
DMA Timers (DTIM0–DTIM3)
Freescale Semiconductor
29-9
29.3.4
Output Mode
When a timer reaches the reference value selected by DTRR, it can send an output signal on DT
n
OUT.
DT
n
OUT can be an active-low pulse or a toggle of the current output, as selected by the DTMR
n
[OM] bit.
29.3.5
IEEE 1588 Support
The DMA timers on this device can use the Ethernet assembly’s IEEE-1588 timebase count value as its
clock source. This feature supports triggering events via processor interrupts or DMA requests based on
network time values.
29.4
Initialization/Application Information
The general-purpose timer modules typically, but not necessarily, follow this program order:
•
The DTMR
n
and DTXMR
n
registers are configured for the desired function and behavior.
— Count and compare to a reference value stored in the DTRR
n
register
— Capture the timer value on an edge detected on DT
n
IN
— Configure DT
n
OUT output mode
— Increment counter by 1 or by 65,537 (16-bit mode)
— Enable/disable interrupt or DMA request on counter reference match or capture edge
•
The DTMR
n
[CLK] register is configured to select the clock source to be routed to the prescaler.
— Internal bus clock (can be divided by 1 or 16)
— DT
n
IN, the maximum value of DT
n
IN is 1/5 of the internal bus clock, as described in the
device’s electrical characteristics
NOTE
DT
n
IN may not be configured as a clock source when the timer capture
mode is selected or indeterminate operation results.
•
The 8-bit DTMR
n
[PS] prescaler value is set.
•
Using DTMR
n
[RST], counter is cleared and started.
•
Timer events are managed with an interrupt service routine, a DMA request, or by a software
polling mechanism.
29.4.1
Code Example
The following code provides an example of how to initialize and use DMA Timer0 for counting time-out
periods.
DTMR0 EQU 0xFC07_0000 ;Timer0 mode register
DTMR1 EQU 0xFC07_4000 ;Timer1 mode register
DTRR0 EQU 0xFC07_0004 ;Timer0 reference register
DTRR1 EQU 0xFC07_4004 ;Timer1 reference register
DTCR0 EQU 0xFC07_0008 ;Timer0 capture register
DTCR1 EQU 0xFC07_4008 ;Timer1 capture register
DTCN0 EQU 0xFC07_000C ;Timer0 counter register
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...