Store data from ADS1293 and transfer it to Android device over BT

vix3c

Other Parts Discussed in Thread: CC2541, ADS1293, AFE4403, CC2640, CC2650

I am working on Wireless Heart Monitor with Bluetooth Low Energy, which I would like to modify it in the way that the board would record data (ECG readings) from ADS1293 chip for at least 24 hours and then transfer it over Bluetooth to the Android device (on-demand). According to CC2541 datasheet, it only comes with 8 KB RAM, which I suppose would't be enough for storing such amount of data.

I was wondering if I could replace CC2541 with one of microcontrollers which already support read/write to SD card/Flash? Which MCU should I use? Would you recommend me any better solution?

Any help would be greatly appreciated.

over 10 years ago

0 tejaChintalapati over 10 years ago

Expert 1945 points

You can interface External Flash with CC2541.

0 vix3c over 10 years ago in reply to tejaChintalapati

Intellectual 430 points

Which product specifically would you recommend?

Let me cite Brian Pisani: the ADS1293 is a 3 channel device with 24 bit data which means there is a minimum of 9 bytes per conversion. The lowest sample rate is 25 SPS so in 24 hours you would collect 24 hrs x 60 min/hr x 60 s/min x 25 samples/s = 2.16 million samples which 2.16 million samples x 9 bytes per sample puts you at nearly 20 MB.

0 DavidL over 10 years ago in reply to vix3c

TI__Mastermind 25045 points

Hi,

Not sure if you have reviewed this EVM?? It uses an afe4403 instead of the AD1293, but you might find it useful.

www.ti.com/.../afe4403-hrevm

Best regards,

David

0 vix3c over 10 years ago in reply to DavidL

Intellectual 430 points

No, I haven't seen it yet, but it certainly looks relevant to my interests, thanks! Would it be possible to get datasheet/schematics of the circuit, so I could see the wiring part?

So data storage should to Flash memory should be done with microcontroller such as MSP430? Because a member from another forum told me that I could use EEPROM or NOR flash such as that one and connect it do CC2541 directly by implementing SPI driver, so MSP430 supposedly wouldn't be needed in that case?

0 DavidL over 10 years ago in reply to vix3c

TI__Mastermind 25045 points

Hi,

vix3c said:
Would it be possible to get datasheet/schematics of the circuit, so I could see the wiring part?

Please contact SVTronics (http://www.svtronics.com) for the schematics of the watch.

vix3c said:
So data storage should to Flash memory should be done with microcontroller such as MSP430? Because a member from another forum told me that I could use EEPROM or NOR flash such as that one and connect it do CC2541 directly by implementing SPI driver, so MSP430 supposedly wouldn't be needed in that case?

Yes, that could work.

Regards,

David

0 vix3c over 10 years ago in reply to DavidL

Intellectual 430 points

Thank you for the tip, I have contacted them.

So would therefore the usage of MSP430 even have any advantages over CC2541? Is it also possible to attach any physical buttons to CC2541 for controlling the functions of firmware (e.g. "send data to phone", "standby mode" etc.)? Where may I find any documentation and tutorials on implementation of SPI driver for CC2541 and how to use it to write/read data on EEPROM/NOR?

0 Ahmad_Rashed over 10 years ago in reply to vix3c

TI__Genius 13567 points

Hello,

You would probably want to go with the CC2640 instead. It supports BLE, is much lower power than the CC2541, contains a faster MCU (Cortex-M3), and there is a tutorial for adding SPI to any of the TI BLE software examples.

processors.wiki.ti.com/.../Cc2640_Adding_a_UART_or_SPI_driver_to_a_Sample_Project

In addition, TI recently released a CC2650 Launchpad that allows you to easily prototype and program your wireless heart monitor.

www.ti.com/.../LAUNCHXL-CC2650

Any BLE software you write for the CC2650 is binary compatible with the CC2640. Hope this helps!

Regards,
Ahmad

0 DavidL over 10 years ago in reply to Ahmad_Rashed

TI__Mastermind 25045 points

Hi,

As Ahmad mentioned, the CC2640 might be a better option (especially because of the higher performance). In regards to your other CC2541 questions, I would recommend posting them in the Bluetooth® Smart Forum.

Best regards,

David

0 vix3c over 10 years ago in reply to DavidL

Intellectual 430 points

Thank you both for the answers, CC2640 certainly looks like a wiser choice. As you may see on the Wireless Heart Monitor with Bluetooth Low Energy page, there is already firmware provided for CC2541. I was wondering to how extend is the code compatible between them? Could I simply copy/paste it or would it require adjustments? And which one?

Is the learning curve for programming MSP430 (or other TI microcontrollers) the same for SoC such as CC2640?

0 Ahmad_Rashed over 10 years ago in reply to vix3c

TI__Genius 13567 points

BLE APIs are the same. The amount of porting effort will vary depending on the complexity of your project. The same reference projects from the CC254x SDK were ported to the CC2640 and are available in the SDK.

I highly recommend this FAQ that can be found in the BLE forum.
e2e.ti.com/.../404236

0 DavidL over 10 years ago in reply to vix3c

TI__Mastermind 25045 points

Hi vix3c,

Again, I would recommend asking this question to BLE experts in the Bluetooth® Smart Forum.

Best regards,

David

0 DavidL over 10 years ago in reply to DavidL

TI__Mastermind 25045 points

I'm going to close the thread due to inactivity, but please post back if you have more information to re-open the thread.

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Store data from ADS1293 and transfer it to Android device over BT