I want to use a PCF8583 only as pulse-counter. That works...
For each pulse the countervalue (01h-03h) increase as expected. It works to set a alarmvalue (09h-0Bh) and get a Interrupt on Pin 7 when the countervalue is the same as the alarmvalue.
But what I don't get working ist to use the timeralarm.
I understand that I must
- set bit 0-2 in 08h > 0
- set bit 3 and bit 6 in 08h to 1
But I don't get an Interrupt in this configuration...
Is it possible at all to get an interrupt each 1, 100, 10.000 or 1.000.000 pulses in the counter-mode?
Must something set in 07h (timer)?
I hope all is great with you.
An alarm signal is generated when the contents of the alarm registers match bit-by-bit the contents of the involved counter registers.
Regarding the timer alarm, as the alarm that you described, it will be set when the timer value is the same than the alarm timer register (location 0Fh).
Besides of configuring the timer alarm, have you configured the timer register? The timer (location 07h) is enabled by setting the control and status register to XX0X X1XX.