TC1796
System Units (Vol. 1 of 2)
Peripheral Control Processor (PCP)
User’s Manual
11-104
V2.0, 2007-07
PCP, V2.0
11.11.36 SUB, 32-Bit Subtract
This section describes the SUB instructions of the PCP.
SUB
Syntax
SUB Rb, Ra, cc_A
Description
If the condition CONDCA is true, then subtract the contents of
register Ra from the contents of register Rb; place the result
in Rb. If CONDCA is false, no operation is performed.
Operation
if (CONDCA = True) then R[b] = R[b] - R[a] else NOP
Flags
N, Z, V, C
SUB.I
Syntax
SUB.I Ra, #imm6
Description
Subtract the zero-extended immediate value imm6 from the
contents of register Ra; place the result in Ra.
Operation
R[a] = R[a] - zero_ext(imm6)
Flags
N, Z, V, C
SUB.F
Syntax
SUB.F Rb, [Ra], Size
Description
Subtract the zero-extended contents of the address location
specified by the contents of register Ra from the contents of
register Rb; place the result in Rb.
Operation
R[b] = R[b] - zero_ext(FPI[R[a]])
Flags
N, Z, V, C
SUB.PI
Syntax
SUB.PI Ra, [#offset6]
Description
Subtract the contents of the PRAM location specified by the
addition of contents of the PRAM Data Pointer, shifted left by
six bits, and the zero-extended 6-bit value offset6 from the
contents of register Ra; place the result in Ra.
Operation
R[a] = R[a] - PRAM[(DPTR<<6) + zero_ext(#offset6)]
Flags
N, Z, V, C
