Serin2 Timeout

[tazntex]

Would someone please explain in simple terms on how to use the Timeout with Serin2. The PBP manual says this:

"An optional Timeout and Label may be included to allow the program
to continue if a character is not received within a certain amount of time.
Timeout is specified in 1 millisecond units. If the serial input pin stays in
the idle state during the Timeout time, the program will exit the SERIN2
command and jump to Label."

Right now I am using this:

loop1:
SERIN2 serpin,16780,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
Return

Would I do something like this for timeout to be 10mS and to jump to label godosomething?
loop1:
SERIN2 serpin,16780,10, godosomething,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
Return

Also, is it also a good idea to use the flowpin?

Thanks Everyone

[mackrackit]

Your time out code looks correct.

The flow pin depends on your application. Myself, with the things I do, 9600 baud and lower, I have not had to use it.

[tazntex]

Thanks for the reply, is there anyway to set this up for 4800bps?

[mackrackit]

Look in the manual under SERIN2, it gives a formula and a sample table. Compare this to appendix A.

[skimask]

I'm beginning to think somebody doesn't have the little green book.
And if he/she does actually have the little green book, it hasn't been opened and/or read and/or studied much...

[tazntex]

Well, looking at SERIN2 and Appendix A, with the formula being (1000000/)-20
Appendix A states:
2400 Driven Inverted None 16780
9600** Driven Inverted None 16468
taking the formula and coming up with 188.3333333333etc...
I figure by looking at the examples 16780-188=16592.

SERIN2 serpin,16780,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
changed to this:
SERIN2 serpin,16592,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
So am I correct by saying 48000 bps would be 16592?

Thank you

[skimask]

Well, looking at SERIN2 and Appendix A, with the formula being (1000000/)-20
Appendix A states:
2400 Driven Inverted None 16780
9600** Driven Inverted None 16468
taking the formula and coming up with 188.3333333333etc...
I figure by looking at the examples 16780-188=16592.

SERIN2 serpin,16780,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
changed to this:
SERIN2 serpin,16592,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
So am I correct by saying 48000 bps would be 16592?

Thank you

That's what the PDF says (what about the little green book?).
A better explanation of the bits used in the SERIN2 mode number are in the SERIN2 section itself.

[mackrackit]

Well, looking at SERIN2 and Appendix A, with the formula being (1000000/)-20
Appendix A states:
2400 Driven Inverted None 16780
9600** Driven Inverted None 16468
taking the formula and coming up with 188.3333333333etc...
I figure by looking at the examples 16780-188=16592.

SERIN2 serpin,16780,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
changed to this:
SERIN2 serpin,16592,[wait(254),address1,address2,mydata1,mydata2,chk_su m]
So am I correct by saying 48000 bps would be 16592?

Thank you

Nope.

The numbers for the mode setting have been converted to decimal. We need to look at this from a binary point of view. If you do not have a handle on base2, things will be difficult with computers. The computer only understands two things, ON and OFF as in a switch, and most times with micros we can get away with thinking of 8 switches in a group, (or pins)

As you know with you PIC, the group of 8 is represented as bits 0 - 7.
With the SERIN2 modes we are talking about 16 switches, bits 0 - 15.

The table at SERIN2 in the manual gives the first 12 (0-12)bits of the mode and a formula to find this number.

Baud        0-12 bits  Binary
2400        396         0000110001100
4800        188         0000010111100

Now we have bits 13 - 15.
Bit 13 is for parity. 0=None 1=Even
Bit 14 is for conversion. 0=True 1=Inverted
Bit 15 is the Output. 0=Driven 1=Open

Go to appendix A and look at Mode Number 16780. We will build this from scratch.
Bit 15 is Driven = 0
Bit 14 is Inverted = 1
Bit 13 is No parity = 0
Take bits 0-12 from above 2400 baud and put it all together.
0100000110001100
and convert to Decimal = 16780

Now for Driven Inverted None 4800.
Bits 15 - 13
010
Bits 0-12 from above 4800
0000010111100
Put it together
0100000010111100
Convert to Decimal
16572 is the Mode Number for Driven Inverted None 4800 Baud.

I hope

Here is a page to do the conversions.
http://acc6.its.brooklyn.cuny.edu/~g.../nav2tool.html