ADLINK ACL-8454/12 - Manual (Page 29)

Installation & Configurations • 21
COUT12 IRQ 3 5 6 7 9
JP2
IRQ 10 11 12 15 X
JP1
/COUT6
JP3
High IRQ Level
Low IRQ Level
Ext.Int.
(ECLK10)
Figure 2.15 Block diagram of interrupt system
The default setting of the high and the low IRQ levels come from /COUT6
and ECLK10 respectively. The interrupt system on ACL-8454 is very
flexible to use. No matter under any system configuration, it is possible to
generate interrupt internally or externally.
In fact, when chip #4 are not installed, the COUT12 are floating and its
corresponding pin in the connector can be used as digital input pin or
external interrupt source. Whenever 8254 chip #4 is installed, it is an
internal interrupt source, otherwise, it is used as an external clock source or
just a digital input signal. The following table lists the combinations of the
interrupt sources. The label ‘I’ means ‘internal’ source and the label ‘e’
means ‘external’ source. The label ‘DI’ means the signal can be used as
digital input pin dedicatedly.
Chip
#1
Chip
#2
Chip
#3
Chip
#4
/COUT6 COUT12 ECLK10 Remarks
1 √ √ Ч Ч i e DI ACL-8454 / 6
2 √ √ √ √ i i e ACL-8454 / 12
3 √ √ √ × i e DI user installed
4 √ √ × √ i i e user installed
Table 2.6 Chips installation and interrupt sources
When 2 default chips (#1 and #2) are installed on ACL-8454, /COUT6 is
internal but COUT12 can be used as external interrupt source. ECK10 is
still used as digital input pin. If user installs the chip #3 by yourself, the
interrupt sources are in the same configuration as condition 1.
When all 4 chips are installed, /COUT6, COUT12 are internal interrupt
sources, only ECLK10 can be used as external. If user installs the chip #4
by yourself, the interrupt sources are the same configuration as condition 2.
2.13 Digital Input and Output