Command Reference

Index

1. About
2. Core AT Commands
3. AT& extended commands
4. AT+ commands
5. AT$ configuration variables
6. ATS registers

About

This contains a full list of Hayes-style AT commands compatible with the PerryZi firmware.

Core AT commands

Command	Description
AT	Attention prefix. On its own, returns OK. Prefixes all commands below.
ATA	Answer / accept a waiting incoming connection.
ATB<n>	Set the serial baud rate. A comma-separated suffix may set the line format (data/parity/stop).
ATC	Connect: bring up wifi (and/or open the pending connection).
ATD"host:port" ATDT"host:port"	Dial a remote host and enter online (stream) mode. The T in ATDT is optional, as are the quotes.
ATE<n>	Echo: E0 - off E1 - on
ATF<n>	Serial flow-control type: F0 - RTS/CTS F1 - XON/XOFF, F2 - XON/XOFF auto-off F3 - manual F4 - disabled
ATH	Hang up: close all open connections.
ATI<n>	Information: I0/I1/I5 - settings strings I2 - IP I3 - SSID I4 - firmware version I6 - MAC I7 - date/time I8 - build date I9 - network details I10 - last printer spec I11 - free heap
ATL	Re-send the last packet on a connection.
ATM	Hayes compatibility (speaker control); no operation.
ATN<n>	Create or remove a TCP listener (server) port.
ATO	Return to online (stream) mode with the current connection, or dial a phonebook entry by number.
ATP	Phonebook: list, add or remove stored dialling entries.
ATQ<n>	Quiet mode: Q1 - suppress result codes Q0 - enable result codes
ATR<n>	Line-ending mode: R0, CR, R1, CRLF, R2, LFCR, R3, or LF.
ATRD / ATRT	Display the current UTC date/time obtained via NTP from uk.pool.ntp.org in NIST time format: YY-MM-DD HH:MM:SS Implemented to maintain compatibility with ST.COM
ATS<n>? / ATS<n>=<v>	Read or write an S-register. See the ATS registers table below.
ATT	Transmit a data packet to the current connection (optional CRC).
ATV<n>	Result-code style: V0 - numeric V1 - verbose
ATW	WiFi: scan/list access points, or connect with: ATW"SSID,PASSWORD"
ATX<n>	Result-code set: X0 - short X1 - long/extended
ATY	Hayes compatibility; no operation.
ATZ	Reset the modem and reload the last saved configuration.

AT& extended commands

Command	Description
AT&D<c>	Append a character to the delimiter set.
AT&F	Factory reset. To also reformat the SPIFFS filesystem: AT&F86
AT&G	Fetch/stream a web URL to the terminal.
AT&K<n>	Flow-control shortcut: 0/1/2 - off 3/6 - RTS/CTS 4/5 - XON/XOFF.
AT&L	Reload configuration from flash.
AT&M<c>	Append a character to the "mask-out" set (bytes stripped from the stream).
AT&N<n> / AT&N<n>=<v>	Read or force a GPIO pin.
AT&O<n>	Start logging if no argument is provided. Debug log control: &O0 - dump log &O86/&O87 - delete &O88 - log and echo to UART
AT&S<n>=<value>	Set a string setting: S40 - mDNS hostname S41 - terminal type S42 - busy message
AT&T	Show the current time. Configure the timezone: AT&T<args>
AT&W	Save the current configuration to flash.
AT&Y...	Define the escape/state-machine sequence.

AT+ commands

Command	Description
AT+CONFIG	Enter the interactive configuration menu.
AT+IRC	Enter IRC chat mode.
AT+PING"host"	Ping a host to test connectivity/DNS.
AT+PPP	Enter PPP networking mode.
AT+PRINT<mode>:<host>:<port>/<path>	Print to a CUPS/IPP printer. Mode is Ascii, or Raw.
AT+SLIP	Enter SLIP networking mode.

AT$ configuration variables

Command	Description
AT$MDNS=<value>	Set the mDNS hostname.
AT$PASS=<value>	Set the wifi password.
AT$SB=<value>	Set the serial baud rate.
AT$SSID=<value>	Set the wifi SSID.

ATS registers

Read a register with ATS<n>? and set one with ATS<n>=<v>.

Register	Meaning	Values
S0	Auto-answer: number of rings before answering an incoming connection (0 disables auto-answer).	0 to 255
S2	Escape character used in the +++ escape sequence.	0 to 255
S3	Carriage-return character code.	0 to 127
S4	Line-feed character code.	0 to 127
S5	Backspace character code.	0 to 32
S40	Streaming packet size, in bytes.	≥ 1
S41	Auto-stream mode; enter stream mode automatically on answer/connect:	0 - off >0 - on
S42	CRC-8 value used by the transmit command (ATT).	0 to 255
S43	Temporary baud rate applied to the next dialled connection.	baud rate ≤0 - clear
S44	Inter-character serial output delay, in milliseconds.	≥ 0
S45	Binary translation type for streaming.	0 to (BTYPE_INVALID−1)
S46	DCD line polarity mode.	0 - normal 1 - inverted 2 - always active 3 - always inactive
S47	GPIO pin assigned to DCD (output).	supported pin 0 to MAX_PIN_NO
S48	CTS line polarity mode.	0 - normal 1 - inverted 2 - always active 3 always inactive
S49	GPIO pin assigned to CTS (input).	supported pin 0 to MAX_PIN_NO
S50	RTS line polarity mode.	0 - normal 1 - inverted 2 - always active 3 - always inactive
S51	GPIO pin assigned to RTS (output).	supported pin 0 to MAX_PIN_NO
S52	RI (ring indicator) line polarity mode.	0 - normal 1 - inverted 2 - always active 3 - always inactive
S53	GPIO pin assigned to RI (output).	supported pin 0 to MAX_PIN_NO
S54	DTR line polarity mode.	0 - normal 1 - inverted 2 - always active 3 - always inactive
S55	GPIO pin assigned to DTR (input).	supported pin 0 to MAX_PIN_NO
S56	DSR line polarity mode.	0 - normal 1 - inverted 2 - always active 3 - always inactive
S57	GPIO pin assigned to DSR (output).	supported pin 0 to MAX_PIN_NO
S60	Preserve TCP listeners across resets (persisted to flash).	0 - off non-0 - on
S61	Printer job completion timeout, in seconds.	> 0
S62	Telnet protocol handling on connections.	0 - off >0 - on
S63	Hang-up trigger type.	0 - none 1- PPP-hard 2 - DTR 3 - PDP
S64	Discard incoming NUL bytes.	0 - off >0 - on