A Modbus TCP client for iPhone and iPad

Connect in a few taps

Enter host, port and Unit ID, or tap Find devices and pick a result. Timeout and retry count are per connection. A saved profile fills the endpoint when you tap Apply saved endpoint, so picking a profile never overwrites what you typed.

A failed connection shows the cause: timeout, refused or reset, malformed response, or a Modbus exception by name. An Illegal data address answer comes with a hint about PLC and 1-based notation.

Read all four data areas

• Coils with 01, discrete inputs with 02, holding registers with 03, input registers with 04.
• Up to 125 registers or 2000 bits per read, the protocol limit.
• Addresses in 0-based, 1-based or PLC 4xxxx notation. You can switch without disconnecting.
• Register browser shows labels, decoded and scaled values when you read through a profile.

Decode values instead of guessing

A profile stores each register's format, byte and word order, scale and unit, so 0x42F6 0xE979 reads as a temperature and not as two integers. Once it works, reuse the profile on the next site.

Monitor and chart

Add up to 16 blocks to Live monitoring and poll every 1 to 60 seconds, 2 by default. Each value gets a sparkline and a full chart. The app keeps the last 600 points or 1 hour per value while it is open, and Export CSV gives you the numbers.

Write only after you confirm

Function codes 05, 06, 15 and 16 go through Prepare write and Confirm write. The sheet lists the full target and each value. If you reconnect or change the target in between, the app cancels the write.