ADLINK Technology NuDAQ ACL-8454, Руководство пользователя

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Installation
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2.4 Default Configurations
To operate the ACL-8454 correctly, users should understand the
structure of ACL-8454 and details of the possible configurations.
The block diagram of the ACL-8454 is shown in chapter 1. It
contains the clock system, counter system, interrupt system and
address decoder etc. The following sections describe the details
and the default setting is list in Table 2.1.
Items Default Configuration Setting by:
Base Address 0x240 S1
Clock Source #1 2M Hz CLOCK1
Clock Source #2 100K Hz CLOCK2
8254 chips U1, U2 installed
U3, U4 not installed --
Clock Sources of Counters Internal Clock Source #1
(=2M Hz) CK n
Gate Sources of
Counter 1~4 External Gate G1 ~ G4
Interrupt Level #1 IRQ 15 JP1
Interrupt Level #2 No Connection JP2
Source of Interrupt Level #2 External Interrupt Sources JP3
Table 2.1 Default Configuration of ACL-8454
You can change the ACL-8454's default configuration by setting
jumpers and DIP switches on the card for your own applications. The
card's jumpers and switches are preset at the factory. A jumper
switch is closed (sometimes referred to as "shorted") with the plastic
cap in-serted over two pins of the jumper. A jumper is open with the
plastic cap inserted over one or no pin(s) of the jumper.
Before changing the default configuration, users must fully
understand the operation of the ACL-8454. The setting and the
basic operation theorem are discussed in this chapter. It is
recommended to refer chapter 3 for details of the registers and to
refer chapter 4 for application notes.