procedure intrh is -- this is the interrupt handler pragma interrupt assembler local checkb4clr local checkb4 local dominute local dohour local b4clrcounter local docounter local sincr local dodisplay local notblank local writedata local theend bcf status_rp1 -- in bank 0 bcf status_rp0 -- ... -- on an interrupt, check the status of rb7 and rb4 -- to debounce, require 12 successive clicks on either -- pin to flip over to the next time. -- note: rb4 and rb7 are active low btfsc pin_b1 -- if rb7 is not being pushed goto checkb4clr -- check rb4 and clear rb7cnt incf rb7cnt,f -- otherwise, increment rb7cnt movlw 0x04 -- xor 4 with... xorwf rb7cnt,w -- ...rb7cnt btfsc status_z -- if rb7cnt == 0x04 goto dominute -- increment the minutes goto checkb4 -- else check on rb4 checkb4clr: clrf rb7cnt -- rb7 is not active; clear rb7cnt checkb4: btfsc pin_b0 -- if rb4 is not being pushed goto b4clrcounter -- do counter and clear rb4cnt incf rb4cnt,f -- otherwise, increment rb4cnt movlw 0x04 -- xor 4 with... xorwf rb4cnt,w -- ...rb4cnt btfsc status_z -- if rb4cnt == 0x04 goto dohour -- increment the hour goto docounter -- else do the counter dominute: -- don't clear rb7cnt until -- it goes inactive again -- one push == one minute -- start the display cycle over movlw 0x28 -- put 40 in... movwf sixtieths -- ...sixtieths clrf baz -- and clear baz -- now update minutes clrf seconds -- clear seconds incf minutes,f -- increment minutes movlw 0x3C -- xor 60 with... xorwf minutes,w -- minutes btfss status_z -- if minutes != 60 goto docounter -- go to the counter stuff clrf minutes -- clear the minutes dohour: -- start the display cycle over movlw 0x28 -- put 40 in... movwf sixtieths -- ...sixtieths clrf baz -- and clear baz incf hours,f -- now increment hours movlw 0x18 -- xor 24 with... xorwf hours,w -- hours btfsc status_z -- if hours == 24 clrf hours -- clear hours goto docounter -- don't clear rb4cnt -- one button push increments -- by exactly one hour b4clrcounter: clrf rb4cnt -- inactive r4b or fallthrough -- clear rb4cnt docounter: btfss intcon_t0if -- if the t0if isn't set goto theend -- we're done bcf intcon_t0if -- otherwise... movlw 0xFF -- reset clkset value movwf tmr0 -- put it in tmr0 incf sixtieths,f -- increment sixtieths movlw 0x32 -- xor 50 with... xorwf sixtieths,w -- ...sixtieths btfss status_z -- if sixtieths != 50 goto dodisplay -- just update the display -- else fall through into seconds movlw 0x01 -- if 1... subwf baz,f -- ...subtracted from baz btfsc status_c -- ...is not less than 0... goto sincr -- just increment seconds movlw 0x02 -- otherwise movwf baz -- baz = 2 incf writeleft,f -- each time baz resets, we swap -- the side on which we display -- the lone hours digit sincr: clrf sixtieths -- clear sixtieths incf seconds,f -- increment seconds movlw 0x3C -- xor 60 with... xorwf seconds,w -- ...seconds btfss status_z -- if seconds != 60 goto dodisplay -- just update the display -- else fall through into minutes clrf seconds -- clear seconds incf minutes,f -- increment minutes movlw 0x3C -- xor 60 with... xorwf minutes,w -- ...minutes btfss status_z -- if seconds != 60 goto dodisplay -- just update the display -- else fall through into hours clrf minutes -- clear minutes incf hours,f -- increment hours movlw 0x18 -- xor 24 with... xorwf hours,w -- ...hours btfsc status_z -- if hours == 24 clrf hours -- clear hours dodisplay: movf baz,f -- if baz... btfss status_z -- != 0 goto notblank -- we're writing something movlw 0xFF -- otherwise movwf port_b -- blank... movlw 0x0F -- ...the... movwf port_a -- ...display movf hours,w -- when we're blanking movwf tmphours -- update tmphours movf minutes,w -- and movwf tmpminutes -- tmpminutes goto theend -- and we're done notblank: movf tmphours,w -- load hours btfsc dispmin -- if dispmin movf tmpminutes,w -- load minutes instead bsf status_rp0 -- bank 1 movwf f628_eeaddr -- write address into eeaddr bsf f628_eecon1_rd -- read the data writedata: movf f628_eedata,w -- load data to write bcf status_rp0 -- bank 0 movwf port_b -- write to port_b andlw 0x0F -- cut off high nibble movwf port_a -- write to port_a btfsc dispmin -- if we're doing the minute display bsf pin_a6 -- turn on the left dot btfss dispmin -- if we're doing the hour display bsf pin_a7 -- turn on the right dot -- do PWM stuff movlw 0x4A -- load 74 into w addwf sixtieths,w -- add the sixtieths value bsf status_rp0 -- bank 1 movwf f628_eeaddr -- write this to the eeaddr bsf f628_eecon1_rd -- read the data movf f628_eedata,w -- load the data into w bcf status_rp0 -- bank 0 movwf ccpr1l -- this is the PWM value theend: bsf intcon_t0ie -- enable timer interrupt end assembler end procedure