EOE-W55RP20 SNMP Module AT Command Guide

Firmware 1.2.0 · 61 commands

AT commands are exchanged on uart1 (GP4 TX / GP5 RX). The factory default is 115200 8N1, no flow control.

The console log goes out separately on uart0, so it never mixes into the AT port.

For installation and connecting an SNMP manager, see the SNMP Setup Guide.

Chapter	Contents
Chapter 1	Syntax and rules
Chapter 2	Command list
Chapter 3	Device control
Chapter 4	Network
Chapter 5	SNMP agent and product identity
Chapter 6	SNMPv3 users and communities
Chapter 7	Objects and OID mapping
Chapter 8	Notifications (Trap · Inform)
Chapter 9	TCP · UDP socket channels
Chapter 10	Web management
Chapter 11	Firmware update (OTA)
Chapter 12	URCs (unsolicited messages)
Chapter 13	Error codes
Chapter 14	Alphabetical index

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1. Syntax and rules

1.1 Forms

AT                       check the module answers
AT+NAME=<value>          set
AT+NAME?                 query
AT+NAME                  execute (action without arguments)
AT+NAME=?                test (not executed)

Each command supports different forms. They are listed in the table in Chapter 2 Command list.

1.2 Rules

Item	Value
Case	Command names and keywords are case-insensitive
Strings	Enclose in double quotes. A comma inside quotes is not a separator
Numbers	Decimal and 0x hexadecimal are both accepted. Leading zeros are ignored (0161 = 161)
Line ending	CR, LF and CRLF are all accepted. Responses always end with CRLF
Line length	256 bytes maximum. Longer lines are not executed: ERROR:BUFFER_TOO_LONG
Arguments	12 maximum

• More arguments than required are refused. AT+IP="1.2.3.4",5 returns ERROR:INVALID_PARAMETER and the address is not changed.
• A query must end at ?. AT+OBJVAL?900 and AT+VERSION?x return ERROR:INVALID_PARAMETER. No query takes arguments.
• To skip an argument in the middle, keep its comma: AT+USMADD="mon",NOAUTHNOPRIV,,,,,MONITOR
• Out-of-range values and negative numbers are refused as they are, never adjusted. A port number is 1 … 65535 in every command; outside that the result is ERROR:VALUE_OUT_OF_RANGE.
• AT+NAME=? is the test form. The command is not executed; the answer is OK if it has a set form and ERROR:INVALID_COMMAND if it does not.

1.3 Responses

Every command ends with a single OK on success or ERROR:<code> on failure (Chapter 13). Queries and some set commands send one or more +NAME:... lines before that.

AT+SNMPPORT?
+SNMPPORT:161
OK

1.4 When settings take effect

Set commands change memory only. Storing to flash and actually applying the settings is done by AT+SAVE.

AT+NETMODE=STATIC
AT+IP="192.168.0.100"
AT+MASK="255.255.255.0"
AT+GW="192.168.0.1"
AT+SAVE

Commands that act immediately, without AT+SAVE:

Command	Why
AT+OBJVAL · AT+SETACK	Values, not settings
AT+SOCK*	Channels are not stored
AT+TRAPSEND · AT+INFORMSEND	Send actions
AT+OTAFWUP	Receive action
AT+OIDMAPRELOAD · AT+OIDMAPCLEAR	Change the mapping directly
AT+FACTORY · AT+REBOOT · AT+OTAREBOOT	Reboot immediately

AT+OBJADD and AT+OBJDEL change the object table immediately, but without AT+SAVE the change is gone at the next boot.

1.5 Binary mode

AT+SOCKSEND and AT+SOCKSENDTO declare a length first, then accept exactly that many bytes of raw data after the > prompt.

AT+SOCKSEND=0,5
> HELLO
+SOCKSEND:0,5
OK

• In binary mode CR, LF, NUL and even the letters AT are all data.
• No line break follows the > prompt. In the bytes the module sends, the result arrives on the same line as the prompt, as in > +SOCKSEND:0,5. A host that reads line by line should recognise the prompt as the two bytes > , not as a line, and strip a leading > from the result line.
• Send all the declared bytes within 10 seconds of the prompt. After 10 seconds the command ends with ERROR:PAYLOAD_TIMEOUT, even if bytes are still arriving.
• End command lines with CRLF. An LF right after a CR is taken as the end of the line and dropped, so a host that ends lines with CR alone loses the first byte of a payload that starts with LF (0x0A).
• On a port configured for 7 bits or XONXOFF, the transfer is refused before it starts (ERROR:NOT_SUPPORTED).

1.6 Limits

All lengths are in bytes. Non-ASCII characters take more than one byte in UTF-8 (a Korean character, for example, takes 3).

Item	Limit	If exceeded
AT line	256	BUFFER_TOO_LONG
Arguments	12	INVALID_PARAMETER
Socket send	1460	BUFFER_TOO_LONG
Object name	19	INVALID_PARAMETER
Object string value	63	INVALID_PARAMETER
String value of a PERSISTENT object	44	BUFFER_TOO_LONG
Object OID	16 arcs, 20 bytes encoded	OID_TOO_LONG
SNMPv3 user name	32	INVALID_PARAMETER
Authentication · privacy password	63	INVALID_PARAMETER
Community name	32	INVALID_PARAMETER
Web account	23	INVALID_PARAMETER
Web password	63 (minimum 8)	INVALID_PARAMETER
Socket host name	63	INVALID_PARAMETER

Item	Count
Objects	1024 (of which 128 can be strings)
SNMPv3 users	4
Communities	4
Notification receivers	4
Socket channels	4

The string value limit depends on the path: 63 bytes over AT, 64 bytes over an SNMP SET, and 44 bytes for a PERSISTENT object (AT+OBJVAL).

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2. Command list

Column	Meaning
Set	Supports the AT+NAME=<value> form
Query	Supports the AT+NAME? form
Exec	Supports the AT+NAME form
Save	● means AT+SAVE is required. — means the command stores by itself

2.1 Device control (Chapter 3)

Command	Set	Query	Exec	Save	Function
AT			●		Check the module answers
AT+SAVE			●	—	Store settings to flash and apply
AT+REBOOT			●	—	Close connections and reboot
AT+FACTORY	●			—	Factory reset
AT+VERSION		●			Firmware, model, serial, product ID
AT+DIAG		●			Statistics and diagnostics
AT+UART	●	●		●	AT port settings

2.2 Network (Chapter 4)

Command	Set	Query	Exec	Save	Function
AT+NETMODE	●	●		●	DHCP / STATIC
AT+IP	●	●		●	IP address
AT+MASK	●	●		●	Subnet mask
AT+GW	●	●		●	Gateway
AT+DNS	●	●		●	DNS server

