RM0367 Rev 7 649/1043
RM0367 System window watchdog (WWDG)
650
26.5.2 WWDG configuration register (WWDG_CFR)
Address offset: 0x004
Reset value: 0x0000 007F
26.5.3 WWDG status register (WWDG_SR)
Address offset: 0x008
Reset value: 0x0000 0000
Bits 31:8 Reserved, must be kept at reset value.
Bit 7 WDGA: Activation bit
This bit is set by software and only cleared by hardware after a reset. When WDGA = 1, the
watchdog can generate a reset.
0: Watchdog disabled
1: Watchdog enabled
Bits 6:0 T[6:0]: 7-bit counter (MSB to LSB)
These bits contain the value of the watchdog counter, decremented every
(4096 x 2
WDGTB
[1:0]
) PCLK cycles. A reset is produced when it is decremented from 0x40 to
0x3F (T6 becomes cleared).
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res.
1514131211109876543210
Res. Res. Res. Res. Res. Res. EWI WDGTB[1:0] W[6:0]
rs rw rw rw rw rw rw rw rw rw
Bits 31:10 Reserved, must be kept at reset value.
Bit 9 EWI: Early wakeup interrupt
When set, an interrupt occurs whenever the counter reaches the value 0x40. This interrupt is
only cleared by hardware after a reset.
Bits 8:7 WDGTB[1:0]: Timer base
The time base of the prescaler can be modified as follows:
00: CK counter clock (PCLK div 4096) div 1
01: CK counter clock (PCLK div 4096) div 2
10: CK counter clock (PCLK div 4096) div 4
11: CK counter clock (PCLK div 4096) div 8
Bits 6:0 W[6:0]: 7-bit window value
These bits contain the window value to be compared with the down-counter.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res.
1514131211109876543210
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. EWIF
rc_w0