Bradley Smoker PLC-5 Specifying Indirect Addresses, Word Level Example Bit Level, Ton, Tof, Rto

4-18Addressing I/O and Controller Memory

To Specify the Address of a Use these Parameters

Bit within a binary file

B 3 / 2 4 5

Bit Delimiter

Bit Number

Binary files are bit stream continuous files, and therefore you can address them in two ways: by word and bit, or by bit alone.

Bit within a structure file

R 6 : 7 . D N

File Type

File Number

File Delimiter

Structure Number

Member Delimiter

Member Mnemonic

You can also use mnemonics to address members at the word or bit level. The available mnemonics depend on the type of data (timer, counter, or control) and the program instruction. For example:

Instruction Type	Word Level	Example	Bit Level	Example
Timer	preset .PRE	T4:1.PRE	enable.EN	T4:0.EN
TON, TOF, RTO	accumulated.ACC		timing.TT
			done.DN

For information about the mnemonics for a specific instruction, see chapter 22 of the PLC-5 Programming Controller Instruction Set Reference, publication 1785-6.1.

Specifying Indirect Addresses

ATTENTION

When using indirect addressing, make sure that the indirect address points to a valid data file or element. During Run mode, if ladder execution encounters an invalid or out-of-range indirect address, a run-time error occurs and the controller halts.

The controller uses the value from the pointer address to form the indirect address. You can use ladder logic to change the value stored at that substitute address.

Publication 1785-UM012D-EN-P - July 2005