--- title: "Norvi Arita. Controller on ATmega2560" url: "https://maker.wiznet.io/mayuri/resellers/norvi-arita-controller-on-atmega2560/" markdown_url: "https://maker.wiznet.io/mayuri/resellers/norvi-arita-controller-on-atmega2560/md" type: "VAR: Value-Added Reseller Products" author: "smart_alex" author_url: "https://habr.com/ru/company/timeweb/blog/711948/" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "smart_alex" original_url: "https://habr.com/ru/company/timeweb/blog/711948/" published: "2023-02-06" language: "en" hardware: ["WIZnet W5500"] likes: 3 views: 251 comments: 1 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # Norvi Arita. Controller on ATmega2560 > Today we review the long-awaited NORVI Arita controller on the ATmega2560. It is long-awaited because most manufacturers Original author: smart_alex (source: https://habr.com/ru/company/timeweb/blog/711948/) ## Components - **WIZnet W5500** x 1 ([docs](https://docs.wiznet.io/Product/Chip/Ethernet/W5500)) WIZnet parts: W5500 ([Datasheet](https://docs.wiznet.io/Product/Chip/Ethernet/W5500/datasheet?utm_source=maker&utm_medium=project&utm_campaign=w5500), [product hub](https://maker.wiznet.io/products/w5500/)) ## Article [*![](https://habrastorage.org/r/w1560/webt/zd/ck/ir/zdckiraclgh7vopoha8u6waapdc.jpeg)*](https://habr.com/ru/post/711948/) Today we review the long-awaited NORVI Arita controller on the ATmega2560. It is long-awaited because most manufacturers, in my opinion undeservedly, ignore the wonderful ATmega2560 microcontroller, and where necessary and, most importantly, where not needed, use ESP32. ATmega2560 doesn't have Wi-Fi, but it does have "oak" 5V logic, 4 hardware Serials (on separate pins), 53/69 (!) GPIOs, 16 analog inputs, 15 PWM ports, 4KB "honest" EEPROM memory, 40 mA pin load capacity and other practically useful amenities. Against this background, the ESP32 with its ten rickety GPIOs looks like some kind of misunderstanding. In capable hands, the ATmega2560, together with the W5100/W5500 network interface and a microSD card reader (up to 32 GB), turns into a self-sufficient device with a developed (no worse than on the ESP32) web interface, huge capabilities for managing various equipment, support for complex multi-layer logic and communications with the outside world via Ethernet, LoRa, nRF24, etc., etc. There is only one problem - there is no Arduino Mega “with a human face” on the market, with rare exceptions, with one of which I I invite you to meet... ## ❯ NORVI Arita family The NORVI Arita family consists of several models (modifications), the current models are Model 5, 6, 7 and 8. This numbering indirectly indicates that there were also models 1, 2, 3, 4 and, quite possibly, models will appear 9+. *Note. **Controllers of the NORVI Arita series are also available on the STM32 core (STM32F103RBT6), but in this article we are only talking about controllers on the ATmega2560.* *![](https://habrastorage.org/r/w1560/webt/oy/gd/mg/oygdmgfp2nhhz3j-llunhpwxypy.jpeg)* The general principle of building a model range of NORVI Arita controllers is as follows: there is a certain basic model (at the moment it can be taken as Model 5), which contains 14 digital inputs, 10 relays, 2 transistor outputs and an RS485 interface (plus control buttons and indication on the front panel ). Further, in each new version, additional features are added: display, microSD card reader, W5500 Ethernet interface, etc. Moreover, some features, such as real time clock (RTC), ESP8266 Wi-Fi microcontroller, etc. are not mentioned in the documentation and on the manufacturer's website , although there is space on the controller board to install them. You can clearly see the distribution of capabilities of NORVI Arita controllers by models in the following table. Column headings for "hidden" items are greyed out. *![](https://habrastorage.org/r/w1560/webt/sr/fx/qu/srfxqutyvd6dqn5y2kw6myhqmdg.png)* Based on the information presented in the table, we can say that the most complete solution is Model 8, which contains everything you need to build a functional controller. I have at my disposal the initial Model 5 with a basic set of functions, so we will have to study some of the components and their functions “theoretically”. In the form in which the controller is available to us for research, it is a "workhorse" with 14 digital inputs, 10 relays, 2 transistor outputs and