FP_ASCII_TO_DEC

ASCII -> decimal conversion

This FP instruction converts the hexadecimal ASCII codes beginning at s_Start to decimal numbers if the trigger EN is TRUE. n_Chars specifies the number of bytes to be converted.The result is stored in d.

Parameters

Input

s_Start (WORD, INT, UINT): Starting address
n_Chars (WORD, INT, UINT): Number of bytes

Output

d (INT, DINT, UINT, UDINT): Converted bytes

Remarks

ASCII HEX codes to express decimal characters:

Decimal characters	ASCII HEX code
SPACE+-0123456789	16#2016#2B16#2D16#3016#3116#3216#3316#3416#3516#3616#3716#3816#39

Error flags

sys_bIsOperationErrorHold (turns to TRUE and remains TRUE)

if the area specified using the index modifier exceeds the limit.
if the number of bytes specified by n_Chars is greater than the area specified by d
if the conversion result is greater than the data area specified by d
if ASCII characters other than 0–9, signs (+, –) or space is specified

sys_bIsOperationErrorNonHold (turns to TRUE for one scan)

if the area specified using the index modifier exceeds the limit.
if the number of bytes specified by n_Chars is greater than the area specified by d
if the conversion result is greater than the data area specified by d
if ASCII characters other than 0–9, signs (+, –) or space is specified

Example 32-bit data, unsigned

	Offset	ASCII codes	Dec. equivalent			Offset	Converted decimal characters	Decimal figure
s_Start	0	16#3620	6	Þ	d	0	16#FF9C	65436
	1	16#3435	45		d	1
	2	16#3633	63
n_Chars	0	16#0006

Example 32-bit data, signed

	Offset	ASCII codes	Dec. equivalent			Offset	Converted decimal characters	Decimal figure
s_Start	0	16#2020		Þ	d	0	16#FF9C	-100
	1	16#312D	1 -		d	1
	2	16#3030	00
n_Chars	0	16#000A

Example 32-bit data, unsigned

	Offset	ASCII codes	Dec. equivalent			Offset	Converted decimal characters	Decimal figure
s_Start	0	16#3234	24	Þ	d	0	16#FF9C	4294967196
	1	16#3439	49			1	16#FFFF
	2	16#3639	69			2
	3	16#3137	17
	4	16#3639	69
n_Chars	0	16#000A

Example 32-bit data, signed

	Offset	ASCII codes	Dec. equivalent			Offset	Converted decimal characters	Decimal figure
s_Start	0	16#2020		Þ	d	0	16#FF9C	-100
	1	16#2020			d	1	16#FFFF
	2	16#2020
	3	16#312D
	4	16#3030
n_Chars	0	16#000A

Example

POU header

All input and output variables used for programming this function have been declared in the POU header. The same POU header is used for all programming languages.

	VAR
		bStart: BOOL:=FALSE;
			(*activates the function*)
		wASCII_input: WORD:=16#3031;
		iConversion_result: INT:=0;
	END_VAR

POU body

When the variable bStart is set to TRUE, the function is carried out.

LD body

BODY
    WORKSPACE
        NETWORK_LIST_TYPE := NWTYPELD ;
        ACTIVE_NETWORK := 0 ;
    END_WORKSPACE
    NET_WORK
        NETWORK_TYPE := NWTYPELD ;
        NETWORK_LABEL :=  ;
        NETWORK_TITLE :=  ;
        NETWORK_HEIGHT := 7 ;
        NETWORK_BODY
B(B_CONTACT,,bStart,5,3,7,5,);
B(B_VARIN,,wASCII_input,11,4,13,6,);
B(B_VARIN,,2,11,5,13,7,);
B(B_VAROUT,,iConversion_result,23,4,25,6,);
B(B_F,FP_ASCII_TO_DEC!,,13,2,23,7,,?DEN?Ds_Start?Dn_Chars?AENO?Cd);
L(1,4,5,4);
L(7,4,13,4);
L(1,0,1,7);
        END_NETWORK_BODY
    END_NET_WORK
END_BODY

ST body

IF (bStart) then
    FP_ASCII_TO_DEC(s_Start := wASCII_input, 
                    n_Chars := 2, 
                    d => iConversion_result);
END_IF;