MPC555CME Freescale Semiconductor, MPC555CME Datasheet - Page 693

• Manufacturer Part Number: MPC555CME
• Description: KIT EVALUATION FOR MPC555
• Manufacturer: Freescale Semiconductor
• Type: Microcontrollerr

Specifications of MPC555CME

• Contents: Module Board, Installation Guide, Power Supply, Cable, Software and more
• Processor To Be Evaluated: MPC555
• Data Bus Width: 32 bit
• Interface Type: RS-232
• For Use With/related Products: MPC555
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

20.1 Features
20.2 Block Diagram
MPC555 / MPC556
USER’S MANUAL
The MPC555 / MPC556 contains two static random access memory (SRAM) modules:
a 16-Kbyte module and a 10-Kbyte module. The SRAM modules provide the micro-
controller unit (MCU) with fast (one cycle access), general-purpose memory. The
SRAM can be read or written as either bytes, half words, or words.
Each SRAM module is built with a series of 4-Kbyte blocks and occupies a continuous
block of memory. For a RAM size array block of less than 4 Kbytes (e.g., the 2-Kbyte
array in the 10-Kbyte SRAM module), the remaining 2 Kbytes are unimplemented and
unusable.
The SRAM modules are accessible to the CPU and other bus masters via the L-bus
on the CPU chip. To improve access time, each SRAM module resides on a separate
bus interface unit (BIU). Each BIU has its own module control register.
Figure 20-1
• One-cycle access
• Byte, half-word, or word read/write accesses
• Individual protection control bits provided for 4-Kbyte block boundaries
• Two-cycle access for power savings
• Low power standby operation for data retention
• Supports pipelining
— read only region
— data only region
— user/supervisor
— V
Power Gone
L-bus
DDI
STATIC RANDOM ACCESS MEMORY (SRAM)
shows the major components of an SRAM module.
= 0, no read/writes to the SRAM; VDDSRAM = 3.3 V to retain data
STATIC RANDOM ACCESS MEMORY (SRAM)
Figure 20-1 SRAM Block Diagram
(Maximum 16 Kbytes)
Rev. 15 October 2000
SRAM Array
SECTION 20
Keep-Alive Power
MOTOROLA
20-1