10.1 Introduction
The Control Law Accelerator extends the capabilities of the C28x CPU by adding parallel processing. Time-
critical control loops serviced by the CLA can achieve low ADC sample to output delay. Thus, the CLA enables
faster system response and higher frequency control loops. Utilizing the CLA for time-critical tasks frees up the
main CPU to perform other system and communication functions concurrently.
10.1.1 Features
The following is a list of major features of the CLA:
• C compilers are available for CLA software development.
• Clocked at the same rate as the main CPU (SYSCLKOUT).
• An independent architecture allowing CLA algorithm execution independent of the main C28x CPU.
– Complete bus architecture:
• Program Address Bus (PAB) and Program Data Bus (PDB)
• Data Read Address Bus (DRAB), Data Read Data Bus (DRDB), Data Write Address Bus (DWAB), and
Data Write Data Bus (DWDB)
– Independent eight stage pipeline.
– 12-bit program counter (MPC)
– Four 32-bit result registers (MR0-MR3)
– Two 16-bit auxiliary registers (MAR0, MAR1)
– Status register (MSTF)
• Instruction set includes:
– IEEE single-precision (32-bit) floating-point math operations
– Floating-point math with parallel load or store
– Floating-point multiply with parallel add or subtract
– 1/X and 1/sqrt(X) estimations
– Data type conversions.
– Conditional branch and call
– Data load/store operations
• The CLA program code can consist of up to eight tasks or interrupt service routines
– The start address of each task is specified by the MVECT registers.
– No limit on task size as long as the tasks fit within the configurable CLA program memory space.
– One task is serviced at a time until its completion. There is no nesting of tasks.
– Upon task completion a task-specific interrupt is flagged within the PIE.
– When a task finishes the next highest-priority pending task is automatically started.
• Task trigger mechanisms:
– C28x CPU via the IACK instruction
– Task1 to Task8: trigger sources from peripherals connected to the shared bus on which the CLA assumes
secondary ownership.
• Memory and Shared Peripherals:
– Two dedicated message RAMs for communication between the CLA and the main CPU.
– The C28x CPU can map CLA program and data memory to the main CPU space or CLA space.
10.1.2 CLA Related Collateral
Foundational Materials
•
(Video)
•
(Video)
•
CLA usage in Valley Switching Boost Power Factor Correction (PFC) Reference Design
(Video)
•
Control Law Accelerator Debug in CCS 4
(Video)
•
Control Law Accelerator Example Framework
(Video)
•
Enhancing the Computational Performance of the C2000 Microcontroller Family Application Report
Control Law Accelerator (CLA)
570
TMS320x2806x Microcontrollers
SPRUH18I – JANUARY 2011 – REVISED JUNE 2022
Copyright © 2022 Texas Instruments Incorporated
Содержание TMS320 2806 Series
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