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In a SPI slave using the PIC Hardware spi peripheral, is it possible to find out if SS went low for the current byte or was already low to begin with before the current byte was transferred, without h ...

A SPI slave I am using (a FRAM device) requires me to hold the SS line low for multiple bytes in the same transaction (the first byte in a transaction is the command byte followed by context dependent ...

Obvious question is how fast the data is being sent, and whether there is any delay between operating the select, and the data being sent. Given the way the code is written, there is a huge delay be ...

I am coding a SPI slave using a PIC16F877A and need to be aware when the SS line goes from high (idle) to low (active) as information from the master is framed as a stream of bytes with the leading by ...

@collink : I am interested in seeing the project that make the compiler behave so.

Could I have a look at it please?

Well?

:-)

Just wondering.... 0.002% == 20ppm
Have you checked the accuracy of your clock? Most likely your crystal will have a larger frequency spread over your application's operating temperature range.
...

The problem is that the optimiser sees the second jump and says 'this is a waste of time'....

In that case why does this work correctly:

#inline
void delay4(void) {
#asm
...

The nearest I can think of, would be (as a standalone function):

#inline
void delay4(void) {
#asm
GOTO inner1
inner1:
GOTO inner2
inner2:
#endasm
}

Or jus ...

What compiler version?.

4.107

You comment on their not being routes to some parts of the code. Yet looking through the code, I can see routes to every line.

So 'no', I don't think your ana ...

It's not about the inaccuracy.

It's about the spurious check making the delay inaccurate.

Had those two lines not being there - it would have been 100% accurate.

( why handcode a delay - as I ...

Start exploring MPLAB. Go to the View menu. Bring up the Disassembly
Listing window. Put your breakpoints in there. Explore the program.

That's it. Thanks again.

Read the Help file.

I ...

For delays less than 153uS, CCS C generates the delay inline yeilding a 100% accurate delay.

Above 154uS ( and < 256uS ), CCS C uses a function call.

This function has a spurious check that i ...

Look it up in the PIC data sheet. For example, for the 18F452, look in
this section:

TABLE 20-2: PIC18FXXX INSTRUCTION SET

It lists the number of cycles used by each type of instruction.
Just ...

MPLAB Stopwatch can count instruction cycles.
http://www.ccsinfo.com/forum/viewtopic.php?t=38351

One more question - how do I do the same *but* between two lines in assembly generated by CCS?

F ...