How to keep the IO port in BlueNRG-1 sleep mode

kingk

How to keep the IO port in BlueNRG-1 sleep mode [Copy link]

 

I am testing the sleep mode function of BLUENRG-1. I read the official documentation and found that in sleep mode, except for a few IO ports with internal IO9, IO0, and IO11, the other IO ports are in high impedance state. This leads to a question, how to maintain the status of the IO ports. It is fine in CPU_HALT mode, but not in deep sleep mode. One of the tested IO ports lights up, Bluetooth broadcasts for 1 second, and then enters the deep sleep mode loop, showing the following situation

1) It goes off, on, off, on. When it's on, it's just a little bit of light.

2) If a device is connected to Bluetooth and enters the connection state, the originally controlled LED light will flash at a fast frequency, but basically remain on. However, the brightness is obviously dimmer than before entering the Bluetooth cycle.

If I want to keep control of an IO port and use deep sleep, what should I do?

I thought of adding latches, but this adds circuitry and I don't think it should be necessary.

kingk

nmg has a FAQ post

https://en.eeworld.com/bbs/thread-1101045-1-1.html

But it is for bluenrg-2. I currently have bluenrg-1 modules, so I want to ask if I can only use bluenrg-2 to solve the IO port retention problem in the future.

@nmg

littleshrimp

From the existing information, BlueNRG-1 does not have the power-off IO retention function

What if the LED remains off when the BlueNRG-1 is powered off, and the BlueNRG-1 keeps the CPU running when it is powered on?

LEDs consume more power when they are on. When it comes to low power consumption, they should not be on for too long. If this is done, it is equivalent to adding the power consumption of BlueNRG-1 when the LED is on. By properly controlling the LED lighting time, the impact on the overall power consumption should not be too great.

lucienkuang

Hello

When BlueNRG-1 is in sleep mode, all IO ports cannot remain in the target state and can only be in the default state (see the official datasheet for details).

3.12.2.2 GPIO characteristics

If I want to keep control of an IO port and use deep sleep, what should I do?

I'm sorry to tell you that for this problem, you can only replace the chip, such as BlueNRG-2 (there are three GPIOs that can be maintained during sleep), BlueNRG-LP (next generation chip, coming soon, so stay tuned)

lucienkuang

The main purpose of the OP is to optimize power consumption. If this is the purpose, BlueNRG-1 can also be optimized. For example, if the OP wants the LED light to be on for one second, every second, then CPU_HALT can be used in the second of on-time, and SLEEPMODE_WAKETIMER can be used in the second of sleep.

If the LED is on and off for one second each, the current of the LED itself is in the milliampere level. In this way, the average current will be 1.9mA/2 = 0.95mA higher than the maintained current.

The power consumption is about 7uA when connected once per second. It is recommended that you consider optimizing the proportion of lights on from the wake-up time.

kingk

lucienkuang posted on 2020-3-24 14:52 Hello BlueNRG-1 When in sleep mode, all IO ports cannot remain in the target state and can only be...

I have learned about the LP chip from the agent and hope to launch it as soon as possible. I have a need for long range. I don't want to use networking because it is a bit troublesome and it will increase the workload and I am not very familiar with it.

lucienkuang

kingk posted on 2020-3-25 18:29 I have learned about the LP chip from the agent and hope to launch it as soon as possible. There is a demand for long range. I don't want to network it, it's a bit troublesome...

If you have a specific project, you can try to apply for related boards and design materials. It is expected that new products can be mass-produced before the design and development of your project is completed. There are already related development boards.