Canon CXDI-55C, Service Manual

Page: 44 / 186

2. Installation
28
7.3.2 Signal Names and Functions in the Connection with the X-ray Generator
<X-ray Sync Signal>
Signal name Functions
RX_REQ
X-ray exposure signal
Indicates that an X-ray exposure is ordered at the X-ray generator side.
This signal needs to be retained at least for
T
PREP
period.
X-ray release signal (RX_COM) is not output if the T
PREP
is less than the necessary
period. It takes about 1 second in the worst case scenario before the operation can be
resumed when RX_REQ is negated in this period.
Time required to assert RX_COM after receiving the RX_REQ from the X-ray
generator
T
PREP
....................................................................... min.0 max.300ms
Since a captured image is read from the sensor when RX_REQ is negated (or RX_COM
is time out) as a trigger, reading action is delayed if RX_COM does not negate and time
out is used as the trigger, resulting in delay of image display timing.
We recommend using a configuration in which RX_REQ is negated.
Time required from X-ray exposure completion to negating RX_REQ
T
RX_REQ_NEG
............................................................ min.0 max.100ms
* Image display timing is delayed if this is not fulfilled.
RX_COM
X-ray release signal
Checks whether or not imaging is ready at the CXDI side after receiving X-ray exposure
signal (RX_REQ) from the X-ray generator. This signal is output to the X-ray generator
side when imaging is ready.
Time required from asserting RX_COM to exposing X-ray
T
PRE_DELAY
.............................................................. min.0 max.100ms
* Available imaging time is reduced if this is not fulfilled.
Time required to stop X-ray exposure after RX_COM halts
T
POST_DELAY
............................................................ min.0 max.100ms
* Problems such as shading could occur on images if this is not fulfilled.