AT Command Format

AT+<CMD>=<param1>,<param2>,...   Execute
AT+<CMD>?                        Query current state

Note

Commands that do not support execute have no = form. Use AT+<CMD>? to query their current state.

Responses:

+<CMD>:<field1>,<field2>,...
OK

ERR[:<app_err_code>]

Address bytes are always passed MSB-first without colons (e.g. C00102030405).

Parameter Types

Parameters in command format strings (fmt) use single-letter type specifiers with an optional range constraint (#~@), where # is the minimum and @ is the maximum. Omitting a bound keeps the type default.

Specifier	C type	Default range	Notes / examples
`b(#~@)`	`int8_t`	−128 to 127	`b` — any signed byte `b(-10~10)` — range −10 to 10
`B(#~@)`	`uint8_t`	0 to 255	`B` — any unsigned byte `B(1~2)` — value 1 or 2
`w(#~@)`	`int16_t`	−32768 to 32767	`w` — any signed 16-bit integer `w(-100~100)`
`W(#~@)`	`uint16_t`	0 to 65535	`W` — any unsigned 16-bit integer `W(~5)` — 0 to 5
`d(#~@)`	`int32_t`	−2147483648 to 2147483647	`d` — any signed 32-bit integer `d(-3~10)` — −3 to 10 `d(~1000)` — up to 1000
`D(#~@)`	`uint32_t`	0 to 4294967295	`D` — any unsigned 32-bit integer `D(30~)` — 30 and above
`A(#~@)`	byte array (hex)	0 to 255 bytes	`A` — any length hex string `A(6~6)` — exactly 6 bytes (e.g. BD address) `A(3~)` — at least 3 bytes `A(2~5)` — 2 to 5 bytes
`S(#~@)`	`char *` (UTF-8)	0 to 4095 bytes	`S` — any string up to 255 octets `S(3~)` — at least 3 octets `S(2~5)` — 2 to 5 octets

Note

A parameters are passed as hex-encoded strings without separators (e.g. 020106 for a 3-byte array). Each pair of hex digits is one byte. S parameters are passed as plain ASCII/UTF-8 text.