User Tools

Site Tools



This shows you the differences between two versions of the page.

Link to this comparison view

gca51-en [2018/11/12 08:56] (current)
Line 1: Line 1:
 +====== GCA51 2 x RFID + 8 input ports ======
 +[[english|{{ ​ rocrail-logo-35.png}}]]
 +[[english|Content]] -> [[hardware-en|Hardware]] -> [[hardware-en#​locoio|GCA]]
 +  *  [[mgv-overview-en|The GCA Modules]]
 +    * [[:​lnsv-en|Setup dialog]] | [[:​loconet:​lio-sw:​lio-sw|Setup protocol]]
 +{{ :​gca:​gca51_proto_pict08.gif?​200}}
 +^^^^By Peter Giling ^^^^
 +===== Description =====
 +Using the ID-12 or ID-20 RFID sensor, based on the idea of MERG, RFID in GCA units was first only possible with CAN-GC4, so for CBUS only.\\
 +Thanks to Rob, who opened the option to use it in RocNet as well.\\
 +But this ID-12 is a rather expensive solution, and also the used frequency of 125 kHz could be disturbed\\
 +too easy by the lokdecoder itself.\\
 +ID-12 together with one other sensor ID-20 were also pretty slow.\\
 +But for LNet there was no solution yet\\
 +Thanks to the large amount of time that several enthousiastic Railroaders invested in this matter, \\
 +the use of the much cheaper and better RC522 came in view.\\
 +Special thanks to Viktor, Robert, Liviu and last but not least Gerard, we thank them this very nice solution.\\
 +As mentioned before, this RFID solution is based on the RC522 sensor, which is widely available for a good price.\\
 +Also the transponder to be fixed in or under the locs and, eventually, also under the waggons and pullmans, is very cheap.\\
 +The unit as described here is made for LNet specially.\\
 +It is based on a Atgmega processor , and to make programming easy for almost anybody, without the need for\\
 +special programmers,​ the Atmel is traded for an Arduino Uno.\\
 +Now the Ardiono Nano, if bought by yourself, can be programmed using the on board USB connection.\\
 +There is no need here for special programming devices.\\
 +See below under firmware.\\
 +GCA51 contains two inputs for RC522 sensor, and 8 x input ports like it's standard brother GCA50.\\ ​
 +Also GCA51 has connections for standard RJ12 LNet connectors, as wel as GCA-LNet with the much more reliable SUB-D solution.\\
 +GCA51 can also be used for adapting between both connection options, but only for the LNet communication.\\
 +Supply is not transferred between RJ12 connectors and SUB-D connectors,​\\ ​
 +due to the rather strange situation that Railsync in LocoNet is used to supply the LocoNet modules,\\
 +Railsync itself is yet transferred.\\
 +Rocrail is 100 % ready for RFID, so now you have a perfect system, capable of indicating each moving part on your railroad separately.\\
 +The transponders are passive in a way, that they do not need any power, which makes it specially easy for waggons.\\
 +The unit is made to fit in standard LTD-01 box.\\
 +===== Supply =====
 +The board needs 5 V supply.
 +The total demand for the GCA51 when all I/O and RFID sensors are connected, exceeds easy 200- 300 mA.\\
 +This is a bit too much for a standard linear regulator like the good old 7805, since we have a supply form LocoNet or GCA LNet of 12V or even more.\\
 +It means that regulator should have a cooling for the 7 x 0,3 = 2,1 Watt.\\
 +Slowly the switching regulators are getting cheaper.\\
 +So the choice was now made to use a RECOM R-78E 5V type wich can easily handle 1 Amp, without any addional cooling at all.\\
 +This also means that the total consumption load from the LocoNet or GCA LNet supply is less than half, compared to a linear regulator.\\
 +But if you like to use the linear type with a cooling , it fits anyway and can replace the Recom.\\
 +The RC522 sensors need 3,3 V which is coming from the Arduino Nano unit.\\
