CAEN V775 TDC
| Address | |
| Pin | Setting |
| SW 1 | 1 |
| SW 2 | 6 |
| SW 3 | 0 |
| SW 4 | 8 |
initialize TDC
-> c775Init(0x610000) Initialized TDC ID 0 at address 0x90610000
Common Start/Stop =
BitSet 2 is used to set the TDC in common start or stop mode.
0 => common start 1 => common start
Use the Status function to see what the bit is set at
-> c775Status(0)
STATUS for TDC id 0 at base address 0x90610000
----------------------------------------------
Interrupts Disabled
Last Interrupt Count : 0
--1-- --2--
Status = 0x0050 0x0002
BitSet = 0x0000 0x0898
Control = 0x0000
FSR = 140 nsec
Event Count = (No Events Taken)
Last Event Read = (No Events Read)
value = 37 = 0x25 = '%'
BitSet 2 is set to 0x0898 = 100010011000 d
The above has bit 10 ( starting from 0 at the very left) set to 0 => common start
Read Data
Use PrintEvent to print out the data in the TDC to the ROC console
-> c775PrintEvent
TDC DATA for Module 0
Header: 0xfa000100 nWords = 1
0xf80048b8
Trailer: 0xfc00005a Event Count = 90
value = 3 = 0x3
Decoding the data
Header
Header = 0xfa000100 = 11111010000000000000000100000000 b
bits 27-31 contain the GEO address = 11111 d = 0xF bits 26-24 contain the type of word 010 => header bits 16-23 contain the crate number = 00000000 => crate 0 bits 8-13 contain the number of channels contained in the data word = 000001 = 1 TDC channel
Data Words
data = 0xf80048b8 = 11111000000000000100100010111000 b
bits 27-31 contain the GEO address = 11111 d = 0xF bits 26-24 contain the type of word 000 => dataum bits 16-20 contain the channel number = 00000 => channel 0 bit 14 = data valid bit = 1 => valid data bit 13 = underthreshold bit bit 12 = overflow bit 0 => ADC not in overflow bits 0-11 contain the TDC value = 100010111000