![Texas Instruments AM1808 Скачать руководство пользователя страница 353](http://html.mh-extra.com/html/texas-instruments/am1808/am1808_technical-reference-manual_1094558353.webp)
Registers
353
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Programmable Real-Time Unit Subsystem (PRUSS)
Table 13-37. CYCLECNT Register Field Descriptions
Bit
Field
Type
Reset
Description
31-0
CYCLECOU
NT
R/WC
0
This value is incremented by 1 for every cycle during which the PRU is
enabled and the counter is enabled (both bits "ENABLE" and
"COUNTENABLE" set in the PRU control register).
Counting halts while the PRU is disabled or counter is disabled, and resumes
when re-eneabled. Counter clears the "COUNTENABLE" bit in the PRU
control register when the count reaches 0xFFFFFFFF. (Count does does not
wrap). The register can be read at any time. The register can be cleared
when the counter or PRU is disabled. Clearing this register also clears the
PRU Stall Count Register.
13.8.1.3.5 STALLCNT Register (Offset = 10h)
This register counts the number of cycles for which the PRU has been enabled, but unable to fetch a new
instruction. It is linked to the Cycle Count Register (0x0C) such that this register reflects the stall cycles
measured over the same cycles as counted by the cycle count register. Thus the value of this register is
always less than or equal to cycle count.
Figure 13-28. STALLCNT Register
31
0
STALLCOUNT
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 13-38. STALLCNT Register Field Descriptions
Bit
Field
Type
Reset
Description
31-0
STALLCOUN
T
R
0
This value is incremented by 1 for every cycle during which the PRU is
enabled and the counter is enabled (both bits "ENABLE" and
"COUNTENABLE" set in the PRU control register), and the PRU was unable
to fetch a new instruction for any reason.
Counting halts while the PRU is disabled or the counter is disabled, and
resumes when re-enabled. The register can be read at any time. The register
is cleared when PRU Cycle Count Register is cleared.
13.8.1.3.6 CONTABBLKIDX0 Register (Offset = 20h)
This register is used to set the block indices which are used to modify entries 24 and 25 in the PRU
Constant Table. This register can be written by the PRU whenever it needs to change to a new base
pointer for a block in the State / Scratchpad RAM. This function is useful since the PRU is often
processing multiple processing threads which require it to change contexts. The PRU can use this register
to avoid requiring excessive amounts of code for repetitive context switching. The format of this register is
as follows:
Figure 13-29. CONTABBLKIDX0 Register
31
20
19
16
RESERVED
C25
R-0
R/W-0
15
4
3
0
RESERVED
C24
R-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset