CPU Function, depending on CPU and STEP 7 Version4-2 PLC S7-300, CPU Specifications CPU 312 IFM to CPU 318-2 DPA5E00111190-014.1 Differences between CPU 3182 and CPUs 312 IFM to 3162 DP4 rechargeable batteries for 318-2CPU 318-2 CPUs 312IFM to 316-2DP4 accumulators 2 accumulatorsThe following table shows you what to watch for if you want to use an STL userprogram of a CPU 312IFM to a CPU 316-2DP for the CPU 318-2.Instructions User Program from the CPU 312IFM to 316-2DP for theCPU 318Double integer math(+I, –I, *I, /I;+D, –D, *D, /D,MOD;+R, –R, *R, /R)The CPU 318 transfers the contents of accumulators 3 and 4to accumulators 2 and 3 after these operations.If accumulator 2 is evaluated in the (accepted) user program,you now receive incorrect values with the CPU 318-2because the value has been overwritten by the contents ofaccumulator 3.ConfigurationFrom 312 IFM to 316-2 DP CPUs, the CPU 318-2 “imports” only projects createdwith STEP 7 V 5.x.You cannot operate programs containing FM or CP (SDB 1xxx) configuration data(e.g. FM 353/354) in a CPU 318-2!In this case, the respective project needs to be edited accordingly or recreated.Starting a Timer in the User ProgramThe accumulator register in CPU 318–2 must contain a number in BCD formatwhen starting a timer in your user program (e.g. with SI T).ForceThe differences of force operations are described in Chapter 1.3.1.Loading the User Program to the Memory CardCPU 318-2 CPUs 312IFM to 316-2DP... using the PD function Load UserProgram... using the PD function Copy RAM ToROM or Load User Program
