AVAL APX-3302, Руководство пользователя

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APX-3302 User's Manual (OM110000019A)
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The input circuit of an external signal is shown below.
1. TTL Level Input Terminal
ExTrg_1
ExTrg_2
GP_IN1
IN_RES1
4.7K
Ω
+5V
Extension connector CN6
Internal
circuit
74LCX14 equivalent
Figure6-12: TTL input terminal
Don't apply the voltage 5V to a TTL terminal.
Since a TTL signal tends to be affected by the influence of transmission
length or a peripheral noise,
Under the environment which a noise generates, use of a differential signal
(RS422) is recommended strongly.
When you use external trigger
Input the "L" level stabilized more than the period of at least 25 uS(s).
■
The setting example for software
The sample code for using TTL signal is as follows.
In this example, External trigger mode is set as continuation external trigger mode
(CC signal is outputted whenever it detects external trigger.)
<Sample code>
// Configure to use TTL signal
AcapSetInfo(hDev, INPUT_CH, ACL_EXT_EN, -1, 1);
// Continuation external trigger mode
AcapSetInfo(hDev, INPUT_CH, ACL_EXT_MODE, -1, 0);
// Reflect setting
AcapReflectParam(hDev, INPUT_CH)