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SX1280setsleep

Hello, this is my question

My SX1280 is set

SX1280SetStandby( STDBY_RC );

SX1280SetSleep( (SleepParams_t){0x01} );

Then the microcontroller enters the stop mode. After closing all GPIO, will SX1280 stop the sleep mode?

The current phenomenon is that the shutdown of my GPIO will affect SX1280 to enter the state of sleep.

Thank you for answering my question.

Hi,
I’m guessing you’re talking about closing the GPIO of your MCU ?
I suggest you must at least leave either an internal or external pull on the CS line, to avoid a CS line glitch or state change to wake up the SX1280.
Cheers

Leaving states on CS pins doesn’t meet my low power requirements. I am looking to use GPIO to control the reset pin of 1280. Now GPIO is set to GPIO_MODE_ANALOG and the CS pin status is as follows…

I don’t get how setting CS high consumes more than setting RESET low ?

I dont see why you need to bother with RESET anyway and putting that low clears the registers and consumes a heap of current.

You can put the SX1280 to circa 1uA sleep and have it wake up registers intact. If you must clear the GPIO lines then be sure there is a pullup on CS and also make sure there are no glitches on that line.

I totally agree. I just usually reset the chip @ powercycle, but never afterwards.
CS must be kept high, as I stated earlier to avoid glitches and possibly wrongly interpreted commands (and also faulty wakeups of the SX that also drive a lot of current)

The SX128X and SX126X devices definetly need an NRESET cycle at power on, although the SX127X devices dont seem to need the same.

线路板设计的时候没有把RESET考虑进去,这是我的错误。我会改进reset引脚让它能得到有效地控制,并且CS引脚进入睡眠保持为上拉 ,很感谢你的回答,对我有很大的帮助

我很高兴帮助,玩得开心。

I would like to ask this SX1280, can the reset pin work normally without repeated pull up when it is powered on

Hello, could you tell me what the correct return instructions are? I am not sure about my return instructions 0x59 and 0x5B

I dont know what you mean by ‘return instructions’

the returned data and status codes.

0xc5 and 0xc3 ,1649576193(1)