General Purpose Timer Modules
MCF5253 Reference Manual, Rev. 1
Freescale Semiconductor
11-3
When the timer reaches the reference value, the REF bit in the TER register is set and issues an interrupt
if the output reference interrupt (ORI) enable bit in TMR is set.
11.5.3
Configuring the Timer for Output Mode (TIMER0)
Timer0 can send an output signal on the timer output (TOUT0) pin when it reaches the reference value as
selected by the output mode (OM) bit in the TMR. This signal can be an active-low pulse or a toggle of
the current output under program control.
11.6
General-Purpose Timer Memory Map and Register Definitions
Users can modify the timer registers at any time.
shows the timer memory map.
11.6.1
Timer Mode Registers (TMR0, TMR1)
The TMR is a 16-bit memory-mapped register. This register programs the various timer modes and is
cleared by reset.
Table 11-1. Memory Map for General-Purpose Timers
Timer 0 Address
Timer 1 Address
Timer Module Registers
MBAR+$140
MBAR+$180
Timer Mode Register (TMRn)
MBAR+$144
MBAR+$184
Timer Reference Register (TRRn)
MBAR+$148
MBAR+$188
Timer Capture Register (TCRn)
MBAR+$14C
MBAR+$18C
Timer Counter (TCNn)
MBAR+$151
MBAR+$191
Reserved
Timer Event Register (TERn)
Address
MBAR+$140
MBAR+$180
Access: Supervisor or User read/write
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
PRESCALER VALUE (PS7–PS0)
CE1
CE0
OM
ORI
FRR
CLK1 CLK0
RESET
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 11-2. Timer Mode Register (TMRn)
Table 11-2. Timer Mode Register (TMRn) Field Descriptions
Bit Name
Description
15–8
PS
The Prescaler Value is programmed to divide the clock input by values from 1 to 256. The value 00000000 divides
the clock by 1; the value 11111111 divides the clock by 256.
Prescalar value = $[PS7
–
PS0] + 1
7–6
CE
These bits have no function and should be set to 00.
Summary of Contents for MCF5253
Page 1: ...Document Number MCF5253RM Rev 1 08 2008 MCF5253 Reference Manual...
Page 26: ...MCF5253 Reference Manual Rev 1 xxvi Freescale Semiconductor...
Page 32: ...MCF5253 Reference Manual Rev 1 xxxii Freescale Semiconductor...
Page 46: ...MCF5253 Introduction MCF5253 Reference Manual Rev 1 1 14 Freescale Semiconductor...
Page 62: ...Signal Description MCF5253 Reference Manual Rev 1 2 16 Freescale Semiconductor...
Page 98: ...Instruction Cache MCF5253 Reference Manual Rev 1 5 10 Freescale Semiconductor...
Page 104: ...Static RAM SRAM MCF5253 Reference Manual Rev 1 6 6 Freescale Semiconductor...
Page 128: ...Synchronous DRAM Controller Module MCF5253 Reference Manual Rev 1 7 24 Freescale Semiconductor...
Page 144: ...Bus Operation MCF5253 Reference Manual Rev 1 8 16 Freescale Semiconductor...
Page 176: ...System Integration Module SIM MCF5253 Reference Manual Rev 1 9 32 Freescale Semiconductor...
Page 198: ...Analog to Digital Converter ADC MCF5253 Reference Manual Rev 1 12 6 Freescale Semiconductor...
Page 246: ...DMA Controller MCF5253 Reference Manual Rev 1 14 18 Freescale Semiconductor...
Page 282: ...UART Modules MCF5253 Reference Manual Rev 1 15 36 Freescale Semiconductor...
Page 344: ...Audio Interface Module AIM MCF5253 Reference Manual Rev 1 17 46 Freescale Semiconductor...
Page 362: ...I2 C Modules MCF5253 Reference Manual Rev 1 18 18 Freescale Semiconductor...
Page 370: ...Boot ROM MCF5253 Reference Manual Rev 1 19 8 Freescale Semiconductor...