The following ABAP types mapping table is valid for both SAP RFC and IDoc communication.
C
character[s]
CHAR, CLNT, CUKY, LANG, LCHR, UNIT
If the CHAR data is too long, the data will be truncated (no error thrown).
CHAR
N
NUMC, ACCP
STRING
I
INT4
s
INT2
b
INT1
F
FLOAT
P
CURR, DEC, QUAN
PACK
T
TIMS
D
DATS
XSTRING
RAWSTRING
X
RAW