2.3 SNMP agent (Chapter 5)

Command	Set	Query	Exec	Save	Function
AT+SNMP	●	●		●	Agent on/off
AT+SNMPPORT	●	●		●	Listening port (default 161)
AT+SNMPVER	●	●		●	SNMP versions answered (default 3)
AT+ENGINEID		●			Engine ID (read-only)
AT+ENGINEBOOT		●			Engine boot count
AT+SYSOBJID	●	●		●	sysObjectID
AT+SYSDESCR	●	●		●	sysDescr (description)
AT+SYSNAME	●	●		●	sysName (host name)
AT+SYSCONTACT	●	●		●	sysContact (contact)
AT+SYSLOCATION	●	●		●	sysLocation (location)
AT+PRODUCTID	●	●		●	Product ID override
AT+PRODUCTARC	●	●		●	Product arc for automatic OID placement

2.4 Users and communities (Chapter 6)

Command	Set	Query	Exec	Save	Function
AT+USMADD	●			●	Add or change an SNMPv3 user (up to 4)
AT+USMDEL	●			●	Delete a user
AT+USMUSER		●			List users
AT+COMMADD	●			●	Add or change a community (up to 4)
AT+COMMDEL	●			●	Delete a community
AT+COMM		●			List communities

2.5 Objects (Chapter 7)

Command	Set	Query	Exec	Save	Function
AT+OBJADD	●			●※	Define an object
AT+OBJATTR	●	●		●※	Object attributes (set mode, range, unit, description, default)
AT+OBJDEL	●			●※	Delete an object
AT+OBJVAL	●	●			Write and read values
AT+OBJ		●			Query object definitions
AT+SETACK	●				Answer a confirmed SET
AT+OIDMAP		●			Mapping status
AT+OIDMAPRELOAD			●		Re-apply the stored CSV
AT+OIDMAPCLEAR	●				Clear the user mapping

※ The object table changes immediately, but without AT+SAVE it is gone at the next boot.

2.6 Notifications (Chapter 8)

Command	Set	Query	Exec	Save	Function
AT+TARGETADD	●			●	Register a receiver (up to 4)
AT+TARGETDEL	●			●	Delete a receiver
AT+TARGET		●			List receivers
AT+TARGETKEY	●			●	Register a receiver's localized keys
AT+TRAPSEND	●				Send a Trap
AT+INFORMSEND	●				Send an Inform

2.7 Sockets (Chapter 9)

Command	Set	Query	Exec	Save	Function
AT+SOCKAVAIL		●			Channels available to open
AT+SOCKSTATUS		●			Channel status list
AT+SOCKOPEN	●				Open a channel
AT+SOCKCLOSE	●				Close a channel
AT+SOCKSEND	●				Send (binary mode)
AT+SOCKSENDTO	●				UDP send to a given destination
AT+SOCKPEER	●				Default UDP peer
AT+SOCKOPT	●	●			Socket options

2.8 Web (Chapter 10)

Command	Set	Query	Exec	Save	Function
AT+WEB	●	●		●	Web interface on/off
AT+WEBUSER	●	●		●	Login account
AT+WEBPASS	●			●	Set password (no query)
AT+WEBTIMEOUT	●	●		●	Session timeout

2.9 Firmware update (Chapter 11)

Command	Set	Query	Exec	Save	Function
AT+OTAFWUP	●				Send firmware over UART
AT+OTASTATUS		●			Progress status
AT+OTACANCEL			●		Cancel an update
AT+OTAREBOOT			●		Reboot into the staged image

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3. Device control

AT (check the module answers)

AT
OK

AT+SAVE (store and apply)

AT+SAVE
OK

Stores the settings to flash and applies them (1.4).

• Object definitions created with AT+OBJADD are stored at the same time.
• Network, SNMP and web settings are re-applied only if they actually changed.
• If the network settings change, all open sockets are closed.

AT+REBOOT (reboot)

AT+REBOOT

After sending the response, closes the socket channels and the network services in turn and reboots. Peers receive a normal connection close, so no dead connection is left on their side.

AT+FACTORY (factory reset)

AT+FACTORY="CONFIRM"
+FACTORY:COMPLETE

Erases the settings, stored object values and the stored OID CSV, then reboots.

Erased	Kept
Network, SNMP and web settings, AT port settings	MAC address
SNMPv3 users, communities	Serial number
Object definitions and values, OID mapping	Model name, product ID

• "CONFIRM" must match exactly, including case.
• If an OTA image is staged, the command is refused with ERROR:OTA_PENDING.
• The web interface and the FAC_RSTn pin (held for 5 seconds) also reset the device.
• After the reset the AT port returns to 115200, 8, NONE, NONE.

AT+VERSION? (version and identity)

AT+VERSION?
+VERSION:"1.2.0","EOE-ioNIC_SNMP","EOE-ioNIC_SNMP-0008DC360034",0x454F4501

Firmware version · model · serial · product ID currently in effect.

AT+DIAG? (statistics and diagnostics)

AT+DIAG?
+DIAG:SOCKETS,<open>,<free>,<open failures>,<accept failures>,<exhaustion>
+DIAG:SNMP,<get>,<getnext>,<getbulk>,<set>,<access denied>
+DIAG:USM,<unknown user>,<wrong digest>,<decrypt error>,<outside time window>
+DIAG:PORT,<speed>,<bits>,<parity>,<flow control>,<DTR|NODTR>,<READY|HELD>
+DIAG:RXDROP,<dropped bytes>,<FIFO overrun 0|1>
+DIAG:STORAGE,<content>,<state>
+DIAG:ATTX,<queued items>,<queued bytes>,<dropped items>
+DIAG:WATCHDOG,<enabled>,<timeout ms>
+DIAG:CHIP,<OK|UNRESPONSIVE>,<checks>,<recoveries>

Value	If non-zero
RXDROP	The module missed incoming bytes. Enable flow control or lower the speed
ATTX dropped items	The transmit queue was full and URCs or data were dropped
CHIP recoveries	The Ethernet chip has been recovered at least once
USM wrong digest	Password or algorithm does not match the manager

• PORT shows what this port is actually running at now. A difference from the stored value is reported by PENDING in AT+UART?.
• If the last two PORT fields are NODTR,HELD, the host has lowered DTR and transmission is held.

AT+UART (AT port settings)

AT+UART=<speed>,<data bits>,<parity>,<flow control>
AT+UART?     → +UART:115200,8,NONE,NONE,ACTIVE

Argument	Values
Speed	9600 19200 38400 57600 115200 230400 460800 921600
Data bits	7 · 8
Parity	NONE · ODD · EVEN
Flow control	NONE · RTSCTS · DTRDSR · XONXOFF

• All four arguments are required. Stop bits are always 1 and cannot be set.
• Parity and flow control are given by name. Unknown names are refused.

