tag:blogger.com,1999:blog-8042569099194536366.post4533362254648010866..comments2024-03-28T12:48:59.344+00:00Comments on Captain Bodgit: BirdBoxPi2015: Jessie U-Turn & other troublesSteveDeehttp://www.blogger.com/profile/10645378028590228663noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-8042569099194536366.post-15307721299816840632015-02-05T21:48:21.010+00:002015-02-05T21:48:21.010+00:00IC1 is a ULN2003, which is a 16 pin chip with 7 dr...IC1 is a ULN2003, which is a 16 pin chip with 7 drivers. Each driver is 5V input compatible, and each output is "open collector" so you can connect something like a relay or lamp or (in my case) 3 leds. Its a great device for driving much heavier loads than the Pi will tolerate directly on its output pins. IC1a and IC1b are just 2 of these drivers.<br /><br />These drivers invert the input; so a HIGH at the input (3.3V from the Pi) switches the driver output LOW (0V..ish), which puts 12V across the led circuits. The brightness of the leds depends upon the current flowing through the leds.<br /><br />Yes, you could use PWM, but it would make the interface more complicated, and do you need such fine control of the lights? I found last year that just having 2 options (bright and dim) was all I needed. The dim option is adequate for running motion, and the bright option helps produce reasonable quality video when using RaspiVid.<br /><br />I hope that helps, but if in doubt, ask.SteveDeehttps://www.blogger.com/profile/10645378028590228663noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-51640866924477470732015-02-05T19:20:40.828+00:002015-02-05T19:20:40.828+00:00A noob question, but what is IC1a/b? I found some...A noob question, but what is IC1a/b? I found some websites suggesting that you could use the PWM pin to control brightness too?NestBoxTechhttps://www.blogger.com/profile/17596961979586589583noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-32868780214561875772015-02-04T09:19:09.815+00:002015-02-04T09:19:09.815+00:00Take a look at the circuit diagram in this post: h...Take a look at the circuit diagram in this post: http://captainbodgit.blogspot.co.uk/2015/01/birdbox2015-picaxe-controller-details.html<br /><br />When I select dim illumination, IC1a input is driven HIGH by the RPi gpio, so its output goes LOW and the leds are affectively connected across 12V with 690 Ohms (470 + 220) in series. (the question marks by these 2 resistor values is because I may change the values during final test).<br /><br />When I select bright illumination, IC1b input is driven HIGH by the RPi gpio, so its output goes LOW and the leds are affectively connected across 12V with 220 Ohms, giving a much higher current.<br /><br />You could modify this circuit slightly by putting resistors in the outputs of both IC1a & IC1b. That way you could have 4 modes/options:-<br />Both outputs off - no lights<br />IC1a output on - dim lights<br />IC1a off, IC1b on - medium lights<br />IC1a & IC1b on - max brightness<br /><br />I hope this helps. HOWEVER, don't use my resistor values, especially if you are using iR leds. Read this post if you don't already understand LEDs: http://captainbodgit.blogspot.co.uk/2013/11/dont-waste-power-with-leds.html<br />It will help you determine safe resistor values for you chosen led type (the led Vf varies, not only by colour, but for the same colour from different types).SteveDeehttps://www.blogger.com/profile/10645378028590228663noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-52992207246312972302015-02-03T18:40:54.698+00:002015-02-03T18:40:54.698+00:00How do you control the brightness of led in softwa...How do you control the brightness of led in software? Mine are just connected to GPIO output with a resistor in between, so are either on or off...NestBoxTechhttps://www.blogger.com/profile/17596961979586589583noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-65668387117433111662015-02-03T18:29:15.567+00:002015-02-03T18:29:15.567+00:00Yeah, finding time is the problem, but I think you...Yeah, finding time is the problem, but I think your new bird box should get priority over the trail cam, as this years box really needs to be deployed by the first week in March.<br /><br />I think I saw some posts on the forum about your filter switcher. That sounds amazing.<br /><br />I'm not using iR, as I was not happy with any of the potential robin nest sites around my garden. So this year I'll put last years 32mm hole box back where it was (but maybe at an angle, like yours, but not nearly as posh). And build a new box, probably with a 25mm hole, again attached to an archway at an angle.<br /><br />So the 3 leds I'm using (in both boxes) are super-bright white, pointed upwards so as not to dazzle the birds, with a white ceiling as a reflector. Once again I'll have two brightness options: nice but dim, and battery chicken mode. During the early days the system is triggered by activity which powers/boots the Pi, and once my program loads, Motion is started and the lights are typically turned on to dim mode (or however I left it since the last time an option was selected).<br /><br />I only really use the bright mode when there are chicks to film (using RaspiVid not Motion).SteveDeehttps://www.blogger.com/profile/10645378028590228663noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-81888956722265958942015-02-02T22:24:55.360+00:002015-02-02T22:24:55.360+00:00Progress is tantric... I've got the ir cut fil...Progress is tantric... I've got the ir cut filter working using L293D ic as polarity reversing switchy thing.. It's a question of getting all the parts that work separately working together and probably building a new enclosure. V little time at the moment. Also have mark II nest box for this spring to finish. My track record seems to be to build next years box this year, as last years box is beginning to get some interest... Get a daily blue tit visit to last years box. Out of interest, with your IR illumination, do you have it on all the time, or do you have it activated by some trigger? I've got an infrared beam split triggering a couple of white LEDs to come on,but don't know whether to keep them on for a period, or what....NestBoxTechhttps://www.blogger.com/profile/17596961979586589583noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-59782923327022377262015-02-02T21:09:21.539+00:002015-02-02T21:09:21.539+00:00I added a led to the second picture, but it wasn&#...I added a led to the second picture, but it wasn't actually soldered in.<br /><br />The current plan; I'm going to cut a wider camera perf board (replacing the one in the photos) so that when the module is attached to the box, it will sit over a rectangular aperture facing downwards. I'll fix 4 upward facing studs (probably M3) to the aperture, and have 4 holes in the bit of the camera perf board that sticks out either side, beyond the width of the other boards. That way I can easily fit nuts to the exposed studs.<br /><br />The 3 x 10mm leds (should arrive this week) will be fitted to the perf board and will face upwards..ish, and the perf board will be painted white to act as a reflector.<br /><br />How is progress with the Pi trail-cam?SteveDeehttps://www.blogger.com/profile/10645378028590228663noreply@blogger.comtag:blogger.com,1999:blog-8042569099194536366.post-75648094715032578612015-02-02T18:41:03.257+00:002015-02-02T18:41:03.257+00:00I like your new BirdCam Pi shield. I wouldn'...I like your new BirdCam Pi shield. I wouldn't worry about having the camera open to the inside of the box. I've a webcam that has been open for interference in a large box that is used regularly by squirrels without issue. My birdcam box has a piece of glass between the webcam and the pi - which is suffering from led reflection since the black enamel paint I painted over the webcam's led is too thin.<br /><br />Have you got any lighting in there - I cant see any leds on the underside of your perf board?NestBoxTechhttps://www.blogger.com/profile/17596961979586589583noreply@blogger.com