODBASE EQU $FFFFF000 SIM40 MBAR address value
***************************************************************************
* Timer1 module equates
TIMER1
EQU $600
MCR1
EQU $0
MOTOROLA
Freescale Semiconductor, Inc.
Offset from MBAR for timer1 module regs
MCR for timer1
MC68340 USER'S MANUAL
For More Information On This Product,
Go to: www.freescale.com
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