Am I going mad?

clive · Joined: 17 Nov 2007 Posts: 2

Please help me with a problem I have using Timers.

When I use the following code and simulate it,
I get the right value in variable A (i.e A=1001)

$regfile="reg51.dat"
$crystal=12000000
$noinit
disable interrupts

Dim A as word

Set Tmod.0
Reset Tmod.1

TL0=1
TH0=0

Start Timer0

Waitms 1

A = Counter0

End

But when I use the following code as recomended in the help
file of Bascom, I get a hopelessly incorrect value (A=65535)

$regfile="reg51.dat"
$crystal=12000000
$noinit
disable interrupts

Dim A as word
Config Timer0=counter , Gate=Internal , Mode=1

Load Timer0 , 1
Start Timer0

Waitms 1

A = Counter0

End

What am I doing wrong?

Gianni · Joined: 09 Jul 2004 Posts: 61 Location: Italy

Please help me with a problem I have using Timers.

When I use the following code and simulate it,
I get the right value in variable A (i.e A=1001)

$regfile="reg51.dat"
$crystal=12000000
$noinit
disable interrupts

Dim A as word

Set Tmod.0
Reset Tmod.1
You can't do that! Tmod is not bit addressable

TL0=1
TH0=0

Start Timer0

Waitms 1

A = Counter0

End

But when I use the following code as recomended in the help
file of Bascom, I get a hopelessly incorrect value (A=65535)

$regfile="reg51.dat"
$crystal=12000000
$noinit
disable interrupts

Dim A as word
Config Timer0=counter , Gate=Internal , Mode=1
I suppose this can't works with simulator
Timer0=counter means you use an external clock at T0 pin
You should use
Config Timer0=timer , Gate=Internal , Mode=1

Load Timer0 , 1
Load works for autoreload mode only
You must use Counter=1

Start Timer0

Waitms 1

A = Counter0

End

What am I doing wrong?

clive · Joined: 17 Nov 2007 Posts: 2

Thank you, now I know where I went wrong.