 +  ​
 +GCA51 has two ways of connection:​\\
 +- via GCA-LNet D-connectors\\
 +- via standard RJ12 connectors.\\
 +In both situations the power is connected between the two connectors (Railsync + / - in case of RJ12)\\
 +Between D-Connector and RJ12, only Ground and LNet signal is passed through.\\
 +This is done to avoid any railsync problems.\\
 +High speed diodes D1,D2 and D3 take care of that.\\
 +===== Connection Hall sensors =====
 +Hall sensors can be connected directly to GCA51 connectors H1..H8.\\
 +Ports 9 to 16 are available for that, which are also used for interface boards like GCA93,​GCA94,​ GCA107 and many others.\\
 +The connection wires between Hallsensor and GCA51 can be up to approx 2 meters.\\
 +Please be careful not to feed those wires parallel with rails and rail wires.\\
 +If that is inevitable, keep a distance of 10cm  (approx 4''​).\\
 +Straight angle crossing is no problem.\\
 +A bit of twisting these wires (also the rail wires) will inprove protection to any distorsion.\\
 +Be sure to install RP1 and RP2 with a value of 4 x 470 Ohm each for best performance.\\
 +Below, a drawing is downloadable of how to connect hallsensors.\\
 +{{:​mgv:​hardware:​connection_tle4905.pdf|Connection TLE4905 hallsensor}}\\
 +===== Connection of driver boards =====
 +All driver boards for input and output like GCA76, GCA77, GCA93, GCA94, GCA107, GCA173 ​ etc, can all be used to connect to J1.\\
 +Programming of the these I/O ports can be done in Rocrail using menue'​s Programming > GCA > GCA50\\
 +Ports 9 to 16 are available for that, which are also used for hall-senor connection\\
 +Up until now, only pulse outputs are not supported.\\
 +Maybe in the short future, that will also be available.\\ ​
 +We are still looking for somebody to take up that programming task.\\
 +===== Pull-up resistors for input signals. =====
 +If connector J1 is used for inputs like GCA93 and GCA94, it is better to use pull-resistors.\\
 +RP1 and RP2 are used for that.\\
 +A standard value of 10 KOhm is usually sufficient.\\
 +They are deliberately inserted in sockets, so they can be adapted in value for best performance,​ or removed when outputs are selected.\\ ​
 +For hall-sensor use, these resistor arrays should be between 470 Ohm and 1 Kohm, to guarantee a\\
 +most reliable and distorsion free functioning.\\
 +===== Schematic drawing and pcb =====
 +|  {{:​gca51_sch.pdf|The schematic drawing}} ​ |
 +|  {{:​gca:​gca51_pcb.pdf|The pcb with parts positions}} ​ | 
 +|  {{:​gca:​gca51_partslist.pdf|The bill of materials}} ​ |
 +===== Firmware =====
 +|  {{:​gca:​|The .hex for Arduino Nano}} ​ |
 +**For Window users only! (as far as I know)**.\\
 +To make it simple for programming the Nano.\\
 +The zip file above also contains a //​GCA51.hex//​ file.\\
 +Download, install and execute the program Xloader here {{:​http://​​arduino-xloader}}\\
 +Then use it to program the hex. file via USB, no Arduino program needed.\\
 +===== PCBoard and Kit =====
 +Expecting end of april 2016\\
 +===== Possible connector setup. =====
 +Two main setup options are available in this unit.\\
 +**These are all prototypes.!! Professional made pc-board are available now.**\\
 +|  SUB-D male and female for GCA LNET and  \\  1 x RJ12 for standard LocoNet ​ \\  in LTD-01 box.  |  Same without the box  |   2x RJ12 for standard LocoNet compatibility ​ \\  in LTD-01 box.  |  ​
 +|  {{:​gca:​gca51_pict03.jpg?​200}} ​ |  {{:​gca:​gca51_pict04.jpg?​200}} ​ |  {{:​gca:​gca51_pict05.jpg?​200}} ​ |
 +===== How to connect and use RC522 RFID sensor board =====
 +[[RC522-sensor-board.en|Click here for the RC522 page]]
 +{{ :​gca:​rc522_with_pss254-8w_connector.gif?​150}}
gca51-en.txt ยท Last modified: 2018/11/12 08:56 (external edit)