
Watchdog Timer Module
27-4
Freescale Semiconductor
27.2.2
Watchdog Modulus Register (WMR)
The WMR register determines the timer modulus reload value.
27.2.3
Watchdog Count Register (WCNTR)
The WCNTR register provides visibility to the watchdog counter value. The timeout value for the
watchdog timer is determined from the following equation:
Eqn. 27-1
Thus, the maximum timeout is 4096
×
2
16
/ f
sys/3
= 3.36 seconds at 80 MHz internal bus frequency.
Address: 0xFC09_8002
Access: Supervisor
read/write
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
WM
W
Reset
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Figure 27-3. Watchdog Modulus Register (WMR)
Table 27-4. WMR Field Descriptions
Field
Description
15–0
WM
Watchdog modulus. Contains the modulus that is reloaded into the watchdog counter by a service sequence. After
written, the WM[15:0] field is not affected by further writes except in halted mode. Writing to WMR immediately loads
the new modulus value into the watchdog counter. The new value is also used at the next and all subsequent reloads.
Reading WMR returns the value in the modulus register.
Reset initializes the WM[15:0] field to 0xFFFF.
Note: The prescaler counter is reset anytime a new value is loaded into the watchdog counter and also during reset.
Address: 0xFC09_8004
Access: User read/write
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
WC
W
Reset
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Figure 27-4. Watchdog Count Register (WCNTR)
Table 27-5. WCNTR Field Descriptions
Field
Description
15–0
WC
Watchdog count field. Reflects the current value in the watchdog counter. Reading the 16-bit WCNTR with two 8-bit
reads is not guaranteed to return a coherent value. Writing to WCNTR has no effect, and write cycles are terminated
normally.
WDT timeout
4096
WCNTR
×
f
sys 3
⁄
----------------------------------------
=
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...