Again I call for help.
1. The SLAA274 schematic on the last page...
has an led and two switches. I cannot find where in the code this led
is activated. Can anyone point this out to me? Also, the two
switches...is their purpose related to delaying power for circuit
timing purposes?
2. Regarding the NPN & PNP LED transistor circuits...there are
differences, mainly resistors, between the main schematic and the
breakout schematics. Has anyone noticed this and which one is right?
3. Regarding the oscillator shown on the schematic...it shows no
capacitors. The TI oximeter code "oximeter_ext_probe_1.c"...sets the
oscillator capacitance at 14pf (FLL_CTL0 = DCOPLUS + XCAP14PF). The
oscillator I use is specified at 12.5 pf. Do I need to add
capacitors...or is the difference negligible?
Any help, as always, is appreciated.
Mike
SLAA274 TI Pulse Oximeter
Started by ●February 15, 2009
Reply by ●March 14, 20092009-03-14
Reply by ●March 14, 20092009-03-14
Hello .., I am also doing the same project and not had success with it.
The oximeter is dead, dont work. Some of you have any tips for me?
Thank you very much.
--- In m..., anju latha wrote:
>
> hi
> i am also doing same project
>
> are u completed the project with correct results
>
> anju
>
>
The oximeter is dead, dont work. Some of you have any tips for me?
Thank you very much.
--- In m..., anju latha wrote:
>
> hi
> i am also doing same project
>
> are u completed the project with correct results
>
> anju
>
>
Reply by ●March 18, 20092009-03-18
I have been working on mine for about 4 months on and off. My unit still
doesn't work, but I have hopes...perhaps by this weekend.
Here is what I think I have found so far [remember, my unit doesnt work so right from wrong is subjective]...
The TI Code has at least one error - I think...I dont remmember all the details...but there is an assignment made to port 3 which I believe should be port 2.
The TI schematic has some errors...the T1 & T2 base and emitter resistors do not agree with the breakout schematics in the middle of SLAA274. I think the breakout schematics are right.
I think Pins 1 & 52 should come right off VCC and not go through the R4 resistor shown on the schematic.
The VCC capacitor (C3) shown [on schematic] feeding MSP pin 80 is not big enough ...there is an obscure reference to timing requirements for Pin 80 in the MSP430 data sheet. I replaced C3 with a 10 Uf.
I tell you more as I progress.
--- In m..., "versiani25" wrote:
>
> Hello .., I am also doing the same project and not had success with it.
> The oximeter is dead, dont work. Some of you have any tips for me?
> Thank you very much.
>
>
> --- In m..., anju latha wrote:
> >
> > hi
> > i am also doing same project
> >
> > are u completed the project with correct results
> >
> >
> >
> > anju
> >
> >
> >
> >
>
>
>
>
>
Here is what I think I have found so far [remember, my unit doesnt work so right from wrong is subjective]...
The TI Code has at least one error - I think...I dont remmember all the details...but there is an assignment made to port 3 which I believe should be port 2.
The TI schematic has some errors...the T1 & T2 base and emitter resistors do not agree with the breakout schematics in the middle of SLAA274. I think the breakout schematics are right.
I think Pins 1 & 52 should come right off VCC and not go through the R4 resistor shown on the schematic.
The VCC capacitor (C3) shown [on schematic] feeding MSP pin 80 is not big enough ...there is an obscure reference to timing requirements for Pin 80 in the MSP430 data sheet. I replaced C3 with a 10 Uf.
I tell you more as I progress.
--- In m..., "versiani25" wrote:
>
> Hello .., I am also doing the same project and not had success with it.
> The oximeter is dead, dont work. Some of you have any tips for me?
> Thank you very much.
>
>
> --- In m..., anju latha wrote:
> >
> > hi
> > i am also doing same project
> >
> > are u completed the project with correct results
> >
> >
> >
> > anju
> >
> >
> >
> >
>
>
>
>
>
Reply by ●July 22, 20092009-07-22
Hi all, i'm also starting with the project, but i got some doubts, when
i'm compiling the code i can't see if it works fine, after the IAR
debugger enters the infinite loop in main it gets stuck in the line when read
the variable log_heart_signal_sample_counter, i tough it might be the division
by 0, because in the watch that's it's value, but even i change
it's value in the watch or i make a simple assignation (float
d=log_heart_signal_sample_counter; ) the debugger can't pass this line (no
errors just "take an infinite time executing this instruction")
Best Regards.
PS. Sorry for my bad english
--- In m..., "steam_y" wrote:
>
> I have been working on mine for about 4 months on and off. My unit still doesn't work, but I have hopes...perhaps by this weekend.
>
> Here is what I think I have found so far [remember, my unit doesnt work so right from wrong is subjective]...
>
> The TI Code has at least one error - I think...I dont remmember all the details...but there is an assignment made to port 3 which I believe should be port 2.
>
> The TI schematic has some errors...the T1 & T2 base and emitter resistors do not agree with the breakout schematics in the middle of SLAA274. I think the breakout schematics are right.
>
> I think Pins 1 & 52 should come right off VCC and not go through the R4 resistor shown on the schematic.
>
> The VCC capacitor (C3) shown [on schematic] feeding MSP pin 80 is not big enough ...there is an obscure reference to timing requirements for Pin 80 in the MSP430 data sheet. I replaced C3 with a 10 Uf.
>
>
> I tell you more as I progress.
>
>
>
> --- In m..., "versiani25" wrote:
> >
> > Hello .., I am also doing the same project and not had success with it.
> > The oximeter is dead, dont work. Some of you have any tips for me?
> > Thank you very much.
> >
> >
> > --- In m..., anju latha wrote:
> > >
> > > hi
> > > i am also doing same project
> > >
> > > are u completed the project with correct results
> > >
> > >
> > >
> > > anju
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
Best Regards.
PS. Sorry for my bad english
--- In m..., "steam_y" wrote:
>
> I have been working on mine for about 4 months on and off. My unit still doesn't work, but I have hopes...perhaps by this weekend.
>
> Here is what I think I have found so far [remember, my unit doesnt work so right from wrong is subjective]...
>
> The TI Code has at least one error - I think...I dont remmember all the details...but there is an assignment made to port 3 which I believe should be port 2.
>
> The TI schematic has some errors...the T1 & T2 base and emitter resistors do not agree with the breakout schematics in the middle of SLAA274. I think the breakout schematics are right.
>
> I think Pins 1 & 52 should come right off VCC and not go through the R4 resistor shown on the schematic.
>
> The VCC capacitor (C3) shown [on schematic] feeding MSP pin 80 is not big enough ...there is an obscure reference to timing requirements for Pin 80 in the MSP430 data sheet. I replaced C3 with a 10 Uf.
>
>
> I tell you more as I progress.
>
>
>
> --- In m..., "versiani25" wrote:
> >
> > Hello .., I am also doing the same project and not had success with it.
> > The oximeter is dead, dont work. Some of you have any tips for me?
> > Thank you very much.
> >
> >
> > --- In m..., anju latha wrote:
> > >
> > > hi
> > > i am also doing same project
> > >
> > > are u completed the project with correct results
> > >
> > >
> > >
> > > anju
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
