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  1. viktor_kovacs

    Powered Up - A tear down...

    Imho the standard 20 mA white leds usually have a forward voltage of somewhere around 3.3V, so (9V - 3.3V) / 510 ohm = 0.011176 A ~ 11 mA. I've compared the brightness of two unmodified ones and they are much brighter than the latest PF ones, which are brighter than the previous PF variant and way brighter than the 1st run warm whites. (so far i've seen 3 PF led board variants, the original 1st run warm whites, the newer cold whites with the brighter green PCB and the latest darker green PCB with a modified component layout and higher brightness) The PU ones outshine all of the PF ones. On the other hand, is there a way to take these PU leds apart and assemble them without visibly damaging the circuit housing in the process? For the PF ones, it was relatively easy to take apart, mod for polarity and reassemble (take off diode bridge, bridge it with solder and reverse one led wire). Edit: i've scribbled over the picture above my polarity converson idea:
  2. viktor_kovacs

    Powered Up - A tear down...

    Unfortunately no as the already existing PF extension cable then could be connected on top and the other end of that to the 9V battery i mentioned. This setup would even allow reverse powering drained non rechargable batteries, which is a fire hazard. The overcurrent protection in the old battery boxes might protect the driving HUB, but the batteries would still get damaged. There is no clean solution for this as long as there is a pathway to an old 9V part or the PF battery boxes are allowed. (see: the empty PF AA battery box hack for powering a PF receiver from old 9V power sources like the LEGO train transformer) These completly legal and no modification required hacks mean any kid could accidentally do them and then you have wrong polarity power going into a PF receiver (there is a shorting diode to save the receiver, but that causes a short on the input line) or charging some non rechargable batteries or just two HUBs shorting together their motor outputs. The new PU system fixes these holes but this also means LEGO had to get rid of any compatiblity. This, in theory allows the PU system to be used by much younger kids without any danger of miswiring something. The inclusion of PU in the Duplo range is imho a good example. ps: In theory it would be possible to make an app controlled Duplo locomotive or even a programmable app controlled one... :-)
  3. viktor_kovacs

    Powered Up - A tear down...

    Actually the 6 wire cables are standard sized, so you can either use a 3x2 standard raster pin IDC plug, mostly found in computers and other digital circuits as the socket fits nicely into raster boards and could even be added in the middle of the cable (parallel ata sytle) or if's possible to use any 6 or more wires registered jack crimp plugs if you split the ends of the wire so they could feed into the new plug. The modified 6 pin RJ plug is used by NXT/EV3. In the latter case, be careful as the protocols as not compatible, so don't mix the two systems without proper converter circuits. Also shorting or higher voltage feedback on the 3.3V lead of the PU wires could very easily damage the HUBS and the sensor circuits in the smart accessories. (pretty much how more than 5V would kill most USB devices) Speaking of conveters, one of the LEGO Q&A blog pages state that the PF and PU protocols are not compatible but the PU and 9V outputs are, mostly because how the 9V high current line was swapped for a 3.3V low current one. Fortunatley the motor connections are the same, so it's possible to create a PU to 9V converter cable or a PU to PF output only cable, but this happening is not too likely as it would require a new dedicated ID from LEGO and would still run the possiblity of a 9V or PF output feeding into the motor outputs of the HUBs, creating an instant short between the two outputs or worse burning the protection diodes of the HUB's H bridge if the HUB is powered down. The use of exension cables was one way to damage PF receivers or WeDo1s. (one way is to use two extension wires to attach two sensors to the same port or to feed reverse direction switched power from a 9V battery box into the output of a PF receiver, both are very easy to do accidentially without any modified parts) Personally i think a straight extension cable from lego would be great for those who would like to hack around or just want to build larger MOCs and it would not cause any problems in the PU system. The not enough outputs problem could be solved by LEGO by making HUBs with more ports or by using more than one HUB in a MOC. ps: I also think the 12V system was the most hack-able without custom parts of modifying LEGO components but it was really hard for the kids (and sometimes even for their parents) to set up a working train layout or anything more than a basic loop. The current PU system makes if harder to miswire and damage the components than the PF system and at the same time makes it easier for kids to assemble everything alone as currently there is no way to connect anything the wrong way.
  4. I would like to add a few remarks: -the Boost motor has an encoder, so it's usable as a servo like in the NXT series, but there are no absolute positions, so the startup position will be treated as zero (this is why the robot should have its head centered upon hub boot) -the drive of the train motor seems to be speed regulating, so the train doesn't seem to visibly slow down in curves at lower speed settings even when heavily loaded (classic backemf regulation used by many DCC decoders have one small problem, only one motor could be connected to an output) -the Batmobile M motor has no encoder, but could be speed controlled with the right software (the current 2 port hub just defaults to on-off-on with the remote connected) -you can switch channels on the remote on the fly by pressing the center button, so it's possible to control up to 5 hubs on each 5 colors at the same time (this allows using up to 10 independent channels with a single remote and 34 AAA batteries)
  5. viktor_kovacs

