Is it possible to use AT commands to configure BL651?

The BL651 cannot be configured using AT commands, as the AT command set available with the BL65x modules requires loading a smartBASIC Application. Because of the limited Flash and RAM available on the BL651 it cannot support the smartBASIC firmware and therefore, the AT Interface application cannot be loaded to the module. It must be programmed using any of the developer platforms that support working with the nRF52810, such as Nordic SDK, Zephyr Project, or MyNewt, among others. All of these platforms require flashing the BLE application via the JTAG Interface, therefore it is required that you bring out the JTAG interface in order to program the BL651 module for BLE operation.