an RS485 interface, completely devoid of communication capabilities. You can use the controller "as is" to solve the corresponding tasks, or you can try to upgrade it yourself by adding an Ethernet interface or some wireless modules, such as LoRa or nRF24. Or even unsolder the missing ESP8266 module on the board, thereby adding the lost ability to work via Wi-Fi to the controller. But if you have NORVI Arita Model 8 at your disposal, then on its basis you can create very, very functional projects. By and large, there should be a Model 9, where all possible components are present and all the functionality provided by them is available for programming - this will already look like a prototype of “our dream controller”. Now let's take a closer look at the controller itself. ## ❯ Components and Features *![](https://habrastorage.org/r/w1560/webt/e2/fc/xx/e2fcxx3xnde0kv5yskbemoilbwi.jpeg)* The base model NORVI Arita Model 5 contains: - Microcontroller: ATmega2560 - 14 digital inputs (DI) - 14 input status indicators - 10 relays 220V/5A (max.) - 10 relay status indicators - 2 transistor outputs (up to 0.5A) - 2 transistor output status indicators - RS485 interface - 2 TX/RX indicators for RS485 interface activity - 4 control buttons on the front panel - Reset button - Interface for connecting additional units - Mini-USB socket for programming - 2 TX/RX USB-UART indicators - Power indicator - Supply voltage: 24 V In this configuration, first of all, there is not enough network interface on the W5500, which deprives the controller of communication capabilities and drastically limits its functionality, and a display on the front panel would not hurt - it is very convenient to display various information on it. ## ❯ Contact Location The location of contacts, control buttons and display elements of the NORVI Arita controller is shown in the illustration below. *![](https://habrastorage.org/r/w1560/webt/zv/2n/uj/zv2nuj4lrqr8odamllzdmki3qjm.png)* Here you need to make one more important remark: according to the good old tradition of NORVI controllers, in the documentation and even in the designations on the body of the product itself (!) Everything that can be confused is mixed up. You can compare the photo of the controller yourself (see above) and the actual position of the elements in the above illustration - the designations of the digital inputs IN0-IN13, PWR, RX, TX, 485 RX, 485 TX are mixed up. *Therefore, you need to connect anything to NORVI controllers with extreme caution and in no case use the official documentation and symbols on the controllers themselves - at the moment, the only reliable source of information on NORVI controllers are the articles in this series.* ## ❯ Internal arrangement *![](https://habrastorage.org/r/w1560/webt/cd/jk/4j/cdjk4jhr8lu4hflqatwc1psuwbg.jpeg)* We open the controller. Again, according to the old tradition, disassembling a NORVI controller is an activity for people with (very) straight hands, a sure eye and steely endurance, according to the principle “I will open it hard, but accurately”. The case has an almost non-separable design, which requires considerable effort to open, which can damage either the plastic of the case, or the boards and controller elements themselves. The top cover with display elements is connected to the controller using a 40-pin cable. The mini-board of indicators itself is simply glued to the top cover, and it is glued not with hot-melt adhesive, but with some kind of composition that is tightly “melted” into the plastic of the case and it is unlikely that it will be possible to disconnect the indicator board from the cover without damage. *![](https://habrastorage.org/r/w1560/webt/o7/gu/mn/o7gumnfrfhvcmeyxjnm45yxaizm.jpeg)* The transparent front panel with symbols is also removed. To the left of the indicator board is a "window" for the SSD1306 display. In my case, the display is missing and if I want to add one, I will have to cut this window into the plastic of the case. *![](https://habrastorage.org/r/w1560/webt/w6/19/nd/w619ndmsnkmjggzgphu6sjr7mfs.jpeg)* ## ❯ Circuitry The layout of the Arita family of controllers is typical for NORVI products - it is a sandwich of two boards "to death" connected by four racks of long pins. That is, it will not work to disassemble the controller (for example, for modernization) without serious surgical