David <lists <at> edeca.net> writes:

>=20
> All,
>=20
> I have just started using a 12F617 instead of the larger pin count 18F =20
> parts.  I am using HiTech in Lite mode.
>=20
> The code is here: http://pastebin.com/nrQDC224 with the compiled =20
> version here: http://pastebin.com/kibNLyZx
>=20
> In main(), I get to line 170 (0x7F9 in the compiled version) and the =20
> status LED is lit.  I can see this in MPLAB simulator and on the =20
> target board (if I use a while(1) afterward so it stalls).  However, a =20
> few cycles later we get back to line 38 (0x765 in ASM) and for some =20
> reason the entire GPIO port is reset to 0x00.  This happens both in =20
> the simulator and in the real hardware.
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> I have tried a number of different code variations for the same thing, =20
> which all compile to the same.  However, in all cases the GPIO port =20
> gets set to 0x00.
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> Is there anything I am doing wrong in the code that means the GPIO =20
> port is reset?
>=20
> David

Hi David,=20
First, disclaimer: I do not use PIC12F617 nor HITECH-C.=20
Looking at your code, couple notes:=20
1.  STATUS_LED should not flash, once set to 1 it should stay there (line 1=
70).
 There is no explicit code to set it to 0.
2. on line 38: you set GPIO1 to 1.  The GPIO port is read-modify-right.  So=
 that
should set only GPIO1 to 1, the rest of the port should be 0 (specifically,=
 RA2
should be 0 since all other port bits are inputs).
3. line 38 is executed from within while(1) when you call IR_Pulse() on lin=
e 160.
4. Maybe use a shadow variable for the port, then set/clear bits in the var=
iable
and set GPIO =3D shadow variable. =20

my $0.02
Sergey Dryga
http://beaglerobotics.com







--=20
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