SAB80C517-16-N-T40/85 Siemens Semiconductor Group, SAB80C517-16-N-T40/85 Datasheet - Page 43

• Manufacturer Part Number: SAB80C517-16-N-T40/85
• Description: 8-Bit CMOS Single-Chip Microcontroller
• Manufacturer: Siemens Semiconductor Group

SAB 80C517/80C537
Figure 11
Block Diagram of the Programmable Watchdog Timer
Oscillator Watchdog
The oscillator watchdog monitors the on-chip quartz oscillator. A detected oscillator failure
(f
< appr. 300 kHz) causes a hardware reset. The reset state is held until the on-chip
OSC
oscillator is working again. The oscillator watchdog feature is enabled by a high level at pin
OWE (pin 69). An oscillator watchdog reset sets status flag OWDS which can be examined and
modified by software. Figure 12 shows a block diagram of the oscillator watchdog.
Figure 12
Functional Block Diagram of the Oscillator Watchdog
Semiconductor Group
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