Emulation exceptions

Instruction exceptions

There are several instructions that RSLogix Emulate will not emulate . These are listed in the table below:

Mnemonic	Instruction	Execution
BTR	Block Transfer Read	There is no real I/O to read. The software will not emulate the actual transfer of data, but the enable (.EN) and done (.DN) bits are emulated. When a BTR is "executed," the enable bit is set during the first scan, then the done bit is set during the second scan. If you wish, you may use debug files to emulate the data transfer.
BTW	Block Transfer Write	There is no real I/O to read. The software will not emulate the actual transfer of data, but the enable (.EN) and done (.DN) bits are emulated. When a BTW is "executed," the enable bit is set during the first scan, then the done bit is set during the second scan. If you wish, you may use debug files to emulate the data transfer.
COR	Custom Output Routine	The COR instruction passes parameters to a Custom Application Routine (CAR) file. CAR files are not emulated in any way. The instruction is not executed.
CPW	Copy Word	(SLC 500 only) This instruction is not executed.
DLG	Data Log	(MicroLogix 1500 only) The data logging function is not emulated. The instruction is not executed.
GCD	Gray Code	(SLC 500 only) This instruction is not executed.
HSC	High Speed Counter	(SLC 500 only) This instruction is not executed.
IDI	Immediate Data Input	There is no I/O image table to update in the software. This instruction is not executed.
IDO	Immediate Data Output	There is no I/O image table to update in the software. This instruction is not executed.
IID	I/O Interrupt Disable	(SLC 500 only) There is no I/O to generate an interrupt, therefore this instruction has no effect.
IIE	I/O Interrupt Enable	(SLC 500 only) There is no I/O to generate an interrupt, therefore this instruction has no effect.
IIM	Immediate Input with Mask	(SLC 500 only) There is no I/O to update, therefore this instruction has no effect.
IIN	Immediate Input	There is no I/O image table to update in the software. The instruction is not executed.
INT	Specialty I/O Interrupt	(SLC 500 only) There is no I/O to trigger an interrupt, therefore this instruction has no effect.
IOM	Immediate Output with Mask	(SLC 500 only) There is no I/O to update, therefore this instruction has no effect.
IOT	Immediate Output	There is no I/O image table to update in the software. The instruction is not executed.
MSG	Message	Even though the software provides Data Highway Plus emulation and Channel 0 emulation, the MSG instruction emulates only the enable (.EN) and disable (.DN) bits. When the emulator scans a MSG instruction, the EN bit is set during the first scan, and the DN bit is set during the second scan. If you wish, you may use debug files to emulate the data transfer.
PID	Proportional, Integral, Derivative	The software does not attempt to execute the PID instruction or change any of the PID control bits or words.
PTO	Pulse Train Output	(MicroLogix 1200 and 1500 only) There are no outputs. The instruction is not executed.
PWM	Pulse Width Modulation	(MicroLogix 1200 and 1500 only) There are no outputs. The instruction is not executed.
RCP	Recipe	(MicroLogix 1500 Series C only) This instruction is not executed.
REF	I/O Refresh	(SLC 500 only) There is no I/O to refresh, therefore this instruction has no effect.
RPI	Reset Pending I/O Interrupt	(SLC 500 only) This instruction is not executed.
RPI	Reset Pending I/O Interrupt	(SLC 500 only) There is no I/O to generate an interrupt, therefore this instruction has no effect.
RTA	Real Time Clock Adjust	(MicroLogix 1200 and 1500 Series C) This instruction is not executed.
SVC	Service Communications	(SLC 500, MicroLogix 1200 and 1500) There are no processor communications to service, therefore this instruction has no effect.

Processor feature exceptions

Processor Feature	Execution
Checksum tests	The emulator cannot perform a processor checksum. If you attempt to access the emulator from a computer other than the one running the emulator, RSLogix 5 will attempt to get the emulator to perform a checksum calculation. This calculation will fail, and RSLogix 5 will appear to hang. You can cancel the calculation and continue.
Partial downloads	The emulator does not support partial downloads.
Custom Application Routines (CARs)	CARs are not ladder logic and are not executed in any way.
Floating Point and other Math Functions	Floating point and other math instructions are emulated by the software. However, since the software and the processors use different microprocessors (PLC-5 and SLC 500 processors use Motorola CPUs and the software uses your computer's CPU), the results of the calculations may differ, particularly in floating point math and in integer math involving rounding.
I/O Status	None of the I/O status information is used by the software.
Multiple Main Control Programs (MCPs)	You can execute one program file at a time. Subroutines called by the single program will be executed.
Processor Configuration	The software does not use all of the information stored in the processor configuration. The STI configuration, fault file configuration, and watchdog timer are all used by the software. In the case of the watchdog timer, you can set the timeout value to zero to disable the watchdog timer while emulating. Note that the processor will fault immediately upon being switched into Run mode if the watchdog timer is set to zero. You can use the fault options dialog to set how the software handles the watchdog timer.
Processor Input Interrupt (PII)	The software makes no attempt to emulate the PII. There are no real inputs to generate the interrupt.
Processor Status	Active Node Status, EEPROM status, etc. are not emulated. Processor status bits and fault codes are emulated. Processor scan time and maximum scan time are updated. The first-scan bit is emulated, but only on a Program to Run mode transition.
Sequential Function Charts	You can emulate individual step and transition files, but the SFC cannot be emulated.
User Interrupt File	You may emulate the user interrupt file, but there is no means to trigger its execution. You could emulate it by making it the main file, or by programming a JSR instruction to go to the interrupt file.