668-0010 Rabbit Semiconductor, 668-0010 Datasheet - Page 33

• Manufacturer Part Number: 668-0010
• Description: IC MPU RABIT3000 55.5MHZ 128LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0010

• Rohs Status: RoHS non-compliant
• Processor Type: Rabbit 3000 8-Bit
• Speed: 55.5MHz
• Voltage: 2.5V, 2.7V, 3V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 128-LQFP
• Features: -
• Other names: 316-1016

3. R
B
ESET AND
OOTSTRAP
3.1 Overview
The Rabbit 3000’s /RESET pin initializes everything in the processor except for the real-
time clock registers. If a write cycle is in progress, it waits until the write cycle is com-
pleted to avoid potential memory corruption.
After reset, the Rabbit 3000 checks the state of the SMODE pins. Depending on their
state, it either begins normal operation by fetching instruction bytes from /CS0 and /OE0,
or it enters a special bootstrap mode where it fetches bytes from either Serial Port A or the
slave port. In this mode, bytes can be written to internal registers to set up the Rabbit 3000
for a particular configuration, or to memory to load a program. The processor can begin
normal operation once the bootstrap operation is completed.
3.1.1 Block Diagram
Chapter 3 Reset and Bootstrap
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