Functional Description
13-14
ADSP-BF50x Blackfin Processor Hardware Reference
Zero Marker Events
There are three status bits
CZMII
,
CZMEII
and
CZMZII
associated with zero
marker events, as described in
“Zero Marker (Push Button) Operation” on
page 13-9
. Each of these events can optionally generate an interrupt
request, if enabled by the corresponding
CZMIE
,
CZMEIE
and
CZMZIE
bits in
the
CNT_IMASK
register.
Capturing Timing Information
To calculate speed, many applications may wish to measure the time
between two count events—in addition to accurately counting encoder
pulses. For more accuracy, particularly at very low speeds, it is also neces-
sary to obtain the time that has elapsed since the last count event. This
additional information allows for estimating how much the GP counter
has advanced since the last counter event.
For this purpose, the GP counter has an internal signal that connects to
the alternate capture input (
TACIx
) of one of the GP timers. It is func-
tional in all modes, with the exception of the timed direction mode. Refer
to “Internal Interfaces” in
Chapter 9, “General-Purpose Ports”
for infor-
mation regarding which GP timer(s) are associated with which GP
counter module(s) for your device.
In order to use the timing measurements, the associated GP timer must be
used in the
WDTH_CAP
mode. The alternate capture input is selected by set-
ting the
TIN_SEL
bit in the GP timer's
TIMER_CONFIG
register. For more
information about the GP timers and their operating modes, refer to the
General-Purpose Timer
chapter.
Capturing Time Interval Between
Successive Counter Events
When the only timing information of interest is the interval between suc-
cessive count events, the associated timer should be programmed in
WDTH_CAP
mode with
PULSE_HI
= 1,
PERIOD_CNT
= 1 and
TIN_SEL
= 1.
Содержание EZ-KIT Lite ADSP-BF506F
Страница 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 132: ...Unique Information for the ADSP BF50x Processor 4 22 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 342: ...Unique Information for the ADSP BF50x Processor 7 106 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 484: ...Unique Information for the ADSP BF50x Processor 10 60 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 493: ...ADSP BF50x Blackfin Processor Hardware Reference 11 9 Core Timer Unique Information for the ADSP BF50x Processor None ...
Страница 494: ...Unique Information for the ADSP BF50x Processor 11 10 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 506: ...Unique Information for the ADSP BF50x Processor 12 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 544: ...Unique Information for the ADSP BF50x Processor 13 38 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 712: ...Unique Information for the ADSP BF50x Processor 16 62 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 972: ...Unique Information for the ADSP BF50x Processor 20 38 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Страница 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...