Poll: How much would you be willing to pay for a Neo900 (complete device) with TI DM3730 1GHz/512M-RAM/1GB
Poll Options
How much would you be willing to pay for a Neo900 (complete device) with TI DM3730 1GHz/512M-RAM/1GB

Reply
Thread Tools
joerg_rw's Avatar
Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2761
maybe our tech affine community members want to contribute to a recent discussion Werner and I do about the HackerBus USB connection? Concerns are about mechanical stability of the 3pin header (Mill-Max 851-43-003-30-001000) as well as about signal integrity with a unterminated stub of >5mm length (from the header springs) on DP/DN. Alternatives we look into: Zebra strips (http://www.abatek.com/en/products/connectors.html) or pogopins on user's extension board (http://www.digikey.com/product-searc...4-11-0&stock=1)

/j
 

The Following 13 Users Say Thank You to joerg_rw For This Useful Post:
Feathers McGraw's Avatar
Posts: 654 | Thanked: 2,368 times | Joined on Jul 2014 @ UK
#2762
Jolla, take note... THIS is how you do openness!
 

The Following 9 Users Say Thank You to Feathers McGraw For This Useful Post:
joerg_rw's Avatar
Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2763
enyc contributed great inspiration (IRC) and Werner revisited pinmux and we plan to come up with a dedicated USB interface on HackerBus primary connector (2 GPIO_x function reassignment). The OTG USB will have landing zone pads for pogopins mounted on user circuit, instead of that 3-pin SMT connector. Our recommendation is to leave OTG alone and rather use the dedicated USB host interface on hackerbus, for sake of less conflicts with original purpose of the OTG interface
Comments solicited

[edit] revised HB main connector pin assignment:
Code:
VBAT_RAW | VBAT_RAW
USB_HB_DP|USB_HB_DM
         GND   |  GND      
  NFC_GND | NFC_ANT
         GND   |  GND 
VBUS_OTG | VBAT_SWITCHED
GPIO_d/3V3 | GPIO_c
      GPIO_b | GPIO_a
   UART_TX | UART_RX 
 UART_CTS | UART_RTS
/j

Last edited by joerg_rw; 2016-01-27 at 19:54.
 

The Following 11 Users Say Thank You to joerg_rw For This Useful Post:
Posts: 11 | Thanked: 50 times | Joined on Dec 2009
#2764
Originally Posted by wpwrak View Post
Great, thanks a lot !

I currently have my eyes set on the L130-5780002011001 with 5700 K and a minimum CRI of 80%. CRI is something new I found:
https://en.wikipedia.org/wiki/Color_rendering_index

Of course, two parameters are still a very course approximation of the actual spectrum. But you'd probably need serious lab equipment to determine that.
Is this flash color still an active issue? The comments are 2 months old.

I have both an original N900 and an x-rite i1Pro2 spectrophoto/radiometer. It should be able to read the flash color as detailed spectrum curve, and the dominant color in K.

Is there still interest in this, particularily by the persons who select the flash components? Please give feedback here on the thread or by email in case that such a measurement is still useful at this point.
 

The Following 10 Users Say Thank You to jetmarc@hotmail.com For This Useful Post:
joerg_rw's Avatar
Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2765
Originally Posted by jetmarc@hotmail.com View Post
Is there still interest in this, particularily by the persons who select the flash components?.
Yes, of course. Highly appreciated, many thanks for helping with this

/j
 

The Following 3 Users Say Thank You to joerg_rw For This Useful Post:
joerg_rw's Avatar
Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2766
http://neo900.org/stuff/joerg/4_BB-xM/
Thanks to xes for moderation!
Let's see if mouser actually can ship the ordered 6 board in 3 days - ordered a 20 months ago
 

The Following 9 Users Say Thank You to joerg_rw For This Useful Post:
Posts: 11 | Thanked: 50 times | Joined on Dec 2009
#2767
Originally Posted by joerg_rw View Post
Yes, of course. Highly appreciated, many thanks for helping with this

Ok I did this today, and this is what I got.