When it takes effect

AT+UART=230400,8,NONE,RTSCTS
OK
AT+SAVE
OK                          ← still 115200
AT+REBOOT                   ← applied here

Last field of AT+UART?	Meaning
ACTIVE	The stored values match the current port settings
PENDING	Stored but not yet applied. A reboot is required

Flow control

Value	Method	Direction
NONE	None (factory default)	—
RTSCTS	Hardware. GP6 (module CTS) / GP7 (module RTS)	Both
DTRDSR	Watches DTR on GP8	Module transmit only
XONXOFF	In-band 0x11 / 0x13	Both

7 bits strips the top bit of every byte, and XONXOFF interprets 0x11 and 0x13 inside a payload as flow-control signals. Both change the data without reporting an error, so with these settings AT+SOCKSEND and AT+OTAFWUP are blocked entirely.

AT+UART=115200,7,EVEN,RTSCTS
+UART:BINARYOFF,7BIT
OK

Commands and responses are ASCII, so they still work at 7 bits. Only binary transfers are blocked.

A wrong setting is hard to undo. If the module comes up with new settings the host cannot match, the AT port cannot be used to recover. What remains is the web interface (Chapter 10) and the FAC_RSTn pin.

• A speed not in the list returns ERROR:VALUE_OUT_OF_RANGE; an unknown name returns ERROR:INVALID_PARAMETER.
• AT+FACTORY also returns these settings to their defaults.

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4. Network

AT+NETMODE (address assignment)

AT+NETMODE=DHCP
AT+NETMODE=STATIC
AT+NETMODE?          → +NETMODE:DHCP

AT+IP · AT+MASK · AT+GW · AT+DNS (address settings)

AT+IP="192.168.0.100"
AT+MASK="255.255.255.0"
AT+GW="192.168.0.1"
AT+DNS="8.8.8.8"
AT+SAVE

AT+IP?               → +IP:"192.168.0.100"

The factory default is STATIC 192.168.11.2 / 255.255.255.0 with gateway 192.168.11.1.

• Set changes the value to be stored; query reads the value the module is using now. Under DHCP the two normally differ, because the leased address is not written to the settings.
• AT+DNS? is the exception: it reports the DNS address the firmware is using.
• If AT+SAVE actually changes the network settings, all open sockets are closed. Closed channels are not reopened automatically.

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5. SNMP agent and product identity

AT+SNMP (agent on/off)

AT+SNMP=1
AT+SNMP=0
AT+SNMP?             → +SNMP:1

AT+SNMPPORT (listening port)

AT+SNMPPORT=161      1 … 65535
AT+SNMPPORT?         → +SNMPPORT:161

The query reports the stored value. Until AT+SAVE, it can differ from the port that is actually open.

AT+SNMPVER (SNMP versions answered)

AT+SNMPVER=3         v3 only (factory default)
AT+SNMPVER=2,3       v2c and v3
AT+SNMPVER=1,2,3     all three
AT+SNMPVER?          → +SNMPVER:2,3

This is a list, not a single value. Setting only v2c turns v3 off, which also cuts the SNMPv3 access used to configure the device.

• Requests in a version not in the list get no response; only an internal counter is incremented. That counter can be read over SNMP at 1.3.6.1.2.1.11.3.0 (snmpInBadVersions).
• Listing the same version twice is refused (1,1 · 3,3).
• An empty list returns ERROR:INVALID_PARAMETER. To stop the agent, use AT+SNMP=0.
• Registering a community has no effect unless its version is enabled here.

Differences under v1

v2c · v3	v1
Counter64 value	GET returns noSuchName. GETNEXT skips the object
noSuchObject · noSuchInstance · endOfMibView	noSuchName
A SET with a bad value (wrongType, wrongValue, wrongLength, ...)	badValue
A target that cannot be written (notWritable, noCreation, noAccess)	noSuchName
Anything else, such as commitFailed	genErr
GETBULK	Does not exist. A v1 message containing it gets no response

As a result, walking the same objects with SNMPv1 returns fewer entries, one fewer for each Counter64 object.

AT+ENGINEID? (engine ID)

AT+ENGINEID?         → +ENGINEID:"8000CECE030008DC123456"

(Enterprise number | 0x80000000) in 4 bytes + format byte 0x03 + 6-byte MAC. Read-only; it changes if the MAC changes.

SNMPv3 keys are derived together with this value, so if the engine ID changes, every registered user key becomes invalid.

AT+ENGINEBOOT? (engine boot count)

AT+ENGINEBOOT?       → +ENGINEBOOT:37

A monotonically increasing value used for the SNMPv3 time window.

AT+SYSOBJID (sysObjectID)

AT+SYSOBJID="1.3.6.1.4.1.12345.1.1"
AT+SYSOBJID=""                          revert to default
AT+SYSOBJID?         → +SYSOBJID:"1.3.6.1.4.1.52942",DEFAULT
                     → +SYSOBJID:"1.3.6.1.4.1.12345.1.1",CONFIGURED

This value tells the manager which company's product the device is. The module is a component, so set it to the enterprise OID of the end-product manufacturer. If it is not set, the module answers with its own manufacturer's number.

• At least 2 arcs are required.
• This value alone is not subject to the product enterprise subtree check.
• It is read-only over SNMP.

AT+SYSDESCR · AT+SYSNAME · AT+SYSCONTACT · AT+SYSLOCATION (description, name, contact, location)

AT+SYSDESCR="Acme UPS-3000 controller"  up to 63 characters
AT+SYSNAME="ups-lab-03"                  up to 31 characters
AT+SYSCONTACT="ops@example.com"           up to 63 characters
AT+SYSLOCATION="Seoul HQ, B2, rack 4"     up to 63 characters
AT+SYSCONTACT=""                          clear
AT+SYSDESCR=""                            back to the module's own text
AT+SYSDESCR?         → +SYSDESCR:"Acme UPS-3000 controller",CONFIGURED
AT+SYSNAME?          → +SYSNAME:"ups-lab-03"
AT+SYSCONTACT?       → +SYSCONTACT:"ops@example.com"
AT+SYSLOCATION?      → +SYSLOCATION:"Seoul HQ, B2, rack 4"
AT+SAVE

The description (sysDescr), name (sysName), contact (sysContact) and location (sysLocation) an SNMP manager shows in its device list. Set them so that each installed device can be told apart.

• While sysDescr is not set (or after ""), the module answers its own text, EOE-ioNIC_SNMP SNMPv3 module, firmware <version>. DEFAULT or CONFIGURED in the query result says which. With sysDescr set, check the firmware version with AT+VERSION?.

• AT+SYSNAME is the same value as Hostname on the web interface's Network tab. Changing it does not drop network connections.

