Math Processor Unit Library

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+.TH idec 3  "December 27, 2024" "libmpu" "LibMPU Programmer's Manual"
+.SH NAME
+\fBidec\fP \- decrement
+.SH SYNOPSIS
+.nf
+.B #include <libmpu.h>
+.PP
+.BI "void idec( mpu_int *" c ", mpu_int *" a ", int " nb " );
+.fi
+.SH DESCRIPTION
+The \fBidec()\fP function performs the decrement operation (c = a \- 1) of the \fBa\fP operand.
+The result is placed at address \fBc\fP. The contents of the memory at address \fBa\fP remain
+unchanged, and the previous memory contents at \fBc\fP are lost. The \fBnb\fP parameter determines
+the size of operands (in bytes) located at addresses \fBc\fP, \fBa\fP.
+.PP
+The function affects the flags \fBA\fP, \fBO\fP, \fBP\fP, \fBS\fP, \fBZ\fP.
+.PP
+The \fBC\fP flag does not change (the previous value is retained). The \fBP\fP flag is set only
+when the flag is set only when the size of the \fBc\fP, \fBa\fP operands is one or two bytes
+(\fBnb\fP == 1 || \fBnb\fP == 2).
+.sp
+.SH SEE ALSO
+.BR iadd(3),
+.BR isub(3),
+.BR iadc(3),
+.BR isbb(3),
+.BR ishl(3),
+.BR ishr(3),
+.BR isal(3),
+.BR isar(3),
+.BR irol(3),
+.BR iror(3),
+.BR ircl(3),
+.BR ircr(3),
+.BR ishln(3),
+.BR ishrn(3),
+.BR isaln(3),
+.BR isarn(3),
+.BR iroln(3),
+.BR irorn(3),
+.BR ircln(3),
+.BR ircrn(3),
+.BR ineg(3),
+.BR inot(3),
+.BR iand(3),
+.BR itest(3),
+.BR icmp(3),
+.BR ior(3),
+.BR ixor(3),
+.BR iinc(3),
+.BR ixchg(3),
+.BR icpy(3),
+.BR icvt(3),
+.BR imul(3),
+.BR ismul(3),
+.BR idiv(3),
+.BR isdiv(3),
+.BR iatoi(3),
+.BR iatoui(3),
+.BR iitoa(3),
+.BR iuitoa(3).