HeMon Heart Rate Monitor source code

[baboo2002]

hemon heart rate

Hello,

I wish to build the HeMon circuit which the schematic is located here: **broken link removed**. I'm having problems understanding the design because of the style in which the author has used. Chiefly, the leads on the resistor network, RN1, marked LED SEG A-G, do they connect to all 3 seven segment displays? For example, LED SEG A of RN1 connects to Pin 4 of Display 1, 2, and 3.

I've got a few more questions but I'll ask them one at a time to reduce confusion. Sadly, I'm easily confused

 

[laktronics]

hemon circuit

Hi,
Yes, the resistors are connected to corresponding pins of all displays to limit the segment current when on. This is possible because the displays are time multiplexed and only one display is turned on at a time using the transistor connected to the common cathode of each display.
The difficult portion of the project as I see it,may be to generate the heart beat pulses and you should wire up this portion first and test to see if you are getting proper pulses. Once the pulses are got, it is a simple job to count the pulses per minute in a micro controller and display the value if you are good at micro controllers. It is better to wire up the the pulse generation portion on a daughter board and mount the remaining circuit on a separate board and develop the pulse counting and display software in parallel if you have got more members to do the job. In this way even if you need to modify the pulse generation portion, only a small pcb need to be changed.
Regards,
Laktronics

 

[baboo2002]

heart rate monitor circuit

Thanks for the reply Laktronics. Very helpful.

I have another question, the schematic displays that I need to install a 4mHz crystal on pins 15 and 16 of the microcontroller. I've obtained the a 4mHz PIC 16F84A, would I still need to install the crystal?

 

[Siniša]

hemon project heart rate

4MHz PIC means it can work with clock up to 4MHz. You need crystal for PIC to work. I think you are probably not aware that you need to program this chip as well in order to be functional. For that you would need to download code from same web site, you will need software for converting source assembler file (.asm extension) to machine code (downloadable free from Microchip.com) and you will need to buy/build/borrow PIC programmer that supports this chip. One of thousands of sources could be MeLabs.com . Search EDA for this under microcontrollers.
Programming will require some reading and familiarizing yourself with MCU, hardware and software.

 

[baboo2002]

hemon schematic

4MHz PIC means it can work with clock up to 4MHz. You need crystal for PIC to work. I think you are probably not aware that you need to program this chip as well in order to be functional. For that you would need to download code from same web site, you will need software for converting source assembler file (.asm extension) to machine code (downloadable free from Microchip.com) and you will need to buy/build/borrow PIC programmer that supports this chip. One of thousands of sources could be MeLabs.com . Search EDA for this under microcontrollers.
Programming will require some reading and familiarizing yourself with MCU, hardware and software.

I was aware of the fact it must programmed but I did not know where to get the software until now. Thanks again everyone.

 

[baboo2002]

hemon heart rate monitor

Hello again,

Ok, so now I've compiled the source code into a .COD, .err, .HEX, and .lst file. I'm in the process of receiving the components for a programmer with a DB25 connector and I was just wondering, does MPLAB work with any programmer? Do I have to acquire a programmer under the "Programmer" drop down menu?

Thanks.

 

[metallics2000]

heartbeat hemon

Hi all,

I have been doing the heartbeat sensor portion of this project and seemed to got it to work; however, what does this voltage divider with capcitor do(R2, R10, and C7)? This is right before the the first op amp.

To me it seems like the voltage divider is biasing the opamp and the capacitor is to block DC. But it also looks like its a highpass filter since the ouput to the opamp is taken after the capacitor. If it is ,why would it be a high pass filter instead of a lowpass filter? Or is this a combination of a highpass filter and does biasing for the opamp also? Any thoughts on this would be appreciated.

Thanks

 

[pranam77]

pic projects heartrate

Hello again,
Ok, so now I've compiled the source code into a .COD, .err, .HEX, and .lst file. I'm in the process of receiving the components for a programmer with a DB25 connector and I was just wondering, does MPLAB work with any programmer? Do I have to acquire a programmer under the "Programmer" drop down menu?
Thanks.

MPLAB will work only with PicKit2 and its compatible/ Clones which operate on the USB port. For the programmer you are refreing with a DB25 prt, use the programmming software which is given witth the programmer. You may also try various JDM programmers available on the net which works with the serial port.

 

[buffster88]

Re: HeMon Heart Rate Monitor

Hello!

Iv've tried building this circuit and I keep getting '141' on the display or very high or low reading. It only sometimes gives the correct otuput. what could be the problem?

 

[kanuj_mit]

HeMon Heart Rate Monitor

i m also done with the hardware. I am new to PICs. could you pls gimme the program for the PIC16f84A?

 

[pranam77]

Re: HeMon Heart Rate Monitor

i m also done with the hardware. I am new to PICs. could you pls gimme the program for the PIC16f84A?

You may download the complete project with source code at the given link below.
Hope it helps you. Cheers
**broken link removed**

 

[eng.BAHAA]

HeMon Heart Rate Monitor

hi all
can i replace red LED (high intinsty 1000 mcd) to laser LED?
what is the effect of it?
and what is the kind of ORP12?
Thanks