• Only printable ASCII (letters, digits, space and symbols) is allowed, and " is not. Non-ASCII text is ERROR:INVALID_PARAMETER; a value that is too long is ERROR:BUFFER_TOO_LONG. A comma inside the quotes is part of the value.

• Takes effect at once; send AT+SAVE to keep it across a reboot.

• sysDescr, sysContact and sysLocation can also be set on the web interface's Identity tab.

• Read-only over SNMP.

AT+PRODUCTID (product ID override)

AT+PRODUCTID=0x00010002    set override
AT+PRODUCTID=0             clear override
AT+PRODUCTID?
  +PRODUCTID:0x00010002,OVERRIDE
  +PRODUCTID:FACTORY,0x454F4501      ← only while overridden

The product ID is used to refuse OTA packages meant for other products. An override disables that check, so every place the value is shown also indicates whether it is overridden.

Marker	Meaning
FACTORY	Value from the factory record
OVERRIDE	Value set by this command
PLACEHOLDER	Value never assigned

0 clears the override; it is not a value.

AT+PRODUCTARC (product arc for automatic OID placement)

AT+PRODUCTARC=7      → new objects at <enterprise>.7.<id>.0
AT+PRODUCTARC=0      → new objects at <enterprise>.<id>.0
AT+PRODUCTARC?       → +PRODUCTARC:7,SET  /  +PRODUCTARC:0,NONE

Where objects are placed when AT+OBJADD omits the OID. It applies only to objects created from now on; existing objects do not move.

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6. SNMPv3 users and communities

Up to 4 SNMPv3 users and up to 4 v1/v2c communities. The two tables are separate: deleting from one does not free a slot in the other.

AT+USMADD (add or change an SNMPv3 user)

AT+USMADD="<name>",<level>[,<auth>,"<auth-pw>"[,<priv>,"<priv-pw>"]][,<role>]

Argument	Values
level	NOAUTHNOPRIV · AUTHNOPRIV · AUTHPRIV
auth	SHA256 · SHA1 (= SHA)
priv	AES128 (= AES)
role	ADMINISTRATOR · OPERATOR · MONITOR · NOTIFICATION (default OPERATOR)

AT+USMADD="admin",AUTHPRIV,SHA256,"auth-password",AES128,"priv-password"
AT+USMADD="mon",NOAUTHNOPRIV,,,,,MONITOR
AT+SAVE

role	Access
ADMINISTRATOR	Read and write all objects
OPERATOR	Read and write regular objects
MONITOR	Read only
NOTIFICATION	For receiving Traps / Informs

• role is always the 7th position. Keep the commas even for a level that needs no keys.
• MD5 and DES are not supported. They are refused with ERROR:NOT_SUPPORTED rather than replaced with a weaker algorithm.
• An invalid role is refused, not replaced with the default.
• The name is up to 32 bytes and each password up to 63 bytes. Longer values return ERROR:INVALID_PARAMETER.
• The same name overwrites the existing user. With no free slot, the result is ERROR:USER_LIMIT.
• Registration takes a few seconds. Wait for OK.

Passwords are not stored. They are converted at once into keys localized to the engine ID, and every plaintext copy is wiped. A lost password cannot be recovered; delete the user and create it again.

AT+USMDEL (delete a user)

AT+USMDEL="admin"
AT+SAVE

An unknown name returns ERROR:OBJECT_NOT_FOUND.

AT+USMUSER? (list users)

AT+USMUSER?
+USMUSER:"admin",AUTHPRIV,SHA256,AES128,CONFIGURED,ENABLED,Administrator

Name · level · authentication algorithm · privacy algorithm · keys configured · enabled · role.

The role is printed as Administrator · Operator · Monitor · Notification, not in the upper case used on input. Input is not case-sensitive, so the printed value can be entered again as it is. AT+COMM? does the same.

Neither passwords nor keys are returned, not even the key length.

AT+COMMADD (add or change a community)

AT+COMMADD="<name>",<role>[,<enabled>]

Argument	Values	Default
role	ADMINISTRATOR · OPERATOR · MONITOR · NOTIFICATION	None (required)
enabled	0 · 1	1

AT+SNMPVER=2,3
AT+COMMADD="ro-poll",MONITOR
AT+SAVE

• role is required and has no default. An invalid value returns ERROR:INVALID_PARAMETER.
• Access checks are the same as for USM users. A community cannot reach more than a v3 user with the same role.
• For an existing name, only the given fields change. If enabled is omitted, the existing value is kept. To disable explicitly, use AT+COMMADD="ro-poll",MONITOR,0.
• The name is up to 32 bytes.
• With no free slot, the result is ERROR:COMMUNITY_LIMIT.

AT+COMMDEL (delete a community)

AT+COMMDEL="ro-poll"
AT+SAVE

A community can be deleted even if a Trap receiver still uses it. Sending to that receiver then fails with UNKNOWN_COMMUNITY.

AT+COMM? (list communities)

AT+COMM?
+COMM:"ro-poll",Monitor,ENABLED

Name · role · enabled. Community strings are returned as they are, because SNMP already carries them in plaintext.

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7. Objects and OID mapping

Up to 1024 objects, of which up to 128 can be OctetString.

AT+OBJADD (define an object)

AT+OBJADD=<id>,"<name>",<type>,<access>[,<persistence>[,"<oid>"]]

Argument	Values
id	1 … 65535. The number the host uses to refer to this object
name	Up to 19 bytes. Longer returns ERROR:INVALID_PARAMETER
type	Integer32 Unsigned32 Gauge32 Counter32 Counter64 TimeTicks OctetString IpAddress
access	RO · RW
persistence	VOLATILE (default) · PERSISTENT
oid	Placed automatically if omitted. Up to 16 arcs and 20 encoded bytes

AT+OBJADD=1,"temperature",Integer32,RO,VOLATILE
AT+OBJADD=3,"relay1",Integer32,RW,PERSISTENT
AT+OBJADD=9,"custom",Gauge32,RO,VOLATILE,"1.3.6.1.4.1.52942.9.0"
AT+SAVE

• If the OID is omitted, the object is placed at <enterprise>[.<product arc>].<id>.0.
• An explicit OID is checked against the enterprise subtree. Outside it, the result is ERROR:OID_OUT_OF_SUBTREE.
• The value of a PERSISTENT object survives a reboot; a VOLATILE one does not.
• The mapping source changes to MANUAL_AT (AT+OIDMAP?).
• Without AT+SAVE, the definition is gone at the next boot.

**ERROR:OID_TOO_LONG is returned both for more than 16 arcs and for an OID whose BER encoding exceeds 20 B even with 16 arcs or fewer. A large number such as 52942 takes 3 B for one arc, a small one takes 1 B. 1.3.6.1.4.1.52942.a.b.c.0 is 12 B, well within the limit.

