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Topic: NilRTOS - A Fast Tiny Preemptive RTOS (Read 18668 times) previous topic - next topic

fat16lib

#15
Jan 25, 2013, 09:47 pm Last Edit: Jan 25, 2013, 09:50 pm by fat16lib Reason: 1
It may be a problem with Serial.read().  nilFifoDataLogger is the only example with Serial.read().

I have tried many Arduino boards and two Windows 7 computers with no problem.

Load the nilTemplate1 example and put the following at the beginning of loop() like this.

Code: [Select]

void loop() {
 int c = Serial.read();
 if (c < 0) return;
 Serial.print((char)c);
 return;

Run the example and type one or two characters into the serial monitor and see if they are echoed.

Also run nilFifoDataLogger  with no SD card and see if this prints:
Quote

type any character to begin
SD problem
SD errorCode: 0X1,0X0


pito

#16
Jan 25, 2013, 10:05 pm Last Edit: Jan 25, 2013, 10:09 pm by pito Reason: 1
Quote
Also run nilFifoDataLogger  with no SD card and see if this prints:
Quote
type any character to begin
SD problem
SD errorCode: 0X1,0X0

Code: [Select]
type any character to begin
SD problem
SD errorCode: 0X1,0X0


Yes they are echoed (after pushing Send):
Code: [Select]
33
54
pito
Q

pito

#17
Jan 25, 2013, 10:19 pm Last Edit: Jan 25, 2013, 10:25 pm by pito Reason: 1
:)
Code: [Select]

type any character to begin
type any character to end
Done
Unused Stack: 141 342

** overrun errors **



with:
Code: [Select]

// SD chip select pin.
const uint8_t sdChipSelect = 10; //SS;

fat16lib

pito,

Could you put a continue statement in thread 1 like this so no data is taken.

Code: [Select]

  while (1) {
    // Sleep until time for next data point
    nilThdSleep(intervalTicks);
    continue;


Let me know what happens.

pito

#19
Jan 25, 2013, 11:04 pm Last Edit: Jan 25, 2013, 11:37 pm by pito Reason: 1
Code: [Select]
type any character to begin
type any character to end
Done
Unused Stack: 141 445

data.csv is 0kB

No idea what is the issue, with "continue" it always works, with "//continue" it sometimes works, sometimes does not.

fat16lib

#20
Jan 25, 2013, 11:13 pm Last Edit: Jan 25, 2013, 11:19 pm by fat16lib Reason: 1
How was this run?  Was any data recorded?
Quote

type any character to begin
type any character to end
Done
Unused Stack: 141 342

** overrun errors **


with:
Code:

// SD chip select pin.
const uint8_t sdChipSelect = 10; //SS;


The output is from the old example.  It should look like this from today's pito.zip file.
Quote

type any character to begin
type any character to end
Done
Maximum SD write latency: 3748 usec
Unused Stack: 57 407

pito

Yes, when ran the old one I got csv data (100-200kB).

I cannot get it working with the new version yet.. Still the same issue, with =10 or =SS.. It works with "continue;" only:

Code: [Select]
type any character to begin
type any character to end
Done
Maximum SD write latency: 0 usec
Unused Stack: 57 480

No idea what to do in order to get it working..

pito

With new one I get now this
Code: [Select]
type any character to begin
type any character to end
Done
Maximum SD write latency: 48548 usec
Unused Stack: 141 372


with:
   
Code: [Select]
// Read ADC data.
    p->value = 555; //analogRead(0);

Strange..

pito

#23
Jan 26, 2013, 12:11 am Last Edit: Jan 26, 2013, 12:25 am by pito Reason: 1
It seems this does the trick (the original example, 115k2) :

Code: [Select]
void setup() {

  Serial.begin(115200);
 
  analogReference(INTERNAL);

:smiley-roll-sweat:

Code: [Select]
type any character to begin
type any character to end
Done
Maximum SD write latency: 19736 usec
Unused Stack: 57 456


Code: [Select]
NA 252 0
1024 41 0
1024 47 0
1024 48 0
1024 46 0
1024 45 0
1024 36 0
1024 33 0

fat16lib

I need to think about this.  I don't touch the ADC stuff.

I must go out with my wife now.

pito

Another issue I've found - I have to use:
Code: [Select]
struct FifoItem_t {
  uint16_t usec;        // Low 16-bit of time in usec.
  uint16_t value;  // ADC value.
  uint8_t error;   // Overrun count since last point.
};

otherwise the adc value read is not correctly passed to p->value. It seems our compiler has got a problem with passing values to bitfields ..

fat16lib

#26
Jan 26, 2013, 03:56 am Last Edit: Jan 26, 2013, 04:55 am by fat16lib Reason: 1
I don't understand.  I store this counter in thread 1
Code: [Select]

 //  p->value = analogRead(0);
    p->value = nr;
    nr = nr < 1023 ? nr + 1: 0;

and the correct result is written to the SD.  The bit field works fine.  I ran it for many cycles of 0 - 1023.

Why can't I reproduce your results?

Edit: I now can show that only 8-bit of the ADC value get stored even though the counter works.

Edit: I got rid of the bit fields and now the ADC values in the file match a fixed voltage applied to pin A0.

pito

#27
Jan 26, 2013, 07:52 am Last Edit: Jan 26, 2013, 11:51 am by pito Reason: 1
.. you may see for example (when p->value is a bitfield):
Code: [Select]
p->value = 1023;      //this works
p->value = analogRead(0); //this does not work, only 8bits passed
p->value = temp;      //this does not work, only 8bits passed

PS: now it seems to me all above issues I saw here were caused by the bitfield issue..

fat16lib

pito,

Do you still need the call to analogReference() after changing FifoItem_t?

I really would like to get to the bottom of why you need the analogReference() call.  All it does is set the global analog_reference.  My experience has been that things like this are a symptom of a nasty bug.

Code: [Select]

uint8_t analog_reference = DEFAULT;

void analogReference(uint8_t mode)
{
// can't actually set the register here because the default setting
// will connect AVCC and the AREF pin, which would cause a short if
// there's something connected to AREF.
analog_reference = mode;
}



I have more cases where bit fields work and a lot where they don't.  Clearly they are to be avoided.

pito

I do not need analogreference when not using bitfields.

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