# Modbus Adressing **URL:** \ **Category:** Ignition\ **Tags:** ignition79\ **Created:** [July 24, 2020, 1:45pm UTC](https://forum.inductiveautomation.com/t/modbus-adressing/37049 "2020-07-24T13:45:33Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Oleh](https://avatars.discourse-cdn.com/v4/letter/o/b4bc9f/32.png) [@Oleh](https://forum.inductiveautomation.com/u/Oleh)\ **Post date:** [July 24, 2020, 1:45pm UTC](https://forum.inductiveautomation.com/t/modbus-adressing/37049/1 "2020-07-24T13:45:33Z")
Please help with modbus adressing. How to read registers from a modbus card? ![Modbus](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/0/709cfd4db1ca5e2aeb2f184eee5c74db8a78be6e.png) ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [July 24, 2020, 3:46pm UTC](https://forum.inductiveautomation.com/t/modbus-adressing/37049/2 "2020-07-24T15:46:57Z")
Modbus function code 3 is ‘read holding registers’ - so the first block of addresses should be HR160 (`0x00A0` in hex is 160 in decimal) and HR859 (`0x35B`). The telecontrol command will be a coil (function code 5) so most likely either: C12289 (`0x3001`) or C3001. [https://docs.inductiveautomation.com/display/DOC80/Modbus+Addressing](https://docs.inductiveautomation.com/display/DOC80/Modbus+Addressing) If you can’t find those particular addresses, try toggling the ‘One/Zero Based Addressing’ setting in the device’s configuration. If you get the holding registers connected and can’t write to them, try disabling ‘Allow Write Multiple Registers Request’ in the settings - function code 6 is specifically to write a single register, so the device may not support the (much more efficient) ‘Write Multiple Registers’ request.