Error	Cause
DUPLICATE_ID · DUPLICATE_NAME · DUPLICATE_OID	Tells you whether the number, name or OID collided
TYPE_MISMATCH	Unknown type
INVALID_PARAMETER	Invalid access or persistence value
OBJECT_LIMIT	No free object or string slot

AT+OBJATTR (object attributes)

AT+OBJATTR=<id>,SETMODE,IMMEDIATE|CONFIRMED
AT+OBJATTR=<id>,RANGE,<min>,<max>      0,0 = no range
AT+OBJATTR=<id>,UNIT,"<unit>"           up to 7 bytes
AT+OBJATTR=<id>,DESC,"<description>"    up to 31 bytes
AT+OBJATTR=<id>,DEFAULT,<value>         integer types only, 0 = none
AT+OBJATTR?
  +OBJATTR:10,CONFIRMED,0,1,"","Relay; host must agree first",0
  +OBJATTR:2,IMMEDIATE,0,85,"degC","Board temperature",25

Adds or changes, on an object created with AT+OBJADD, the attributes a web CSV row carries. One attribute per command; the object is not deleted, so its value (PERSISTENT included) is kept.

AT+OBJADD=10,"relay",Integer32,RW,PERSISTENT
AT+OBJATTR=10,SETMODE,CONFIRMED
AT+OBJATTR=10,RANGE,0,1
AT+OBJATTR=10,DESC,"Relay; host must agree first"
AT+SAVE

Attribute	Meaning
SETMODE	With CONFIRMED, a manager's SET is not applied at once: the module asks the host with +SNMPSET:<tid>,<id>,<value>, and it is applied only when AT+SETACK approves it within 750 ms
RANGE	The value range for integer types, the length range (0 to 64) for OctetString. AT+OBJVAL and SNMP SETs outside it are refused
UNIT · DESC	Unit and description. "" clears them
DEFAULT	The starting value when the object is created or the device boots. The current value is not changed. A PERSISTENT object's stored value takes precedence

• A range that the current value falls outside is refused. Change the value first, then narrow the range.
• IpAddress and Counter64 take no range; OctetString and IpAddress take no default.
• The mapping source becomes MANUAL_AT. Without AT+SAVE the change is gone at the next boot. The attributes also appear in the web CSV export.

Error	Cause
OBJECT_NOT_FOUND	No object with that id
VALUE_OUT_OF_RANGE	A range or default does not fit the type, or the current value or the default is outside the range
TYPE_MISMATCH	That attribute cannot be given to this type
BUFFER_TOO_LONG	The unit or description is too long
INVALID_PARAMETER	Wrong attribute name or value format, or min is greater than max

AT+OBJDEL (delete an object)

AT+OBJDEL=1
AT+SAVE

AT+OBJVAL (write and read values)

AT+OBJVAL=1,253
AT+OBJVAL=5,"Busan-Lab-B"
AT+OBJVAL=7,"192.168.0.9"

AT+OBJVAL?
+OBJVAL:1,"temperature",1.3.6.1.4.1.52942.1.0,253

• No AT+SAVE needed. The value takes effect immediately.
• The value is interpreted according to the type. Counter64 accepts the full 64 bits.
• An out-of-range value returns ERROR:VALUE_OUT_OF_RANGE.
• String values are up to 63 bytes; longer returns ERROR:INVALID_PARAMETER. The same object accepts up to 64 bytes through an SNMP SET.
• Strings in a PERSISTENT object are limited to 44 bytes, because a longer value does not fit the storage record. Longer values are refused with ERROR:BUFFER_TOO_LONG and the value is left unchanged.
• The query returns the whole list. AT+OBJVAL?<id> is not supported.
• Object definitions are not touched, so the mapping source does not change.

AT+OBJ? (query object definitions)

AT+OBJ?
+OBJ:1,"temperature",1.3.6.1.4.1.52942.1.0,Integer32,RW,PERSISTENT,IMMEDIATE,"C"

id · name · OID · type · access · persistence · SET mode · unit.

Field	Values
Access	RO · RW
Persistence	PERSISTENT · VOLATILE
SET mode	IMMEDIATE · CONFIRMED (set only through CSV)

AT+OBJVAL? answers with values; this command answers with definitions.

AT+SETACK (answer a confirmed SET)

+SNMPSET:27,3,1          ← confirmation request from the module (request no., object no., value)
AT+SETACK=27,OK          → approve
AT+SETACK=27,FAIL        → reject

• Answer within 750 ms. If the deadline passes, the manager receives an error and a late answer returns ERROR:HOST_TIMEOUT.
• Anything other than OK is treated as a rejection, but the answer must be 7 bytes or shorter. A longer one such as ERROR:BUSY is itself refused with ERROR:INVALID_PARAMETER, and the SET fails after the 750 ms deadline. Send FAIL to reject.

AT+OIDMAP? (mapping status)

AT+OIDMAP?
+OIDMAP:CSV_IMPORT,64,3,32768,0xA1B2C3D4,ACTIVE

Source · object count · CSV schema version · original size · original CRC32 · active state.

Source	Meaning
DEFAULT	No user mapping
MANUAL_AT	Defined with AT commands
CSV_IMPORT	Imported from a CSV via the web interface
CSV_IMPORT_MODIFIED	Imported from a CSV, then changed with AT

The original CSV content is not returned over AT.

AT+OIDMAPRELOAD · AT+OIDMAPCLEAR

AT+OIDMAPRELOAD              re-parse and apply the stored CSV
AT+OIDMAPCLEAR="CONFIRM"     clear the user mapping

• With no stored CSV the result is ERROR:CSV_NOT_AVAILABLE; with a corrupt one, ERROR:INVALID_CSV. A CSV with a header line and no object rows is also INVALID_CSV. To empty the mapping, use AT+OIDMAPCLEAR="CONFIRM".
• CSV upload is available only through the web interface.

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8. Notifications (Trap · Inform)

Up to 4 receivers, index 0 … 3.

	Trap	Inform
Acknowledgement	Not checked	Waits for a response
On failure	Ends as is	Retried, then ERROR:NOTIFY_NO_RESPONSE

AT+TARGETADD (register a receiver)

AT+TARGETADD=<idx>,"<ip>",<port>,"<user>",<level>
              [,<type>[,<retry>[,<timeout>[,<version>[,"<community>"]]]]]

Argument	Values	Default
type	TRAP · INFORM	TRAP
retry	0 … 255	3
timeout	1 … 65535 (ms)	1000
version	V1 · V2C · V3	V3
community	Required for v1/v2c, not allowed for v3	—

AT+TARGETADD=1,"192.168.0.20",162,"trapuser",AUTHPRIV
AT+TARGETADD=2,"192.168.0.21",162,"informuser",AUTHNOPRIV,INFORM,5,2000
AT+TARGETADD=3,"192.168.0.22",162,"",,TRAP,3,1000,V2C,"ro-poll"
AT+SAVE

• v1/v2c receivers have no user and no security level. Leave those two positions empty.
• Out-of-range retry or timeout values are refused, not clamped.
• Registering again at the same index erases the receiver keys stored there.
• Whether the community exists is checked when sending, not when registering.
• The user name and the community name are each up to 32 bytes.
• INFORM for a V1 receiver returns ERROR:NOT_SUPPORTED. SNMPv1 has no Inform at all, and a Trap is not sent in its place.

