20-101-0554 Rabbit Semiconductor, 20-101-0554 Datasheet - Page 81

• Manufacturer Part Number: 20-101-0554
• Description: COMPUTER SNGL BD BL2000 BOTT MNT
• Manufacturer: Rabbit Semiconductor

Specifications of 20-101-0554

• Module/board Type: Single Board Computer Module
• For Use With/related Products: BL2000
• Lead Free Status / RoHS Status: Vendor undefined / Vendor undefined

C.2.4 Reset Generator
The BL2000 uses a reset generator, U4, to reset the Rabbit 2000 microprocessor when the
voltage drops below the voltage necessary for reliable operation. The reset occurs between
4.50 V and 4.75 V, typically 4.63 V. The reset can be initiated either externally or by a
watchdog timeout (
User’s Manual
NOTE: The Dynamic C function chkWDTO is not able to detect whether a watchdog
timeout has occurred on the BL2000. The GCSR status bits are read and stored by the
BIOS, and the reset status bit would normally change once a reset has occurred. How-
ever, since WDTOUT is tied to the reset generator, a watchdog timeout forces a hard-
ware reset, followed by the BIOS reading and storing the status bits corresponding to
power-up or reset.
To use chkWDTO to detect a watchdog timeout, remove D15 (located on the bottom
side of the BL2000).
WDTOUT
) on the Rabbit 2000 microprocessor.
Figure C-4. Reset Generator
W
W
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