5xx

The MPC5xx family of processors such as the MPC555 and MPC565 are 32-bit PowerPC embedded microprocessors that operate between 40 and 66 MHz and are frequently used in automotive applications including engine and transmission controllers. Delphi Corporation use either the MPC561 or MPC565 in the engine controllers they supply to General Motors, with nearly all 2009 model GM North America vehicles now using an MPC5xx in the engine controller. Bosch also used the MPC5xx throughout the ME(D)-9 series of Gasoline Engine Controllers, EDC-16 series of Diesel Engine Controllers as did the Cummins B series diesel engine ECU.
They are generally considered microcontrollers because of their integrated peripheral set and their unusual architecture: no MMU, large on-chip SRAM and very large (as much as 1 MB) low latency access on-chip flash memories, which means their architecture is tailored to control applications. Instead of a block-address translation and a hardware-driven, fixed-page address translation prescribed by the first PowerPC specification, the 5xx cores provided a software-driven translation mechanism that supported variable page sizes. This model is the basis for the embedded MMU model in the current Power ISA specification.
MPC5xx – All PowerPC 5xx family processors share this common naming scheme.
The development of the PowerPC 5xx family is discontinued in favour for the more flexible and powerful PowerPC 55xx family.

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