AT+TARGETDEL · AT+TARGET?

AT+TARGETDEL=1

AT+TARGET?
+TARGET:1,"192.168.0.20",162,"trapuser",TRAP,KEYED,AUTHPRIV,3,1000,V3,""
+TARGET:3,"192.168.0.22",162,"",TRAP,NOKEY,NOAUTHNOPRIV,3,1000,V2C,"ro-poll"

Index · address · port · user · type · keys registered · security level · retry · timeout · version · community. The keys themselves are not returned.

AT+TARGETKEY (register a receiver's localized keys)

AT+TARGETKEY=<idx>,"<engine-id-hex>","<auth-key-hex>"[,"<priv-key-hex>"]
AT+TARGETKEY=1,"","",""        clear

Needed only for authenticated v3 Informs. Keys localized to the receiver's engine ID are required, and since this device does not hold passwords, the keys are computed outside and entered here (inform_keys.md).

• Sending an authenticated Inform without keys returns ERROR:ACCESS_DENIED.
• Not needed for Traps or v2c Informs.

AT+TRAPSEND · AT+INFORMSEND

AT+TRAPSEND=<trap-id>[,<object-id>]
AT+INFORMSEND=<trap-id>[,<object-id>]

AT+TRAPSEND=1001,2
AT+INFORMSEND=1001,2

Sent to every registered receiver. The command decides whether it is a Trap or an Inform; the type stored for a receiver changes only through the 6th argument of AT+TARGETADD.

Error	Cause
NOTIFY_NO_RESPONSE	The Inform got no response through all retries
UNKNOWN_COMMUNITY	The receiver's community is missing or disabled
UNKNOWN_USER	The USM user a v3 receiver names does not exist
ACCESS_DENIED	Authenticated Inform without keys

A v2c Inform response is accepted only if the request-id, the community and the source address all match.

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9. TCP · UDP socket channels

Logical channels 0 … 3, with a maximum payload of 1460 bytes per send. The channel number is the host's own number and has nothing to do with the socket numbers inside the Ethernet chip.

AT+SOCKAVAIL? · AT+SOCKSTATUS?

AT+SOCKAVAIL?
+SOCKAVAIL:2

AT+SOCKSTATUS?
+SOCKSTATUS:0,TCP_CLIENT,ESTABLISHED,"192.168.0.20",5000,40001
+SOCKSTATUS:1,TCP_SERVER,LISTENING,"0.0.0.0",0,5001
+SOCKSTATUS:2,UDP,OPEN,"0.0.0.0",0,6000

States: CLOSED OPENING LISTENING CONNECTING ESTABLISHED CLOSING OPEN ERROR.

A UDP channel is OPEN, not ESTABLISHED. It sends and receives normally in that state.

AT+SOCKOPEN (open a channel)

AT+SOCKOPEN=0,TCP_CLIENT,"192.168.0.20",5000
AT+SOCKOPEN=0,TCP_CLIENT,"server.example.com",5000
AT+SOCKOPEN=0,TCP_CLIENT,"192.168.0.20",5000,40001    with local port
AT+SOCKOPEN=1,TCP_SERVER,5001
AT+SOCKOPEN=2,UDP,6000

• With no free resources the result is ERROR:NO_SOCKET. Existing channels are never closed to make room.
• Every connection failure returns ERROR:CONNECT_FAILED; the reason comes in the +SOCKERROR line sent just before it.
• Ports are 1 … 65535. The local port may be omitted.
• A TCP server accepts one client per channel.
• The host name is up to 63 bytes.

AT+SOCKCLOSE · AT+SOCKPEER

AT+SOCKCLOSE=0
AT+SOCKPEER=2,"192.168.0.30",7000      default UDP peer

AT+SOCKSEND · AT+SOCKSENDTO

AT+SOCKSEND=<ch>,<len>
AT+SOCKSENDTO=<ch>,"<host>",<port>,<len>

AT+SOCKSEND=0,5
> HELLO
+SOCKSEND:0,5
OK

For the binary mode rules, see 1.5.

• The second number in the response is the number of bytes actually sent. It can be smaller than requested.
• A len of 0 returns INVALID_PARAMETER; over 1460 returns BUFFER_TOO_LONG.
• On a channel that cannot send, ERROR:NOT_CONNECTED is returned before the prompt.
• AT+SOCKSENDTO works on a UDP channel only, and the port (1 … 65535) and address (not 0.0.0.0) are also checked before the prompt.
• Received data arrives as +SOCKRX · +SOCKRXFROM URCs (Chapter 12).

AT+SOCKOPT (socket options)

AT+SOCKOPT=<ch>,<option>,<value>
AT+SOCKOPT?

Option	Applies to	Value
KEEPALIVE	TCP	0 / 1
KEEPIDLE	TCP	seconds, 0 … 65535 (outside: VALUE_OUT_OF_RANGE)
NODELAY	TCP	0 / 1
BROADCAST	UDP	0 / 1

A TCP option on a UDP channel, or the reverse, returns ERROR:NOT_SUPPORTED.

---

10. Web management

The web interface is disabled by default, and it can be turned on only over AT. Its address is http://<IP>:50003/ (the port cannot be changed).

From the factory there is no web password, so no one can log in. Set one with AT+WEBPASS before turning the web on. The account name defaults to admin.

AT+WEB · AT+WEBUSER · AT+WEBPASS · AT+WEBTIMEOUT

AT+WEB=1                 enable the web interface
AT+WEB=0                 disable
AT+WEB=1,600             enable + session timeout of 600 s (1 … 65535)
AT+WEB?                  → +WEB:1,600,SET

AT+WEBUSER="admin"
AT+WEBUSER?              → +WEBUSER:"admin"

AT+WEBPASS="new-password"   8 … 63 bytes
AT+WEBTIMEOUT=600        1 … 65535 s
AT+WEBTIMEOUT?           → +WEBTIMEOUT:600
AT+SAVE

Third field of AT+WEB?:

Value	Meaning
MUSTCHANGE	No password yet. Nobody can log in until one is set with AT+WEBPASS
SET	A password is set

• There is no AT+WEBPASS?. The password is stored only in a form that cannot be reversed, so there is nothing to answer with.
• The account is up to 23 bytes and the password up to 63 bytes.
• One connection is served at a time. When requests come back to back, the later connection can be refused for a moment, so a script should retry once.

