SIS Documentation
SIS3820
VME Scaler
Page 26 of 79
7.5 (0x10)Acquisition preset register
#define SIS3820_ACQUISITION_PRESET
0x10 /* read/write; D32 */
This read/write register allows you to define the number of counting periods to acquire in
MCS mode. The preset value is 32-bit wide. A preset value of 0 results in continuous MCS
operation.
Further LNEs are ignored after completion of acquisition until a key reset acquisition VME
access is performed. The completion flag is cleared upon reset acquisition also.
Bit Function
31
bit 31 of preset value
... ...
0
bit 0 of preset value
•
The register can be used in scaler mode also
•
it is not associated with a direct interrupt. Interrupt generation can be accomplished in
conjunction with the “acquisition completed (IRQ source 2, edge sensitive)
•
The status flag of the active mode (scaler enabled e.g.) will be cleared upon completion
7.6 Acquisition count register (0x14)
#define SIS3820_ACQUISITION_COUNT
0x14 /* read D32 */
This 32-bit wide read only register holds the number of acquisitions. It is cleared with the
start operation and incremented with consecutive LNE pulses. The contents of the acquisition
count register is compared with the contents of the acquisition preset register if the later is non
zero. Acquisition is completed as soon as the acquisition count is greater or equal than the
acquisition preset value.
Bit Function
31
bit 31 of acquisition count
... ...
0
bit 0 of acquisition count