Yealink SIP-T54S Administrator's Manual page 175

The following table lists the associated and latest firmware name for each IP phone model (X is
replaced by the actual firmware version).
IP Phone Model
SIP-T54S/T52S
(T5S firmware unified)
SIP-
T48S/T46S/T42S/T41S
(T4S firmware unified)
SIP-T48G
SIP-T46G
SIP-T42G
SIP-T41P
SIP-T40P
SIP-T40G
SIP-T29G
SIP-T27P
SIP-T27G
SIP-T23P/G
SIP-T21(P) E2
SIP-T19(P) E2
CP860
CP920
You can download the latest firmware online:
Note
http://support.yealink.com/documentFront/forwardToDocumentFrontDisplayPage.
Do not unplug the network and power cables when the IP phone is upgrading firmware.
Upgrading Firmware from the Provisioning Server
IP phones support using FTP, TFTP, HTTP and HTTPS protocols to download configuration files
and firmware from the provisioning server, and then upgrade firmware automatically.
IP phones can download firmware stored on the provisioning server in one of two ways:
Check for configuration files and then download firmware during startup.

Automatically check for configuration files and then download firmware at a fixed interval

or specific time.
Associated
Firmware Name Example
Firmware Name
70.x.x.x.rom
66.x.x.x.rom
35.x.x.x.rom
28.x.x.x.rom
29.x.x.x.rom
36.x.x.x.rom
54.x.x.x.rom
76.x.x.x.rom
46.x.x.x.rom
45.x.x.x.rom
69.x.x.x.rom
44.x.x.x.rom
52.x.x.x.rom
53.x.x.x.rom
37.x.x.x.rom
78.x.x.x.rom
Configuring Basic Features
70.81.0.10.rom
66.81.0.40.rom
35.81.0.40.rom
28.81.0.40.rom
29.81.0.40.rom
36.81.0.40.rom
54.81.0.40.rom
76.81.0.40.rom
46.81.0.40.rom
45.81.0.40.rom
69.81.0.40.rom
44.81.0.40.rom
52.81.0.40.rom
53.81.0.40.rom
37.81.0.10.rom
78.81.0.10.rom
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