# Address configuration for s7 1200 as OPC device **URL:** \ **Category:** Ignition\ **Created:** [September 28, 2024, 10:17pm UTC](https://forum.inductiveautomation.com/t/address-configuration-for-s7-1200-as-opc-device/96583 "2024-09-28T22:17:09Z")\ **Posts on this page:** 1\ **Showing post:** 24
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [October 1, 2024, 2:20pm UTC](https://forum.inductiveautomation.com/t/address-configuration-for-s7-1200-as-opc-device/96583/24 "2024-10-01T14:20:39Z")
> [@gary\_truell](#): > > correct syntax for controlling a bit Based on your earlier error report, the Modbus implementation in Siemens doesn't support the necessary "Masked Write" function code to change bits in holding registers, and doesn't support the coil function codes. So, no can do with Modbus. It should be possible with the native driver using boolean tag syntax as Kevin suggested in [comment #17 above](https://forum.inductiveautomation.com/t/address-configuration-for-s7-1200-as-opc-device/96583/17), as long as you satisfy all of the preconditions for the native driver's use with S7 1200/1500 devices: > **[Siemens | Ignition User Manual](https://www.docs.inductiveautomation.com/docs/8.1/ignition-modules/opc-ua/opc-ua-drivers/siemens#considerations-for-1200-and-1500-devices)** > > The Siemens drivers in Ignition support basic connections to S7 devices. Ignition connects to these PLCs via TCP/IP using the S7 protocol. Similar to Modbus and some Allen Bradley connections, the Siemens S7 devices do not support tag browsing. You... (An S7+ driver is coming in Ignition v8.3, which should simplify this considerably.) --- _[View the full topic](https://forum.inductiveautomation.com/t/address-configuration-for-s7-1200-as-opc-device/96583)._