Echelon Neuron - Manual (Page 214)

Mnemonic Operand Operation Description
SHL TOS = TOS <<1
TOS LSB = 0
C = 0
IP = IP+1 Logical shift TOS left by one.
SHLA C = TOS MSB
TOS = TOS << 1
TOS LSB = 0
IP = IP+1 Arithmetic shift TOS left by
one.
SHR TOS = TOS >>1
TOS MSB = 0
C = 0
IP = IP+1 Logical shift TOS right by one.
SHRA C = TOS LSB
TOS = TOS >> 1
TOS MSB = OLD TOS MSB
IP = IP+1 Arithmetic shift TOS right by
one.
SUB TOS,NEXT
TOS = TOS - [DSP--]
IF result < 0
C = 1
ELSE
C = 0
IP = IP+1 Subtract NEXT from TOS.
Drop NEXT.
SUB NEXT,TOS
TOS = [DSP--] - TOS
IF result < 0
C = 1
ELSE
C = 0
IP = IP+1 Subtract TOS from NEXT.
Drop NEXT.
XCH SWAP (TOS , [DSP])
IP = IP+1 Interchange values of TOS and
NEXT.
204 Neuron Assembly Instructions Listed by Mnemonic