Yongnuo YN600II firmware v1.40

V1.40 2022/4/7

1. Improved stability.

V1.39 2021/1/16

1. Improve the TTL compatibility of the R5 camera.

V1.38 2019-012-16

1. Improve EOS-R camera TTL exposure.

V1.37 2019-07-23

1. Improve EOS R camera compatibility.

V1.36 2018-12-17

1. Repair abnormal display of slave indicator
2. Improving compatibility between the flash and EOS-M6

V1.35 2018-11-8

1. Add the focal length adjustment function of​ slave unit
2. Improve the wireless flash system

V1.32 2018-05-31

1. Repair the compatibility with 1500D/3000D camera.

V1.31 2018-03-21

1. Repair the compatibility with canon 430EX-RT III flash.

V1.29 2017-11-13 1｡｢Fix the TTL exception problem when the power switch is in "LOCK" state.

V1.28 2017-10-31

1. Enhance stability of flash wireless radio.
2. Repair modeling flash problem in wireless slave mode.
3. Improve overheating protection test.
4. Improve recycle time.

V1.27 2017-09-22

1. Add "external power source charge only" function(C.Fn 12).
2. Fixed hibernation problem.
3. Other improvement.

V1.26 2017-8-30

1. Repair: It causes the crash when you restore the flash custom settings.

V1.25 2017-8-19 1.improve the stability of TTL mode. 2.other improvement.

V1.23 2017-07-31 1.improve the compatibility of EOS-M6. 2.added wireless single contact trigger function(Legacy Trigger) .

V1.22 2017-07-21 1.repaire overheating protection easily problem in multi mode.

V1.21 2017-07-11 1.improve the compatibility of TTL mode. 2.repair incorrect grouping problem in multi flashing of Sc mode. 3.other improvement.

V1.20 2017-06-15

1. Enhance the stability of the radio.
2. Improve compatibility with 5D Mark IV.
3. Repair exposure voice prompt.

V1.19 2017-06-06

1. Fix the slave unit charging status prompt error problem.
2. Other improvent.

V1.18 2017-05-10

1. Improve the over-exposure problem when using wireless radio slave ETTL​ mode with 80D camera.
2. Fix the flash brightness problem when using wireless master MULTI mode.

V1.17 2017-04-17 Optimize the wireless flash system.

V1.16 2017-04-08

1. Improve the compatibility with 5D MARK IV.
2. Correct the over-expose problem when using wireless radio master ETTL mode on 5D MARK IV.
3. Other improvement

V1.13 2017-02-28 Repair: When the speedlite is set at radio Gr mode, the function button [ON/OFF] cannot operation problem.

V1.12 2016-12-24 Optimize the firmware upgrade. Optimize the screen display.