The QNET Data Acquisition (DAQ) Board serves one specific purpose in out experiment: to count muon coincidences.
1) PM Tube Input Channels: Where the photomultiplier tubes (PMT’s) are connected.
2) Trigger Output: The device that allows how many channels need to be active when performing experiments. This determination is done by programming it through the Hyperterminal (please see the commands page for more information).
3) Time-to-Digital Converter (TDC): Measure the arrival time of leading and trailing edges of coincidences, and keep track of their state at 75ns intervals.
4) CPLD (Programmable Fast Logic, AKA Complex Programmable Logic Device): Any programming, especially the trigger, is set using this chip.
5)
6) “Reset Everything” Switch: By pressing this button, any parameters that have been made will be reset to their default settings (command equivalent: RE. Please see the commands page for more information)
7) 5V Power Connecter: Connect a power source that has to be at least 5V and can be no more than 9V.
8) Microcontroller (MCU): Slows down the logic data to microseconds (instead of nanoseconds) so it can be read through a terminal on a PC.
9) “Reset Counter” Switch: By pressing this button, the number on the digital counter will automatically reset to zero. It will not reset any saved settings.
10) Digital Counter: This digital LED display counts how many coincidences, noise or singles were detected at the time under its current settings.
Setup
Manual Setup:
1) Connect a serial cable to the computer and the serial port of the QNET board.
Connect power. Once the power is connected, the digital counter should light up and automatically start counting very rapidly. The high amount of counts are also known as singles rates.
1) Open up Hyperterminal (if using Windows. If not, please refer to Appendix C in the QNET manual. On Windows:
a. Start
b. Programs
c. Accessories
d. Communications
e. Hyperterminal
2) The Hyperterminal window and a smaller window labeled “Connection Description” will appear. In the text box under “Name:”, please type in a name for this test. Click “OK”.
3) Another small box will titled “Connect To” will appear. Select the proper port in the “Connect Using” drop-down menu. Click “OK”
4) A larger box will appear titled “(insert port name) Properties”. Change the drop-down menus to the following settings:
a. Bits per second (Baud Rate): 19200
b. Data Bits: 8
c. Parity: none
d. Stop Bits: 1
e. Flow Control: Xon/Xoff
Then click “OK”
5) Type in whatever commands are needed to perform the specific tasks of your experiment (see the Commands section for a list of usable commands). For this particular experiment, use these commands:
a. RE
b. CE
c. DC
d. WC 00 13
e. DS
Commands (Also refer to the QNET Manual for more information)
BA- Display Barometer (when device is connected)
CE- Enable counters
CD- Disable counters
DC- Display counters
DF- Display Scalar Fifo Data (first 12 bytes as three 32-bit numbers)
DG-
Display
DS- Display Scalars (AKA display channel status and number of counts)
DT- Display time control registers of TMC, addresses 0-3
FL- Load Binary File
FR- Read SumCheck
FC- Copy to CPLD
GP-
Init link with
HF- Trigger Format
HS- Status Format
FC- Barometer Format (when device is connected)
NA
n- NMEA
NM
n- NMEA
RB- Resets TMC & CPLD on the board
RE- Reset MSP430 & TMC & CPLD (AKA Reset Everything)
SA n- Save TMC & CPD Registers to Flash
SA 1- Restore Default Settings
SB
n- Set Baud Rate (PC Link)
1= 19200
2= 38400
3= 57600
4= 11500
SN nnn- Serial Number (BCD)
SN- Display Serial Number
SN nnn- Store Serial Number
ST n- Send Status Data (n= =10n), (n!=1off), (see HF)
TH- Display Thermometer Data: -40 to 99°C (when device is connected)
WC mm nn- Write Counter Control Registers CPLD Address mm with data nn
WT mm nn- Write Control Registers TMC Address mm with data nn
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