intervention. *![](https://habrastorage.org/r/w1560/webt/gi/l_/c7/gil_c7p8nfq8sqe5soy-3p7yza0.jpeg)* The bottom board contains contacts for connecting inputs, outputs, RS485 interface and controller power supply (24 V), elements of the power subsystem, 10 relays and other components. *![](https://habrastorage.org/r/w1560/webt/sn/ve/ep/snveepwr7djvo_hedskgflsfewi.jpeg)* The top board contains an ATmega2560 microcontroller (on the reverse side of the board), a Mini-USB connector, control buttons, a 40-pin cable connector, a configuration jumper block, and other elements. *![](https://habrastorage.org/r/w1560/webt/eh/b4/wy/ehb4wyscpieebm0h-fqzxhvp8om.jpeg)* The manufacturer does not provide a circuit diagram of the controller, so further we will have to figure it out on our own. ### Nutrition The power subsystem consists of a switching step-down voltage regulator on the LM2596S (5 V) and its piping elements. The input voltage specified by the manufacturer must be 24 V (in reality, the controller also operates from a lower voltage). *![](https://habrastorage.org/r/w1560/webt/vp/cu/tc/vpcutcwgza3obwfbyslna5n3t9a.jpeg)* View of the elements of the NORVI Arita power subsystem: the LM2596S DC-DC converter chip, inductance, filter capacitors and other elements. The normal mode is the power supply of the controller through the contacts of the pads, but it can also be partially powered from the Mini-USB connector, in this case the ATmega2560 and the indication will work and it will be possible to upload firmware to the controller. ### ATmega2560 core NORVI Arita uses the ATmega2560 microcontroller (Arduino Mega 2560) as the core, which is located on the back of the top board. Despite the fact that it has an 8-bit architecture and only 8 KB of RAM, its capabilities are more than enough for most automation tasks. *![](https://habrastorage.org/r/w1560/webt/uu/ci/av/uuciavx5f-azortypj9ch34lljw.jpeg)* The strength of this microcontroller is a large number of GPIOs (up to 69 pieces) and a huge amount of ready-made free code for it on the Internet. ### USB connection The USB-UART bridge on the NORVI Arita board is implemented using the ATmega16U2 (seen in the photo below, next to the quartz) and the controller itself is defined on the computer as "Arduino Mega 2560". There is a Mini-USB connector on the top board for connecting to a computer, programming and uploading firmware. *![](https://habrastorage.org/r/w1560/webt/vm/uh/uv/vmuhuvxx_wcckbjpscvcowf79ui.jpeg)* The photo also shows the “Reset” button, which is located on the left side of the controller case (there is a hole on the case for pressing it). ### Digital inputs NORVI Arita has 14 digital inputs connected via 4 TLP290-4 chips, each containing 4 optocouplers. *![](https://habrastorage.org/r/w1560/webt/1l/ds/nt/1ldsntqikf_ntpbqutd1kmagxzy.jpeg)* There are two options for connecting sensors to digital inputs: with a "plus" on the COM contact and with a "minus", in the terminology of the manufacturer "Sink" and "Source". ### Relay and transistor outputs NORVI Arita has 10 relay and 2 transistor outputs. The maximum current of relay outputs is 5A, transistor outputs are 500 mA. TLP290-4 chips are also used to connect them. *![](https://habrastorage.org/r/w1560/webt/db/ew/gy/dbewgyvr-orgl9pyi3uv5lnayzi.jpeg)* The relays are installed, apparently, Japanese TAKAMISAWA NY24W-K 24VDC 5A 250VAC, at least they are labeled JAPAN, which gives hope for their long and trouble-free operation (under permissible operating conditions). *![](https://habrastorage.org/r/w1560/webt/fa/es/pl/faespl8dituwxjdpeipom0mepgw.jpeg)* ### Buttons The buttons on the NORVI Arita are each connected to a separate GPIO, which is quite an acceptable luxury with so many of them in the ATmega2560 microcontroller. *![](https://habrastorage.org/r/w1560/webt/cn/ax/4p/cnax4pbiwrvbma6xe68n4pvvfwe.jpeg)* ### LED indicators NORVI Arita has a complete set of indicator LEDs. There are LEDs for inputs, outputs, controller power supply, as well as RX / TX connection to a computer and RX / TX data exchange via the RS485 interface. *![](https://habrastorage.org/r/w1560/webt/mq/eb/_p/mqeb_p09roph1rdkchkuzlq1baa.jpeg)* ### RS485 The MAX485CSA chip with the corresponding strapping elements is used as an RS485 transceiver. *![](https://habrastorage.org/r/w1560/webt/na/lp/yo/nalpyo5ifggy6zrahsuh8dheddg.jpeg)* ### 40 pin connector 40-pin connector for connecting the display