---

11. Firmware update (OTA)

There are two ways: upload through the web interface, or AT+OTAFWUP. Neither installs immediately. The received image is verified, stored in a staging area and installed at the next boot. If the transfer fails or is interrupted, the running firmware stays in place.

AT+OTAFWUP (send firmware over UART)

AT+OTAFWUP=<seconds>     idle timeout, 1 … 600

Sequence

AT+OTAFWUP=30
+OTAFWUP:READY                 ← staging area ready. Send the whole file now
<the entire .fwpkg file>
+OTAFWUP:IMAGE,1.2.0,218980    ← header accepted. Version and image size
+OTAFWUP:DONE,218980,1.2.0
OK

• There is no step at which to pause. After +OTAFWUP:READY, send the whole file in one go.
• +OTAFWUP:IMAGE is a progress notice, not a prompt.
• Wait for READY. Right after the command the module erases the staging area for about 0.5 s, during which reception stops and anything sent is lost.
• No progress is reported during the transfer. Check how much arrived with AT+OTASTATUS?.

Tera Term

1. Type AT+OTAFWUP=30
2. Wait for +OTAFWUP:READY (about 0.5 s)
3. File → Send file → tick Binary → select the .fwpkg
4. Check for +OTAFWUP:DONE and OK, then AT+OTAREBOOT

Flow control is not required. At the factory default (115200 8N1, no flow control) a package of about 214,000 bytes goes through in 19 seconds without loss. When raising the speed, RTSCTS is recommended.

When it looks stuck

+OTAFWUP:IMAGE,1.2.0,218980
(...no response...)

The module is waiting for the rest of the package. In this state every byte you type goes in as firmware data and restarts the idle timer from zero.

**Take your hands off and wait <seconds>; the module returns to command mode on its own.

+OTAFWUP:ERROR,TIMEOUT,183253,218980,OVERRUN
ERROR:PAYLOAD_TIMEOUT

This means only 183,253 of 215,164 bytes arrived.

Marker	Meaning	Action
OVERRUN present	The host sent everything but the module did not receive it all	Enable flow control or lower the speed
OVERRUN absent	The host stopped partway	Check the file and the transfer tool

Refusals and failures

+OTAFWUP:ERROR,PRODUCT,0xFFFF0001,0x454F4501
ERROR:INVALID_IMAGE

The first value is the package's product ID, the second the module's. The module value is the fourth field of AT+VERSION?.

URC	Response	Meaning
+OTAFWUP:ERROR,MAGIC	INVALID_IMAGE	Not a firmware package
+OTAFWUP:ERROR,HEADERCRC	INVALID_IMAGE	The header is corrupt
+OTAFWUP:ERROR,PRODUCT,<package>,<module>	INVALID_IMAGE	Built for another product. A trailing ,OVERRIDDEN means the module value is an override
+OTAFWUP:ERROR,HWREV,<min>,<max>,<module>	INVALID_IMAGE	Hardware revision out of range
+OTAFWUP:ERROR,SIZE	INVALID_IMAGE	Image size out of range
+OTAFWUP:ERROR,HEADER	INVALID_IMAGE	A header value does not match this device
+OTAFWUP:ERROR,UNSUPPORTED	INVALID_IMAGE	Header version or required bootloader version is too high
+OTAFWUP:ERROR,IMAGECRC	INVALID_IMAGE	Content check failed. Detected after everything is received
+OTAFWUP:ERROR,NOTAPP	INVALID_IMAGE	The package is intact but is not firmware the module can start. Detected after everything is received
+OTAFWUP:ERROR,BUSY	STORAGE_BUSY	Storage is in use by something else
+OTAFWUP:ERROR,STORAGE	STORAGE_FAILURE	Flash write failed
+OTAFWUP:ERROR,TIMEOUT,<received>,<total>	PAYLOAD_TIMEOUT	The host stopped partway
+OTAFWUP:ERROR,TIMEOUT,<received>,<total>,OVERRUN	PAYLOAD_TIMEOUT	The module missed some bytes
+OTAFWUP:ERROR,PORT,"<reason>"	NOT_SUPPORTED	The port cannot carry 8 bits

• However it ends, the port returns to AT command mode.
• After a refusal, leftover bytes may be read as command lines and a few ERROR:INVALID_COMMAND lines may follow. One empty line (CR) clears them.
• The staging area is erased before the header is checked. Even for a refused file, whatever was there before has already been erased.

Port requirements

The transfer does not start at 7 bits or with XONXOFF. Change to 8 bits with NONE, RTSCTS or DTRDSR using AT+UART and try again.

DTRDSR can be used. However, if the host keeps DTR low, +OTAFWUP:READY does not appear and the module waits. The idle timeout counts reception, so it does not end this wait. Raising DTR lets the transfer continue.

AT+OTASTATUS? (progress status)

AT+OTASTATUS?
+OTASTATUS:DOWNLOADING,131072,262144,50

State · bytes received · total size · progress (%). States: IDLE HEADER ERASING DOWNLOADING VERIFYING READY FAILED.

AT+OTACANCEL · AT+OTAREBOOT

AT+OTACANCEL         cancel the update in progress
AT+OTAREBOOT         reboot into the staged image

• With nothing staged, both return ERROR:OTA_NOT_STAGED.
• AT+OTACANCEL also works after the transfer has finished and the state is READY.
• AT+OTAREBOOT closes connections in the same order as AT+REBOOT.
• An image uploaded through the web interface is installed by a reboot the module makes by itself 5 seconds later. An AT+OTACANCEL in that time discards the image and the reboot does not happen.

---

12. URCs (unsolicited messages)

These arrive at any time without a request from the host. They share the transmit path with command responses, so they can appear before or after an OK.