    Powered Up - A tear down...

    The sign of a smart accessory is that the ID lines are not fixed to anywhere. There is a small imho AD chip for each port in the HUB to detect this. If they are not fixed, the HUB sends a query command to the accessory (smart motor/sensor) every now and then and it reports back its info in a response packet. This allows on the fly plug and play detection and the type info and actual values could be requested in one message. So far all high current output driving is done on the two motor output pins as there are no other high voltage and high current outputs on the connector. The 4 other pins are for signal ground, 3.3V logic power and the ID-s. This, in theory would allow a smart, but battery and radioless hub to be added (kind of like a distribution strip) that has a microcontroller and reports back to the main hub. Then the main hub could query the ID-s or info packets of each connected accessory, while driving them with the same output signal. This would require an upgrade to the current protocol and new software for the HUB-s and the remote controller. Sadly without having a way to drive the motor inputs of each accessory differently based on its type, this would break the current beaviour of the PU system. Doable, but adding extra fully featured hubs or even an up to 16 port one would be much easier and probably much cheaper for LEGO. Using a dedicated HUB for every 2 or 4 outputs is imho a simple way to get around the output current limitations of AAA batteries and avoid the software complexities that come with a tree structure. Imho a 4 port hub with AA batteries is possible and seems logical for larger technic builds, but LEGO could as well just use two 2 port hubs and have the same end result.
  6. viktor_kovacs

    Powered Up - A tear down...

    With a bit of help from Ashi, i did some testing with a full locomotive setup with two hubs, two train motors (one reversed), two led pairs and a remote on a full layout. It works, but the usable range is rather low. The remote starts giving end of range blinks only after about 10 meters and looses connectivity at around 15. All this with two hubs on the same channel and straight line of sight between the hubs and the remote. Having an active bluetooth connection from someone's phone to a few nearby sbricks could get the reliable connection distances down to about 5 meters, with the disconnection distance not really affected. Having only a single hub connected increased the maximal distance to about 4/3 of the dual case. This is regardless of having them on the same color and together or on different colors and a few dozen cm-s apart. I probably did something wrong as both the 12 eneloop and the 12 white ikea rechargable AAA batteries got drained after around two hours to 6V (1V per cell), this is when the hubs turn off. The same type of AA ikea batteries last around 6 hours in the same class of locomotive with a PF battery box, a single PF receiver and two PF train motors and set to run at a medium speed while continously looping around (i speed matched the two trains). 2 hours seems very little from 12 AAA batteries with a single 8 wide locomotive and two relatively light 56 stud long ic coaches. On the other hand, power and top speed is roughly the same as for the PF train motors, we measured ~156 scale km/h top for these 1:42 trains with the standard sized train wheels on straight and level plastic track. This seems to be good enough for most trains. Bugs: Connection loss sometimes resulted in the secondary hub (that is connecting up second) not syncing back up when i moved closer and one time it lost plug and play support and detected both the leds and the train motor as on-off-on (medium) motors. I could only reset it by removing the battery for a second. The test train is the one with the headlights on:
  7. viktor_kovacs

    Powered Up - A tear down...