Target: My N900 was bought some 3-6 months after market introduction. The aparture of the camera/flash unit had a blue-colored tint on the edges, which was neutralized with black ink. To measure the flash color, I turned on the "flashlight" mode. I am not sure if this is a low current mode and if the current influences the color, but it is easier to measure. Let me know when this is not good enough.

Tools: x-Rite i1Pro2 and ArgyllCMS 1.8.3

Measurement 1: spotread -a -N

For this measurement I used the ambient light adapter and had the phone shining into the sensor from a distance of maybe 2 cm.

Code:
 Result is XYZ: 10381.329780 11168.856635 10074.093410, D50 Lab: 542.634253 -29.250888 -29.109195
 Ambient = 11168.9 Lux, CCT = 5675K (Delta E 9.687946)
 Suggested EV @ ISO100 for 11168.9 Lux incident light = 12.1
 Closest Planckian temperature = 5403K (Delta E 8.488890)
 Closest Daylight temperature  = 5517K (Delta E 4.974792)
 Color Rendering Index (Ra) = 70.1 [ R9 = -37.7 ]
 Television Lighting Consistency Index 2012 (Qa) = 48.5
Measurement 2: illumread -v -N

This measurement consists of 3 individual measurements. The first is of the flash shining directly into the sensor, and I used the a similar setup as before (ambient light adapter, approx 2 cm). The second measurement is reflected from paper, and I used vanilla office printer paper and an angle of 45 degrees approx. The third measurement is the paper color itself, and I use the normal spot reading setup. The last two measurements are supposed to clue about the UV contents of the light source.

Code:
SPECT  

DESCRIPTOR "Argyll Spectral power/reflectance information"
ORIGINATOR "Argyll CMS"
CREATED "Sun Mar  6 02:25:02 2016"
SPECTRAL_BANDS "45"
SPECTRAL_START_NM "290.000000"
SPECTRAL_END_NM "730.000000"
SPECTRAL_NORM "1.000000"

NUMBER_OF_FIELDS 45
BEGIN_DATA_FORMAT
SPEC_290 SPEC_300 SPEC_310 SPEC_320 SPEC_330 SPEC_340 SPEC_350 SPEC_360 SPEC_370 SPEC_380 SPEC_390 SPEC_400 SPEC_410 SPEC_420 SPEC_430 SPEC_440 SPEC_450 SPEC_460 SPEC_470 SPEC_480 SPEC_490 SPEC_500 SPEC_510 SPEC_520 SPEC_530 SPEC_540 SPEC_550 SPEC_560 SPEC_570 SPEC_580 SPEC_590 SPEC_600 SPEC_610 SPEC_620 SPEC_630 SPEC_640 SPEC_650 SPEC_660 SPEC_670 SPEC_680 SPEC_690 SPEC_700 SPEC_710 SPEC_720 SPEC_730 
END_DATA_FORMAT

NUMBER_OF_SETS 1
BEGIN_DATA
0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00490145 0.00177026 0.00431980 0.0214035 0.145008 0.653737 2.039361 3.369266 1.993886 0.779962 0.403550 0.404197 0.686909 1.171644 1.634942 1.913347 2.028934 2.063459 2.059977 2.020874 1.931819 1.784170 1.599621 1.397492 1.196757 1.008129 0.835002 0.681009 0.547155 0.433853 0.336795 0.259777 0.201203 0.157002 0.124581 0.104186 
END_DATA
This file can be examined using specplot:

Code:
Type = File 'test2' spect 0 [Black]
XYZ = 0.931246 1.000000 0.900338, x,y = 0.328878 0.353159
D50 L*a*b* = 100.000000 -5.762902 -5.919376
CMYV density = -0.144735 -0.240183 -0.112879 -0.219696
CCT = 5650.126305, VCT = 5387.721842
CDT = 5651.454724, VDT = 5501.851749
CRI = 70.1 [ R9 = -37.0 ]
TLCI = 48.5
CIEDE2000 Delta E = 1.901252
The last command also creates a plot image: base64 -d > plot.png

Code: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Hopefully this helps for your project. I really liked the N900. To me it was a little laptop in my pocket, with SSH openvpn and rdesktop. Now I am on Android and I really miss these things. On Android, you can only do what you are supposed to do (much like on the N9, which ended the the drawer after just 2 days). Sometimes I still use the N900 as laptop replacement on short trips, and I wish someone would offer a modern device for developers.
 

