Programming language 
I 
The 
AIS 
can be programmed in either a relay symbol language( a.k.a.  ladder logic 
or ladder mode) or  a logic symbolic language(a.k.a.  instruction list or list mode). 
The relay symbol language is based on  relay symbol representations and  allows 
any ladder to be programmed a form which is very similar to relay control sequence 
ladder. 
The  logic  symbolic  language  is  based  on  the  assembly  language,  one 
of 
the 
languages used to write microcomputer programs, and represents any program in 
the instruction, source, and destination parts. 
Any program written in either language is stored into the memory of the 
PLC 
after it 
has 
been  converted  into  the  machine  language.  This  conversion  process  is 
performed by the programming device used for programming the 
PLC. 
Relay 
Symbolic 
Language 
0 
LDX3 
1 ORX4 
2 
OR  X5 
3 
OUT 
Y33 
4 LD X5 
SANDMI1 
6 OR1  X6 
7 
OUT 
Y34 
8 
END 
Logic 
Symbolic 
Language 
73