board. The cable connecting both boards is made very short and it is rather problematic to connect and disconnect it. *![](https://habrastorage.org/r/w1560/webt/fz/dw/sa/fzdwsaylysopyrhvypv2ykvhrkq.jpeg)* ### Display connector The Model 5 does not have a display, but there are pads on the board for its installation, that is, if desired, the controller can be equipped with a display. True, before that, you will have to conduct a study of how Model 5 is ready for installing an SSD1306 - whether all signals are connected to the contact pads, whether it is necessary to change the jumper configuration (in the photo just above the display contacts), etc. *![](https://habrastorage.org/r/w1560/webt/4z/kt/my/4zktmyhlosikomhn4jbmigtzk2i.jpeg)* ### External connector The connector for connecting external units is placed on the right side wall of the controller. I must say that this is a rather useful addition - with the help of this connector, you can significantly expand the functionality of NORVI Arita. *![](https://habrastorage.org/r/w1560/webt/3g/1i/sj/3g1isjdmdxdlreukxc4q1qzpghk.jpeg)* True, there is one very ambiguous moment. As it turned out during the study of NORVI controllers, the pinout of the external connector does not match for different models. Up to the fact that on the same pins in some models there are GPIO pins, and in others - a supply voltage of 3.3 and 5 V. *![](https://habrastorage.org/r/w1560/webt/rj/-9/m1/rj-9m1sftgsjsborh6iujltxzd8.png)* For me, this state of affairs is completely incomprehensible, in theory, the pinout on all controllers should be the same, otherwise it is not clear how to connect additional blocks to the controllers - this way you can easily burn something. So this issue needs to be dealt with separately, at least ten times to double-check everything before connecting external units to NORVI controllers. ### Ethernet module In my case, there is no Ethernet module in the controller, but wired communication is a very important element in building automation systems, and if I upgrade NORVI Arita Model 5, then first of all I will add the W5500 module to the board (for this I will have to do one more study what and how it is connected). *![](https://habrastorage.org/r/w1560/webt/iw/dz/zs/iwdzzsa1vq9ydgehpukwaxtxhiw.jpeg)* ### Installation location of ESP8266 An additional ESP8266 microcontroller with Wi-Fi would definitely not interfere with our controller, however, despite the ready place for its installation, the presence of such an option is not even declared by the manufacturer either on the official website or in the documentation - this is again a field for our experiments and, at the same time, the opportunity to improve their skills in electronics and programming. *![](https://habrastorage.org/r/w1560/webt/lr/hy/_r/lrhy_rearefvnjcw7jq2eiybbte.jpeg)* ### Unknown module In the process of researching NORVI Arita, a place was found on the board for installing some unknown module. Neither logically nor by the location of the contact pads I was able to identify it. *![](https://habrastorage.org/r/w1560/webt/3y/sm/xt/3ysmxtvqemuon54jk4izqodjgsa.jpeg)* I don't even have any idea what it could be. Only the option with some kind of wireless module / modules comes to mind. And it would be interesting to know what should be installed there - if you have ideas - write about it in the comments. ## ❯ Pinout And finally, the pinout of the NORVI Arita controllers. Most of the GPIOs are occupied, a few free pins are most likely occupied by the Ethernet outputs of the W5500 module and the ESP8266 microcontroller, but I haven’t been able to find out for sure yet - this will become clear in the course of further research. *![](https://habrastorage.org/r/w1560/webt/ya/kl/f1/yaklf1uzi58pjn4x5_g06vnl2is.png)* Also, the location of the pins TQ.0, TQ.1 and R4 on D10, D11 and D12, which are usually used by Ethernet libraries, raises doubts - what and how it works there can only be found out in the course of practical experiments. ## ❯ Conclusion As always, there was not enough space to analyze NORVI Arita programming in one article, it will be possible to devote a separate material to this issue. It will also be possible to make a separate article on upgrading the Model 5 and turning it into a Model 8, and possibly into a Model 8+. --- Source: https://maker.wiznet.io/mayuri/resellers/norvi-arita-controller-on-atmega2560/