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ATSAM2133B

2694A–DRMSD–05/03

P16 Control Processor

and I/O Functions

The P16 control processor is a general-purpose 16-bit CISC processor core that runs

from external memory. It includes 256 words of local RAM data memory.

The P16 control processor writes to the parameter RAM blocks within the synthe-

sis/DSP core in order to control the synthesis process. In a typical application, the P16

control processor parses and interprets incoming commands from the MIDI UART or

from the MPU-401 interface and then controls the Synthesis/DSP by writing into the

parameter RAM banks in the DSP core. Slowly-changing synthesis functions, such as

LFOs, are implemented in the P16 control processor by periodically updating the DSP

parameter RAM variables.

The P16 control processor interfaces with other peripheral devices, such as the system

control and status registers, the on-chip MIDI UART, the on-chip timers and the MPU-

401 interface through specialized intelligent peripheral I/O logic. This I/O logic auto-

mates many of the system I/O transfers to minimize the amount of overhead processing

required from the P16.

The MPU-401 interface is implemented using one address line (A0), a chip select signal,

read and write strobes from the host and an 8-bit data bus (D0 - D7).

Karaoke and keyboard applications can take advantage of the 8-bit MPU-401 interface

to communicate with the ATSAM2133B at high speed, with the MIDI IN and MIDI OUT

signals remaining available.

Memory Management

Unit (MMU)

The Memory Management Unit (MMU) block allows external ROM/Flash and/or internal

32K x 16 RAM memory resources to be shared between the synthesis/DSP and the P16

control processor. This allows a single device (i.e., internal RAM) to serve as delay lines

for the synthesis/DSP and as data memory for the P16 control processor.