Allen-Bradley 1747-L543 SLC 5/04 Processor 64KB By wayne No Comments on Allen-Bradley 1747-L543 SLC 5/04 Processor 64KB 3 Min Read Buy the Allen-Bradley 1747-L543 SLC 5/04 processor with 64KB memory. It handles 4096 I/O and features DH+ and RS-232 ports for medium to large applications.