The Following 14 Users Say Thank You to jetmarc@hotmail.com For This Useful Post:
joerg_rw's Avatar
Posts: 2,222 | Thanked: 12,651 times | Joined on Mar 2010 @ SOL 3
#2768
@jetmarc
Many thanks! This is extremely helpful.

re flashligt mode: yes that is with reduced LED current, the LEDs would burn out at full power used during flashing for longer than 1 or 2 seconds. It's also known that there been a greenish hue aberration in iirc macro mode before iirc PR1.2 drivers.

I guess the results from your test are good enough to determine which color binning we should use for the LEDs, however if it doesn't cause too much of a hassle to you, a short reference colortemp test with flash mode would be welcome - to extend the flash duration you should cover the cam lens.

Again many thanks
cheers
jOERG
 

The Following 4 Users Say Thank You to joerg_rw For This Useful Post:
Posts: 79 | Thanked: 719 times | Joined on May 2014 @ Buenos Aires, Argentina
#2769
Originally Posted by jetmarc@hotmail.com View Post
Ok I did this today, and this is what I got.
Thanks a lot, this is great data ! A question about interpreting the color temperatures:

Code:
 Ambient = 11168.9 Lux, CCT = 5675K (Delta E 9.687946)
 Closest Planckian temperature = 5403K (Delta E 8.488890)
 Closest Daylight temperature  = 5517K (Delta E 4.974792)
I realize that there is a lot to know about light that I didn't even know I didn't know ;-) Of these three, would "CCT" (approx. 5700 K) be the one that corresponds to the CCT parameter of the LED ?

In the L130 series, we get to choose between nominal CCT values of 5000 K and 5700 K (or values further out). Each also comes with fairly large tolerances, e.g., 5500 K would still seem to be within the "best" tolerance bin of the nominally 5700 K LED.

The color binning is shown in figure 16 of
http://www.lumileds.com/uploads/461/DS209-pdf

Code:
 Color Rendering Index (Ra) = 70.1 [ R9 = -37.7 ]
I'm very happy about this one. I had been a bit worried about the CRI, since the best we can get at 5700 K is 80%, and I wasn't sure if the "missing" 20% would be a problem. But this is actually even one step better than the original then.

Code:
The last command also creates a plot image: base64 -d > plot.png
Thanks a lot ! The curve does indeed look like the 5700 K curve of the L130.

Again, thanks a lot ! It's always better to have solid data to rely on than guesswork, no matter how sophisticated.

- Werner
 

The Following 7 Users Say Thank You to wpwrak For This Useful Post:
Posts: 79 | Thanked: 719 times | Joined on May 2014 @ Buenos Aires, Argentina
#2770
Originally Posted by joerg_rw View Post
a short reference colortemp test with flash mode would be welcome
I did a quick search for material supporting that LED current would directly affect color, but didn't find anything. However, I did find that junction temperature has a significant effect on color:

The short version:
http://www.lrc.rpi.edu/programs/NLPI...s/LED/heat.asp

A much longer analysis:
http://www.digikey.com/en/articles/t...er-pwm-dimming

Alas, the data sheet only shows (figure 3) that the LED gets less bright when hotter, but doesn't mention any effect on color.

In any case, the L130 specification is based on a steady state with the junction temperature held at 25 C. Measurements that do not control the junction temperature should therefore read a little higher, but given the low torch current of only 50 mA [1], I wouldn't expect a significant deviation. Thus, the measurement results should be more than sufficient for the purpose of component selection.

- Werner

[1] https://wiki.maemo.org/N900_Hardware_Flash_Torch
 

The Following 6 Users Say Thank You to wpwrak For This Useful Post:
Reply

Tags
neo900, thank you!

Thread Tools

 
Forum Jump


All times are GMT. The time now is 16:10.