668-0011 Rabbit Semiconductor, 668-0011 Datasheet - Page 50

• Manufacturer Part Number: 668-0011
• Description: IC MPU RABIT3000A 55.5MHZ128LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 668-0011

• 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: 316-1043

Either of the two most significant address bits (which are used to select the quadrant) can
be inverted, providing the ability to bank-switch other pages from a larger memory device
into the same memory bank.
Code is executed in the 64 KB logical memory space, which is divided into four segments:
root, data, stack, and XPC. The root segment is mapped directly to physical address
0x00000, while the data and stack segments can be mapped to 4 KB boundaries anywhere
in the physical space. The boundaries between the root and data segments and the data and
stack segments can be adjusted in 4 KB blocks as well.
The XPC segment is a fixed 8 KB and points to a physical memory address specified in
the XPC register. It is possible to run code in the XPC window, providing an easy means
of storing and executing code beyond the 64 KB logical memory space. Special call and
return instructions to physical addresses are provided that automatically update the XPC
register as necessary.
Figure 5-2. Logical and Physical Memory Mapping
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Rabbit 3000 Microprocessor User’s Manual