SIS Documentation
SIS3820
VME Scaler
Page 23 of 79
7.4 Interrupt Control/Status register (0xC)
#define SIS3820_IRQ_CONTROL
0xC
/* read/write; D32 */
The interrupt sources are enabled with the interrupt control register. The interrupt source is
cleared in the interrupt service routine. The status internal IRQ flag can be used for tests
without activating VME interrupt generation. It is set whenever an interrupt would be
generated if interrupting would be enabled in the interrupt configuration register.
fourth condition is reserved for future use.
Bit Function
(w)
(r)
Default
31
1 Shot : IRQ_UPDATE
Status IRQ source 7 (reserved)
0
30
unused
Status IRQ source 6 (reserved)
0
29
unused
Status IRQ source 5 (reserved)
0
28
unused
Status IRQ source 4 (FIFO almost full)
0
27
unused
Status IRQ source 3 (overflow)
0
26
unused
Status IRQ source 2 (acquisition completed)
0
25
unused
Status IRQ source 1 (FIFO threshold)
0
24
unused
Status IRQ source 0 (LNE/clock shadow)
0
23
Clear IRQ source 7
Status flag source 7
0
22
Clear IRQ source 6
Status flag source 6
0
21
Clear IRQ source 5
Status flag source 5
0
20
Clear IRQ source 4
Status flag source 4
0
19
Clear IRQ source 3
Status flag source 3
0
18
Clear IRQ source 2
Status flag source 2
0
17
Clear IRQ source 1
Status flag source 1
0
16
Clear IRQ source 0
Status flag source 0
0
15
Disable IRQ source 7
Status VME IRQ
0
14
Disable IRQ source 6
Status internal IRQ
0
13
Disable IRQ source 5
0
0
12
Disable IRQ source 4
0
0
11
Disable IRQ source 3
0
0
10
Disable IRQ source 2
0
0
9
Disable IRQ source 1
0
0
8
Disable IRQ source 0
0
0
7
Enable IRQ source 7
Status enable source 7 (read as 1 if enabled, 0 if disabled)
0
6
Enable IRQ source 6
Status enable source 6 (read as 1 if enabled, 0 if disabled)
5
Enable IRQ source 5
Status enable source 5 (read as 1 if enabled, 0 if disabled)
0
4
Enable IRQ source 4
Status enable source 4 (read as 1 if enabled, 0 if disabled)
0
3
Enable IRQ source 3
Status enable source 3 (read as 1 if enabled, 0 if disabled)
0
2
Enable IRQ source 2
Status enable source 2 (read as 1 if enabled, 0 if disabled)
0
1
Enable IRQ source 1
Status enable source 1 (read as 1 if enabled, 0 if disabled)
0
0
Enable IRQ source 0
Status enable source 0 (read as 1 if enabled, 0 if disabled)
0
The power up default value reads 0x 00000000
Note:
The clear IRQ source bits are relevant for edge sensitive IRQs only