AT+UART_CUR should do the job but I don't think it is supported on the firmware that comes on the Espruino WiFi.
AT+UART_CUR
@dave_irvine started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
AT+UART_CUR
should do the job but I don't think it is supported on the firmware that comes on the Espruino WiFi.