Timers

el98650 · ‎2003-03-31

Posted on March 31, 2003 at 12:43

Timers

el98650 · ‎2003-03-31

Posted on March 31, 2003 at 11:16

Hello again,

i have some questions regarding the increment of the timers. Is the Timer register incremented once a cycle?

To generate a precies Tick every 50 ms with a clock at 20MHz is the required reload value 0x03E8?(20Mhz*50ms)?

Thanks

Vasilios

el98650 · ‎2003-03-31

Posted on March 31, 2003 at 11:50

OK here is the code bit which confused me:

/ * this. Timeout is set to 5 msec assuming a 20 MHz bus

/// ---------------------------------------------------------------

/// Configuration of CC1 timer 0:

/// ---------------------------------------------------------------

/// - timer 0 works in timer mode

/// - prescaler factor is 8

/// - timer 0 run bit is set

T01CON = 0x0000; // load CAPCOM1 timer 0 and timer 1

T0 = 0xCF2C; // load CAPCOM1 timer 0 register

T0REL = 0xCF2C; // load CAPCOM1 timer 0 reload register

According to the c167 users manual (is there any better document around?) the resolution with a 20Mhz clock is 400ns, so the loaded value would generate a 21ms delay wouldn't it?

Thanks

(The Value i think i need for 50ms is a prescaler of 16 and a register value of 0xF424) ...

el98650 · ‎2003-03-31

Posted on March 31, 2003 at 12:43

AHEM,

counting upwards....

Next time i make sure i read better before asking..

Vasilios