Post by thread:[PIC]: Help generating a 16 bit number

Hi everyone, I need to add ten numbers together and store the result in two locations N_hi and N_lo(a 16 bit number). I am sure there must be an easy way to do this. Can anyone please provide some code to achieve this. Many thanks Jason -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

G'day Jason, For each of the ten numbers, add them into the W register using an ADDWF instruction, but check the C flag of STATUS after each addition. If the C flag is set, increment the n_hi register. clrf n_hi clrw addwf n1, w skpnc incf n_hi addwf n2, w skpnc incf n_hi ... movwf n_lo Or if the numbers are in a series of locations, use FSR and INDF to loop through them. -- James Cameron spam_OUTquozlTakeThisOuTus.netrek.org http://quozl.netrek.org/ -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

; Multi-byte add routine. ; requires number of registers, start register address ; affects w, FSR / INDF and status ; result in N_hi and N_lo movlw number_of_registers movwf counter ; used to count how many successive registers to add together movlw start_register_address movwf fsr ; used FSR and INDF to address successive memory locations clrf N_hi ; start with zero in N_hi and N_lo clrf N_lo loop: movf INDF,w ; get latest byte to add in addwf N_lo,f ; add to low order byte skpnc ; test carry, if set, increment the hi order byte incf N_hi,f incf FSR,f decfsz counter ; if counter is >1 then repeat loop goto loop ; counter is zero, N_hi and N_lo contain reasult, w has changes tolast value, FSR has last pointer ; total routine size 13 words. ; execution time 4+ (10 x number of resisters) cycles Hope this helps, Regards, Kevin {Original Message removed}

homework? --- James Newton .....jamesnewtonKILLspam@spam@geocities.com 1-619-652-0593 -----Original Message----- From: pic microcontroller discussion list [PICLISTKILLspamMITVMA.MIT.EDU]On Behalf Of Jason Sent: Saturday, July 22, 2000 13:38 To: .....PICLISTKILLspam.....MITVMA.MIT.EDU Subject: [PIC]: Help generating a 16 bit number Hi everyone, I need to add ten numbers together and store the result in two locations N_hi and N_lo(a 16 bit number). I am sure there must be an easy way to do this. Can anyone please provide some code to achieve this. Many thanks Jason -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu>