Hey people,
i have some question regarding the DA14580 Chip running in GTL Mode.
1. BLE-Firmware:
I haven´t found any bare example configuration to run in GTL mode in the SDK.
Do you know if there exists a minimal firmware with just the basic configuration to run in GTL mode?
2. our planned use-case:
Right now, our use-case includes 2 different scenarios:
1. Scenario:
The DA14580 acts in central mode.
一些在最大(6)设备连接到它并发送some information.
At some point, something (either a timer, or a remote trigger) triggers the scenario 2.
The chip should receive a reset and be reconfigured to reboot in peripheral mode.
2. Scenario:
The DA14580 now should run in peripheral mode.
As soon, as a phone connects to it, it should load all the data it has stored before onto the phone.
只要´s连接到手机,它不是possible to gather informations from the connected devices of scenario 1.
If the phone connection is lost or closed, the device should go back to scenario 1 to keep gathering informations.
Now I have a few questions:
1. Is the described mode possible?
How long would it take to completely reconfigure the device via GTL and UART from central to peripheral mode and back?
And do we need to reconnect to every device after that change?
2. Is it possible to expand the maximum of 6 users at the same time by doing kind of round-robin and always disconnect and reconnect to for example 10 devices?
Thanks a lot for your help.
Regards
Schmidt
Hi schmidt,
1) In the SDK5 in the template folder, you can use the empty_template_ext.
2) Regarding your second question some things i cannot quite understand.
The device will operate as a central and will log data from other peripherals. In some point a reset will switch the device in peripheral mode and will be connected to a phone where it will stream all the data that has been collected while operating as central to the connected phone. The question is, if you will have to connect again to the peripherals when the devices switch back in operating as central ? If that is the case then yes, the device in order to operate again as central will have to be reset and reconfigured once more, so it will have to be reconnected to all the peripherals. Regarding the second question, yes if you connect to one device (no multiple links) at a time the number of devices wont oppose limitation (kindly reminder, in peripheral mode the 580 wont be able to be connected to more than one device at a time).
Regarding the switching time, from some preliminary measurements, lets assume that the device is in central mode and not scanning, the time to issue a reset command
(GAPM_RESET_CMD) until you receive the complete event (GAPM_CMP_EVENT) from the configuration command (GAPM_SET_DEV_CONFIG_CMD) is about 45ms with no extra
command in between (the external application only sends the GAPM_RESET_CMD and GAPM_SET_DEV_CONFIG_CMD and the peripheral responds with the completetion events).
Thanks MT_dialog
Hi schimidt,
I have some additional info regarding the role switching, officially we can't guarantee anything in operating on this scheme, and regarding the switching time, allow me to make a correction regarding the time of the switching, it takes about100msNOT45ms in order to switch roles.
Thanks MT_dialog
Hi MT_dialog,
thanks a lot for your answers.
Regarding the second question:
We want to connect in Master mode to some Peripherals. The 580 can only connect to 6 devices at the same time in master mode.
Is it possible to collect data from more than 6 devices by disconnecting and reconnecting to e.g. 10 devices?
Would that be too energy- or time-consuming?
Thanks
Schmidt
Hi schmidt,
We haven't tested this kind of case, but yes i suppose that it will be power consuming, since the scanning procedure keeps the radio awake for a quite some time until you find a peripheral to connect to it, also the connection procedure is quite power consuming as well. Regarding if it will require time that depends, the connection procedure time establishment depends on quite some factors as the advertising interval of the peripheral, since it requires two advertising messages in order to be established (one adv message in order for the central to find the peripheral and issue a connection request to the stack and an additional adv message in order for the central to find the peripheral awake and issue the connection request). Also it depends on the discovery procedure, of course this happens only at the initial connection but it depends on the application you would like to implement. In general you will have to experiment with this kind of case since there are quite some factors that can enter this kind of scenario, offcourse there are also a lot of different kind of ways to overcome those problems (like using directed advertising for example - this is power consuming but it will enable you to have fast reconnections). To sum up in general connecting and reconnecting its more energy and time consuming than having 6 devices constantly connected on a central under the same circumstanses but perhpaps if you dont need to exchange data constantly but between large time intervals connecting and disconnecting might suit you, it highly depends on the application you would like to implement.
Thanks MT_dialog