Current Server Time: 12:24 (Central Europe)

#apertus IRC Channel Logs

2019/12/11

Timezone: UTC


00:12
comradekingu
Bertl: "EvilDragon: comradekingu: Yeah those will be available once everything is fixed."
00:13
Bertl
great! so once that has happened, contact us again!
00:19
comradekingu
Will do, the current discussion of picking through the hardware/software bugs and making everything work is the "everything is fixed part"
00:20
Bertl
perfect! thanks!
00:21
comradekingu
Will do. Could be good enough for magic lantern now maybe :)
01:22
aombk
left the channel
01:22
aombk
joined the channel
01:27
aombk
left the channel
02:03
Bertl
off to bed now ... have a good one everyone!
02:03
Bertl
changed nick to: Bertl_zZ
05:50
Guest99
joined the channel
06:40
Guest99
left the channel
06:46
BAndiT1983|away
changed nick to: BAndiT1983
06:48
BAndiT1983
changed nick to: BAndiT1983|away
06:56
BAndiT1983|away
changed nick to: BAndiT1983
06:59
BAndiT1983
changed nick to: BAndiT1983|away
08:06
Bertl_zZ
changed nick to: Bertl_oO
11:52
RexOrCine|away
changed nick to: RexOrCine
12:00
RexOrCine
(12:52:03) anuejn: 17:03:44> screenshot is https://files.niemo.de/Screenshot_2019-12-09%20AXIOM-web.png < Nice.
12:14
Bertl_oO
changed nick to: Bertl
14:46
BAndiT1983|away
changed nick to: BAndiT1983
15:31
BAndiT1983
changed nick to: BAndiT1983|away
16:06
sebix
left the channel
16:28
BAndiT1983|away
changed nick to: BAndiT1983
16:37
Bertl
off for now ... bbl
16:38
Bertl
changed nick to: Bertl_oO
18:07
BAndiT1983
changed nick to: BAndiT1983|away
19:44
illwieckz
left the channel
19:58
illwieckz
joined the channel
20:17
BAndiT1983|away
changed nick to: BAndiT1983
21:08
RexOrCine
changed nick to: RexOrCine|away
21:21
anuejn
Bertl_oO: do you know of the top of your head what the clock applied to the temperature sensor of the cmv is in the current gateware?
21:22
anuejn
or how it is set if it is dynamically configurable
21:24
anuejn
and is there any mechanism to use an external frame trigger from the fpga to achive a constant frame rate that is independent of the exposure time?
21:25
anuejn
and how does one configure that?
21:40
Bertl_oO
whoa, slow down ... clock to the temp sensor?
21:40
illwieckz
left the channel
21:43
Bertl_oO
for the external frame trigger part, we have T_EXP1 and T_EXP2 connected on the SFE and routed via the IFB
21:44
Bertl_oO
so you can do custom exposures
21:44
Bertl_oO
but for the constant frame rate part, the current setup is basically enough
21:45
Bertl_oO
i.e. new exposures are triggered from the sequencer, which is kind of locked to the HDMI output
21:47
vup
Bertl_oO: the cmv12k has a extra input for a clock for the temp sensor: CLK_IN
21:50
Bertl_oO
well, CLK_IN is the master clock of the sensor
21:50
Bertl_oO
and yes, it is also used for the temp sensor
21:50
vup
well the datasheet says: "Optional input clock, frequency range between 10 MHz and 60 MHz. Only needed for the internal temperature sensor."
21:50
vup
so it seems it is only used for the temp sensor ;)
21:51
Bertl_oO
interesting
21:52
Bertl_oO
Input clock, frequency range between 5 and 60
21:52
Bertl_oO
MHz. Usually set to the LVDS input clock divided by
21:52
Bertl_oO
the bitmode. Used also for the temperature sensor.
21:52
Bertl_oO
that's what the data sheet up to 2.10 contained :)
21:53
vup
interesting,
21:53
vup
i am looking at the datasheet currently linked on the ams website
21:53
vup
which confusingly is called v1-00
21:54
vup
and from 2019-Feb-14
21:55
vup
so currently it is set to (250 / 12) MHz, right?
21:56
Bertl_oO
for the firmwares using 250 MHz LVDS clock, yes
21:56
Bertl_oO
s/firmware/gateware/
21:58
vup
right ok
21:58
Bertl_oO
there is an internal PLL which IMHO is based on the CLK_IN
21:58
Bertl_oO
but the use was discouraged because of ES01
21:59
Bertl_oO
The CMV12000 v2 has an internal PLL which could provide a fast internal clock by inputting a slower CMOS clock at
21:59
Bertl_oO
CLK_IN.
22:00
Bertl_oO
problems/errors with the PLL led to:
22:00
Bertl_oO
Therefore we recommend to only use the LVDS input clock and disable the internal PLL.
22:00
Bertl_oO
which might explain why the newer datasheets only use CLK_IN for the temp sensor
22:10
vup
yeah, seems like they removed the section on the PLL in version 2.10 and then changed the description of CLK_IN after that
22:10
vup
only the PLL supply is still left
22:12
Bertl_oO
wonder if that is required when the PLL is disabled :)
22:14
vup
yeah me too
22:14
vup
well it says "PLL 1.98 V supply (unused)" in the new datasheet
22:14
vup
so probably not
22:16
anuejn
lol
22:17
anuejn
what is sfe and what is ifb?
22:17
anuejn
thanks for the answers btw :)
22:17
Bertl_oO
Sensor Frontend and Interface Board
22:20
anuejn
ah
22:20
anuejn
ok
22:21
anuejn
that makes sense
22:21
anuejn
and the current gateware triggers the exposures syncronized with the hdmi
22:21
Bertl_oO
indirectly via the sequencer
22:21
anuejn
...where the refresh rate is baked into the bitstream?
22:22
Bertl_oO
nope, depends on your settings
22:22
anuejn
ah nice
22:22
Bertl_oO
e.g. if exposure and transfer takes 5ms
22:22
Bertl_oO
and the HDMI frame rate is configured to one frame every 6ms
22:23
Bertl_oO
(just making up numbers here :)
22:23
Bertl_oO
then the resulting sensor frame rate will be 6ms
22:23
anuejn
yup i see
22:23
anuejn
but how can the hdmi frame rate be configured?
22:28
Bertl_oO
to some extend via the FPGA registers
22:30
Bertl_oO
for example, 50FPS vs 60FPS does not depend on the actual HDMI clock rate
22:33
anuejn
but the hdmi clock rate is baked into the bitstream?
22:33
Bertl_oO
yes and no
22:33
BAndiT1983
changed nick to: BAndiT1983|away
22:33
Bertl_oO
the PLL/MMCM is pre-configured
22:34
Bertl_oO
but it is also mapped via registers, so you can adjust it
22:34
anuejn
ah nice
22:34
anuejn
i guess i will figure that out some other day (TM)
22:34
Bertl_oO
hehe
22:45
illwieckz
joined the channel