ADLINK ACL-8454/12 - Manual (Page 15)

Installation & Configurations • 7
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 inserted 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.