Differences

This shows you the differences between two versions of the page.

--- en:netzer:impulse [2014/08/16 17:57] – [Impulse handling with Netzer IO] svesch
+++ en:netzer:impulse [2025/06/11 20:42] (current) – external edit 127.0.0.1
@@ Line 3: / Line 3: @@
 Netzer is able to generate and capture signals at IO3 and SPI_INT.
-{{ :en:netzer:impulse_overview.gif?direct&600 |}}
+{{ :en:netzer:impulse_overview.gif?direct&700 |}}
 The image shows the structure of the impulse generator/capture.
@@ Line 21: / Line 21: @@
-===== Unsynchronized mode =====
+===== Examples =====
+Some of the examples below show both signals IO3 and SPI_INT.
+Of course impulse module can be configured to use only one of them.
+The examples below only show positive logic.
+Simply invert the signals to get negative logic examples.
+In the IO0 examples the IO0 trigger is configured for rising edge.
+Simply invert the IO0 signal to get falling edge examples.
+==== Generating impulses in continuous mode (Unsynchronized) ====
 The impulse timer is free running in this mode.
-IO0 interrupts will not reset the impulse timer.
+Changes on IO0 will not reset the impulse timer.
+{{ :en:netzer:impulse_compare_cont_unsync.gif?direct |}}
+==== Generating impulses in single mode (Unsynchronized) ====
+The impulse timer is free running in this mode.
+Changes on IO0 will not reset the impulse timer.
+{{ :en:netzer:impulse_compare_single_unsync.gif?direct |}}
+==== Generating impulses in "Triggered by IO0" mode (Unsynchronized) ====
+This mode shall not be used.
+==== Generating impulses in continuous mode (IO0 synchronized) ====
+This mode shall not be used.
+==== Generating impulses in single mode (IO0 synchronized) ====
+{{ :en:netzer:impulse_compare_single_sync.gif?direct |}}
+==== Generating impulses in "Triggered by IO0" mode (IO0 synchronized) ====
+{{ :en:netzer:impulse_compare_io0_sync.gif?direct |}}
+==== Measuring impulses in continuous mode (Unsynchronized) ====
+{{ :en:netzer:impulse_capture_cont_unsync.gif?direct |}}
+==== Measuring impulses in single mode (Unsynchronized) ====
+{{ :en:netzer:impulse_capture_single_unsync.gif?direct |}}
+==== Measuring impulses in "Triggered by IO0" mode (Unsynchronized) ====
+This mode shall not be used.
+==== Measuring impulses in continuous mode (IO0 synchronized) ====
+This mode shall not be used.
+==== Measuring impulses in single mode (IO0 synchronized) ====
+{{ :en:netzer:impulse_capture_single_sync.gif?direct |}}
-==== Generating impulses in continuous mode ====
+The second example shows the special case of an ultrasonic sensor like HC-SR04.
+This sensor needs a 10 µs impulse at the TRIG input which shall be connected to IO3.
+The pulse length of sensor singnal ECHO decodes the distance to the detected object.
+The signal must be connected to IO0 and SPI_INT.
+IO0 must be configured for rising trigger edge, SPI_INT for falling capture edge.
+{{ :en:netzer:impulse_capture_io0_sync2.gif?direct |}}
+==== Measuring impulses in „Triggered by IO0“ mode (IO0 synchronized) ====
+In this mode the periode of periodic signals or pulse length can be measured.
+Connect the signal to measure to IO0 and IO3 or SPI_INT or both.
+For period length the IO0 trigger edge and the capture edge must be equal (like IO3 in image below).
+For positive pulses the IO0 trigger edge must be rising, the capture edge falling edge (like SPI_INT in image below).
+For negative pulses the IO0 trigger edge must be falling, the capture edge rising edge.
+{{ :en:netzer:impulse_capture_io0_sync.gif?direct |}}