20-668-0024 Rabbit Semiconductor, 20-668-0024 Datasheet - Page 58

• Manufacturer Part Number: 20-668-0024
• Description: IC CPU RABBIT4000 128-LQFP
• Manufacturer: Rabbit Semiconductor

Specifications of 20-668-0024

• Processor Type: Rabbit 4000 8-bit
• Speed: 60MHz
• Voltage: 2.5V, 2.7V, 3V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 128-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Other names: 20-668-0022; 316-1078

The two address bits used to select the bank can be inverted in MBxCR, which enables
mapping different sections of a memory device larger than the current memory bank into
memory. An example of this feature is shown in Figure 5-4.
Figure 5-4. Mapping Different Sections of a Memory Device
Larger Than the Current Memory Bank
It is possible to extend the timing of the /OE and/or /WE strobes by one half of a clock.
This provides slightly longer strobes for slower memories; see the timing diagrams in
Chapter 28. These options are available in MTCR.
It is possible to force /CS1 to be always active in MMIDR; enabling this will cause con-
flicts only if a device shares a /OE or /WE strobe with another device. This option allows
faster access to particular memory devices.
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Rabbit 4000 Microprocessor User’s Manual