URC	Category	Meaning
+READY:"1.2.0"	Device	Boot complete. Bytes sent on the AT port before this line are discarded
+LINK:UP / +LINK:DOWN	Network	Ethernet link changed
+IPCHANGED:"<ip>","<mask>","<gw>"	Network	Addresses applied again (see below)
+SNMPSET:<obj>,<value>	Object	An immediate SET was applied
+SNMPSET:<tid>,<obj>,<value>	Object	Confirmed SET. Answer with AT+SETACK
+NOTIFYFAIL:<idx>,<reason>	Notification	A notification could not be sent
+SOCKCONNECTED:<ch>,"<ip>",<port>	Socket	TCP client connected
+SOCKACCEPTED:<ch>,"<ip>",<port>	Socket	TCP server accepted a client
+SOCKRX:<ch>,<len>	Socket	Data received. Raw bytes follow
+SOCKRXFROM:<ch>,"<ip>",<port>,<len>	Socket	UDP data received. Raw bytes follow
+SOCKDISCONNECTED:<ch>,<reason>	Socket	Channel closed
+SOCKERROR:<ch>,<reason>	Socket	Socket error
+FACTORY:COMPLETE	Device	Factory reset complete

URC	Reason values
+SOCKDISCONNECTED	REMOTE_CLOSE ERROR NETWORK_RECONFIGURED ADDRESS_CHANGED MODULE_RESET
+SOCKERROR	CONNECTION_TIMEOUT CONNECTION_RESET CONNECTION_REFUSED CONNECTION_ABORTED CONNECTION_CLOSED INVALID_DESCRIPTOR UNREACHABLE NO_RESOURCE UNKNOWN
+NOTIFYFAIL	NO_RESPONSE NO_KEYS UNKNOWN_USER UNKNOWN_COMMUNITY AGENT_DOWN FAILED

UNKNOWN_USER means a v3 receiver names a USM user that does not exist (AT+USMUSER?); UNKNOWN_COMMUNITY means a v1/v2c receiver names a community that is missing or disabled (AT+COMM?). They are fixed in different places.

When the Ethernet cable is pulled. +LINK:DOWN is sent, but open socket channels are not closed. When the cable is plugged back in, a TCP connection simply carries on. If data sent while the cable was out is not acknowledged within the retransmission limit, that channel ends with +SOCKERROR.

A 0x00 after a reset. When the module resets, one 0x00 byte can arrive in front of the first line after the reset. That line is +READY with DHCP and +IPCHANGED with a static address. Depending on the host UART it shows as a framing error or a break. The module's TX pin (GP4) goes low for a moment during the reset. Look for URCs within the line rather than comparing from its first byte, and ignore a 0x00 in front of it. An external pull-up on GP4 (for example 10 kΩ) is recommended in the hardware design.

+IPCHANGED is sent every time the module applies its addresses, and the three values are the IP address, subnet mask and gateway now in use.

• At boot. Before +READY with a static address; with DHCP, once the address is obtained (after +READY)
• After an address setting is changed and AT+SAVE is sent. Nothing is sent if nothing changed
• When DHCP gives a new address. A renewal with the same address sends nothing

Applying the addresses again closes every open socket channel (+SOCKDISCONNECTED comes first). An SNMP manager has to use the new address as well.

A channel that is already closed does not get a second notification.

---

13. Error codes

ERROR:<code>

Code	Meaning
INVALID_COMMAND	Unknown command, does not start with AT, or that form is not supported
INVALID_PARAMETER	Argument format, count or range is wrong
BUFFER_TOO_LONG	A line over 256 B, a payload over 1460 B, or a value too long to store
OBJECT_NOT_FOUND	No such object, user, receiver or request number
TYPE_MISMATCH	Unknown object type
ACCESS_DENIED	Refused for security (e.g. an authenticated Inform sent without keys)
VALUE_OUT_OF_RANGE	The value is outside the range of its type
HOST_TIMEOUT	The confirmed SET deadline (750 ms) passed
NO_SOCKET	Not enough socket resources
INVALID_CHANNEL	Channel number outside 0 … 3
ALREADY_OPEN	The channel is already open
NOT_CONNECTED	The channel is not in a state that can send
CONNECT_FAILED	The connection failed (reason in +SOCKERROR)
PAYLOAD_TIMEOUT	The binary payload did not arrive in full within 10 seconds
SOCKET_OVERFLOW	The receive queue overflowed
STORAGE_BUSY	Storage is in use by another operation
OTA_PENDING	Refused because firmware is waiting to be installed
OTA_NOT_STAGED	No firmware is waiting to be installed
INVALID_CSV	The CSV could not be parsed
INVALID_IMAGE	The firmware package failed verification (reason in +OTAFWUP:ERROR)
MAPPING_TOO_LARGE	The mapping exceeds capacity
CSV_NOT_AVAILABLE	No CSV is stored
STORAGE_FAILURE	Could not write to flash
USER_LIMIT	No free SNMPv3 user slot (4 users)
COMMUNITY_LIMIT	No free community slot (4). Separate from the user table
UNKNOWN_COMMUNITY	The receiver's community is missing or disabled
UNKNOWN_USER	The USM user a v3 receiver names does not exist
NOTIFY_NO_RESPONSE	The Inform got no response through all retries
OID_OUT_OF_SUBTREE	The OID is outside the product enterprise range
OID_TOO_LONG	The OID is too long: more than 16 arcs, or more than 20 bytes encoded
DUPLICATE_ID · DUPLICATE_NAME · DUPLICATE_OID	That number, name or OID is already in use
OBJECT_LIMIT	No free object or string slot
NOT_SUPPORTED	Unsupported algorithm or option
INTERNAL	Internal error

---

14. Alphabetical index

Command	Ch.	Command	Ch.
AT	3	AT+SNMP	5
AT+COMM	6	AT+SNMPPORT	5
AT+COMMADD	6	AT+SNMPVER	5
AT+COMMDEL	6	AT+SOCKAVAIL	9
AT+DIAG	3	AT+SOCKCLOSE	9
AT+DNS	4	AT+SOCKOPEN	9
AT+ENGINEBOOT	5	AT+SOCKOPT	9
AT+ENGINEID	5	AT+SOCKPEER	9
AT+FACTORY	3	AT+SOCKSEND	9
AT+GW	4	AT+SOCKSENDTO	9
AT+INFORMSEND	8	AT+SOCKSTATUS	9
AT+IP	4	AT+SYSCONTACT	5
AT+MASK	4	AT+SYSDESCR	5
AT+NETMODE	4	AT+SYSLOCATION	5
AT+OBJ	7	AT+SYSNAME	5
AT+OBJADD	7	AT+SYSOBJID	5
AT+OBJATTR	7	AT+TARGET	8
AT+OBJDEL	7	AT+TARGETADD	8
AT+OBJVAL	7	AT+TARGETDEL	8
AT+OIDMAP	7	AT+TARGETKEY	8
AT+OIDMAPCLEAR	7	AT+TRAPSEND	8
AT+OIDMAPRELOAD	7	AT+UART	3
AT+OTACANCEL	11	AT+USMADD	6
AT+OTAFWUP	11	AT+USMDEL	6
AT+OTAREBOOT	11	AT+USMUSER	6
AT+OTASTATUS	11	AT+VERSION	3
AT+PRODUCTARC	5	AT+WEB	10
AT+PRODUCTID	5	AT+WEBPASS	10
AT+REBOOT	3	AT+WEBTIMEOUT	10
AT+SAVE	3	AT+WEBUSER	10
AT+SETACK	7