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Bluno nano send string slower then use HM10.

userHead alan_0820 2016-04-11 07:41:28 6812 Views8 Replies
Hi all,

HM10 is also BLE device which use cc2540
Refer to http://fab.cba.mit.edu/classes/863.15/d ... tooth.html

I compare String transmission speed between Bluno nano's default BLE and HM10.
And find up bluno nano is much slower then HM10.


Bluno nano's BLE always sends 20bytes data, I think its root cause.
Can I change this setting? and if yes, how can I setup it?

The test use following code:

Bluno nano use default BLE
Code: Select all
void setup() {
  Serial.begin(115200);  //initial the Serial
}
 
void loop() {
    Serial.write("test");
    Serial.println();
}


Bluno with HM10
Code: Select all
#include <SoftwareSerial.h>
SoftwareSerial BT4(4, 5);

void setup() {
  Serial.begin(115200);  
  BT4.begin(115200); 
}
 
void loop() {
    BT4.write("test");
    BT4.println();
}
2019-03-02 01:33:52 Seems I'm not the only one who ran into this annoying limitation :-(

It's rather unfortunate it's not mentioned anywhere in the product specs, and that it applies even when I don't need/want the wireless programming. userHeadPic tv
2019-02-05 12:22:37 Has the firmware changed yet to allow users to send more than 20 byte packets or at least to communicate data much faster? This is also restricting my project, and if it's not fixed, I'll have to get a different Bluetooth device. userHeadPic arife1
2017-06-24 20:05:22 Excuse my ignorance but why do you use software serial to communicate? Im trying to communicate between a raspberry pi with an hm10 and a bluno nano but I can't. userHeadPic info
2016-05-18 02:24:39 Hi I asked our engineer that the speed limitation is:
  • Master ---> Slave: 2K
  • Slave ---> Master: 4K
 userHeadPic Leff
2016-05-15 21:04:21 Is the speed hard coded at 20 bytes per second? What are the limitations?
I'm experiencing extremely slow bluetooth data transmission on a project I'm working on.
It's definitely not communicating at the 115200 bps that Arduino thinks it is. It would be really nice if this limitation was published somewhere. userHeadPic salisbury.bryan
2016-04-13 02:30:25 In the future, I think it should be ok, because as I know, some people actually don't need the wireless programming feature, so the speed can be possible to be increased. userHeadPic Leff
2016-04-12 09:31:27 Unfortunately to hear this.
It's a very important mechanism used in my project, if can't speed up, then need to replace Bluno.

Will there hava a API to let user control the byte number, and speed by themselves in the fearture?
With 20 bytes per 33ms recommand / default value. userHeadPic alan_0820
2016-04-11 23:00:19 Hi Alan,

Welcome.

Sorry it can not be modified since the firmware is not open source yet. And why we made it so slow is our firmware supports wireless programming which needs reliable wireless communication. After many trails, we made it at 20bytes considering speed&stability.

I will forward your feedback to relavent person, many thanks! userHeadPic Leff
basehead
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