    Just a quick remark, it looks like 3x2 pin IDC connectors might fit the PU ribbon cables. These are small 6 pin variants of the old PATA connectors and you can even fit many of them on a single cable. This could allow a rasterboard compatible non lego connector to be added while keeping the PU plug on the end. Then a small circut board could be added as a passive distribution box to connect for example two train motors and multiple led lights to a single HUB port. As long as only pins 1 and pins 2 are connected on the board and the same type of passive part is connected to it (like train motors * 2 or led lights *2-8) it should work. Intelligent parts, like servos and sensors will not work. The strip could have diodes and other parts to make the added leds intelligent, like lighting up only with one polarity. Plugging in more than one PU plug from this paralleled bunch will probably kill both HUBs or both ports on the same HUB though, so it's not a safe hack, but at least allow the same basic functionality what PF v1 had with the stackable connectors. (including the clever way to fry an IR receiver, a WEDO 1 or the WEDO sensors by using some extension cables wrong) On the other hand, a PU socket using distribution strip connecting only the first four pins would be neat. (with the 1st socket as full passthrough for the IDs to work) ps: Took apart a PU HUB without desoldering anything, the circuit just slides out if you push in the battery tabs. The motor driver double H bridge is on the bottom. It's an LB1836, a nice big chip, but really good for only one motor per output. For two train motors, using both outputs or more than one HUB is a good idea.
  8. viktor_kovacs

    Powered Up - A tear down...

    A bit more hacking, this time the new Powered Up M motor (or what it's called). I changed the ID of the motor to the train motor by disconnecting the absolutely tiny 2.2k pulldown resistor in the middle just north of the number 4 (i just turned it out of the way, didn't fully remove it) and bridging pins 4 and 5. A bit of extra info about the pins first: -pin 1: motor 1 -pin 2: motor 2 -pin 3: ground -pin 4: 3.3V logic power -pin 5: id1 -pin 6: id2 And the ID pin connections for what i gathered from various forums: -train motor: id1 to 3.3V, id2 to ground -medium motor: id1 2.2k to ground, id2 to ground -leds (unchecked): id1 2.2k to ground, id2 unconnected These hacks are not that nice, but allow modified (useful) operation without hacking the software of the hubs or the remote or using a phone or other computer to control the hubs. Also they are easily doable and look pretty much reversible.
  9. viktor_kovacs

    2018 Lego Trains

    I've checked the SATA cable connection and the plug with its top removed aligns perfectly, including the small cutout on one side that matches the LEGO plug. The 7th connector on the other side of the SATA plug has to be cut out for the other side of the Powered Up plug. Without the top of the SATA plug, the holding power is zero, so something has to be glued on top with the right spacing to create a crude wired Powered Up socket. It's not too reliable as the side bumps in the LEGO Powered Up socket that are used to hold the plugs in are missing from this hack. It's good for testing but i woudn't use it in a moc. The spacing and the side notch certainly looks like Lego was inspired by both the SATA connector and the standard registered jacks for the Powered Up connector. The 3.3V power in the plug means there is no constant battery power on the wires for a repeater or a passive hub. Personally i'm trying to figure out a Lego only solution (with a bit of modding, but no external parts) to have up to 3 lights on a single output as usually 2 motors and 5 lights are what i use in my current train mocs (both 9V and PF), which gives 3 white + 2 red on both ends of a locomotive (with direction modded PF leds and colored lenses). The current dual motor/dual hub setup i tested only allows two led pairs on the unused ports. The good part is that the two hubs could be on two opposing ends of a longer train, so great for articulated railcars or longer sets with power on the ends (like a flirt, desiro, tgv/horizon express or the Florida brightline train in the new 60197 set)
  10. viktor_kovacs

    Powered Up - A tear down...

    Just a bit of info and a quick video for those who are looking for a simple way to motorize a train with powered up and two train motors. You can reverse one of the motors (the howto is here:, then connect two hubs to the same controller using the same output on both. This will have the same effect as using a single power functions receiver and a polarity switch on one of the motors. The two other outputs remain free for connecting two pu leds or any other extra function. ps: I think the speed control bug mentioned above is based on the motor type detection and if the motor is plugged in during startup and the order of startup for the hubs, which means modifying the wiring of the two id pins could allow to mod a train motor to be a two speed hold to run and the non feedback pu motor to be speed controllable like the train motor. I'll try to test this and the leds for adding polarity based control as soon as i get some.