TDC-GP2 acam messelectronic gmbh, TDC-GP2 Datasheet - Page 21

• Manufacturer Part Number: TDC-GP2
• Description: Precision Time Interval Measurement
• Manufacturer: acam messelectronic gmbh

a. Un-calibrated data format:
16 Bit Signed integer in complements of 2. 1BIN =
uncalibrated gate delay 65ps.
Time
b. Calibrated data format:
32 Bit fixed-point number in complements of 2. Given in
multiples of the reference clock.
The measured time interval may not exceed
and will write the data 0xFFFFFFFF to the output
register.
The configuration of the ALU allows only one hit
calculation at the time. In case more than one hit has
been measured it is necessary to write new commands
to HIT1/HIT2 to instruct the ALU for calculating the
other hits. After writing to HIT1/HIT2 it is necessary to
wait for minimum 4.6µs (calibrated data) or 580ns (un-
calibrated data) before reading or writing again to
HIT1/HIT2.
2
Time
T
ref
RES
RES_X x 65ps
2
ClkHSDiv
_
acam-messelectronic gmbh - Am Hasenbiel 27 - D-76297 Stutensee-Blankenloch - Germany - www.acam.de
X
, otherwise the ALU will go into overflow
T
ref
N
, N = 1, 2 or 4
21
Example:
configuration
...
write reg1=0x104400
Hit1-Start
...
Initialize
...
while(Check interrupt flag)
write reg1=0x204400
wait(4.6µs)
write reg1=0x304400
wait(4.6µs)
write reg1=0x404400
wait(4.6µs)
Now all Hit data are available from registers 0 to 3.
The load pointer value is 4.
At the end the TDC-GP2 has to be initialized again to be
ready for the next measurement. This is done by send-
ing the opcode "Init" so that the TDC accepts new Start
and Stop hits.
'4 hits on channel 1, calculate
calculate Hit2-Start
calculate Hit3-Start
calculate Hit4-Start
3.2.1 Configuration
TDC-GP2