# C: Decimal to BCD

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## C: BCD to Decimal and Decimal to BCD

This scheme was supplied by Arne Bartels which allows BCD conversion in both directions. Add the following to the master source file:-

#include <math.h> #define Bcd2Dec(BcdNum) HornerScheme(BcdNum,0x10,10) #define Dec2Bcd(DecNum) HornerScheme(DecNum,10,0x10) UINT32 HornerScheme(UINT32 Num,UINT32 Divider,UINT32 Factor) { UINT32 Remainder=0,Quotient=0,Result=0; Remainder=Num%Divider; Quotient=Num/Divider; if(!(Quotient==0&&Remainder==0)) Result+=HornerScheme(Quotient,Divider,Factor)*Factor+Remainder; return Result; }

Then for each sub-gauge that requires a BCD conversion use the following syntax:-

Bcd2Dec(bcd_number) for BCD to decimal and Dec2Bcd(dec_number) for decimal to BCD conversions.

In order to send frequencies to the ADF radios, multiply the desired frequency by 10000:

float adf_freq = 0; adf_freq = 286.5; trigger_key_event(KEY_ADF_COMPLETE_SET, Dec2Bcd(adf_freq*10000));

In order to send frequencies to the COM or NAV radios, multiply the desired frequency by 100:

float com_freq = 0; com_freq = 122.875; trigger_key_event(KEY_COM_RADIO_SET, Dec2Bcd(com_freq * 100));//Change the event ID as needed for the NAV radio or the particular COM radio you wish to set