Search results

Exception 3 is Illegal Data Value. The value you're writing is outside of the allowable range for that register. According to your documentation, register 502 has a range from 0 - 99. Try reading address 501 first, you will likely see [0, 39] for the values returned. Then if you write [0, 41]...

I've never used QuickHMI, but it would seem to make sense that if you want to access Holding Register 9, then you would reference it as hr9, not hr8 (unless QuickHMI uses 0-based addressing instead of 1-based). More importantly, though, Modbus registers are 16-bit integers, so you should be...

What is the heating device you're trying to control? Do you have any Modbus documentation for it that you can share? It's possible this could be due to an "off-by-one" issue with the register address you're trying to access, especially since it's a 32-bit register that you're trying to access...

ICC is happy to help you with your configuration, and can even provide you a sample configuration for your application to help get you started. If you would like to take advantage of this complementary service, please submit a support ticket at https://www.iccdesigns.com/hesk/ For purchasing...

If you only have 2 Modbus RTU networks, then 2 ETH-1000 gateways would be lower cost and less complicated to install and configure than 2 Mirius gateways and an ETH-1000 (RTU to TCP gateway). Therefore, I recommend using 2 ETH-1000 gateways for your application.

Unfortunately, I'm not familiar with those Schneider products. Perhaps someone more familiar with Schneider can help you on the specifics. But in general, yes you would need to have your Modbus Master send multiple Modbus frames targetting different registers in order to read more data.

The Modbus protocol is not limited to 128 registers (words). I think you may be confusing the limitation of the number of registers that fit in a single Modbus packet. A Modbus packet is limited to 256 bytes in total. Therefore, the number of registers (words) that fit in a read registers...

Thank you for the update. I'm glad to hear you got it working accessing 32-bit registers instead of the 64-bit double registers.

To test the radio connection and communication, you could connect both radios to your laptop (using a USB to RS-232 adapter for each radio) and use Modbus software such as ModScan and ModSim (https://www.win-tech.com/), as both of these have hardware handshaking settings. I recommend that you...

I was able to Google a manual for the pDDL900 here: http://www.isnmp.com/download/pddl900/pDDL900_manual.pdf However, I could not find any information or manual for a Safecore gas detector, other than that it may be part of this Radius BZ1 Area Monitor...

Unfortunately I don't have much experience working with radios, but I can provide some general comments on Modbus RTU and the settings you've shown in your attachment that may help. Modbus RTU uses a minimum of 3.5 character times to delimit each packet. Therefore, your "Character Timeout"...

Based on the values your program is outputting for STEP2 - STTEP4, the temp_int64 variable is only 32 bits (instead of 64). You need to use "long long temp_int64;" for the temp_int64 declaration instead of "long temp_int64;". Additionally, the Arduino's Serial.print function may not support...

Three main problems. 1. You absolutely need to use 74 instead of 75 for the address. The reason you're not getting a response is because you haven't recalculated your CRC when you changed 75 to 74. The entire packet should be this: {0x01, 0x03, 0x00, 0x74, 0x00, 0x04, 0x04, 0x13} Please...

You're not copying the correct data bytes from the received packet. You need to change these lines: reg_data[0] = (((unsigned short)byteSend[0]) << 8) | ((unsigned short)byteSend[1]); reg_data[1] = (((unsigned short)byteSend[2]) << 8) | ((unsigned short)byteSend[3]); reg_data[2] = (((unsigned...

There is one additional thing to watch out for, since you are reading the packet manually, byte-by-byte and not using a Modbus library. Each 16-bit Modbus register uses big-endian byte ordering, i.e. high byte then low byte, as per the Modbus specification. But the ordering of the 16-bit...

I'm sorry, I'm not very familiar with the Arduino's libraries, but a Google search turns up this as the first result: https://arduino.stackexchange.com/questions/10088/what-is-the-difference-between-serial-write-and-serial-print-and-when-are-they According to that link, you need to use...

If the Modbus library you're using on your Arduino uses 0-based addressing (which is how the address is encoded into the Modbus packet itself), make sure to start at register 116 instead of 117 so that you see the same hex value in your Arduino as ModScan showed. You don't need to understand...

OK, so register 117 is encoded as a double data type and when you select the double data format in ModScan, you see the correct value. It seems that you got it working correctly. Now, this is different than your original post, so what changed? Your original post had a hex value of...

You can find request and response examples right in the Modbus spec here: https://modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf Take a look at section 6.3 for the 03 (0x03) Read Holding Registers example. Of course, with Modbus ASCII, all packets will start with the colon ':'...

I understand that this is the sensor's raw Modbus response, but you don't state what registers you're reading to receive that data. Like I said before, I think you may need to add 1 to your register address (i.e. if you were using 109, you need to use 110 instead) and reverse the ordering of the...