10.3.2 CLA Program Memory
The behavior of the program memory depends on the state of the MMEMCFG[PROGE] bit. This bit controls
whether the memory is mapped to CLA space or CPU space.
•
MMEMCFG[PROGE] == 0
In this case the memory is mapped to the CPU. The CLA will be halted and no tasks should be incoming.
– Any CLA fetch will be treated as an illegal opcode condition as described in
. This condition
will not occur if the proper procedure is followed to map the program memory.
– CLA reads and writes cannot occur
– The memory block behaves as any normal RAM block mapped to CPU memory space.
Priority of accesses are (highest priority first):
1. CPU data write, program write, debug write
2. CPU data read, program read, debug read
3. CPU fetch, program read
•
MMEMCFG[PROGE] == 1
In this case the memory block is mapped to CLA space. The CPU can only make debug accesses.
– CLA reads and writes cannot occur
– CLA fetches are allowed
– CPU fetches return 0 which is an illegal opcode and will cause an ITRAP interrupt.
– CPU data reads and program reads return 0
– CPU data writes and program writes are ignored
Priority of accesses are (highest priority first):
1. CLA fetch
2. CPU debug write
3. CPU debug read
Note
Because the CLA fetch has higher priority than CPU debug reads, it is possible for the CLA to
permanently block debug accesses if the CLA is executing in a loop. This might occur when initially
developing CLA code due to a bug. To avoid this issue, the program memory will return all 0x0000
for CPU debug reads (ignore writes) when the CLA is running. When the CLA is halted or idle then
normal CPU debug read and write access can be performed.
10.3.3 CLA Data Memory
There are three independent data memory blocks. The behavior of the data memory depends on the state of
the MMEMCFG[RAM0E], MMEMCFG[RAM1E] and MMEMCFG[RAM2E] bits. These bits determine whether the
memory blocks are mapped to CLA space or CPU space.
•
MMEMCFG[RAMxE] == 0, MMEMCFG[RAMxCPUE] = 0/1
In this case the memory block is mapped to the CPU.
– CLA fetches cannot occur to this block.
– CLA reads return 0.
– CLA writes are ignored.
– The memory block behaves as any normal RAM block mapped to the CPU memory space.
Control Law Accelerator (CLA)
576
TMS320x2806x Microcontrollers
SPRUH18I – JANUARY 2011 – REVISED JUNE 2022
Copyright © 2022 Texas Instruments Incorporated
Содержание TMS320 2806 Series
Страница 2: ......