IBM 8265, Site Preparation Manual, Page: 35 / 164

Chapter 3. Cabling Recommendations
19
Standards Used With Modular Wiring Connectors
50-Position to Modular Wiring
The 50-position to modular pin wiring in such components as the Harmonica,
Octopus, and Mod Patch Panel is called the sequence. There are seven standard
sequences: USOC, MMJ, 258A, 356A, 10BASE-T, EIA and OPEN DECconnect.
USOC:
This is the original US voice communications industry standard. Most voice
equipment is compatible with this sequence. Available in WE4W, WE6W, WE8W,
and WE8K modular polarization of four, six and eight wire channels.
MMJ:
This is an adaptation of USOC especially suited to asynchronous EIA-232 and EIA-
423 interface data equipment. Available in MMJ polarization, four and six wire
channels.
Figure 2. WE4W, WE6W, WE8W and WE8K Modular Polarization
Figure 3. MMJ Polarization
1 2 3 4 5 6 7 8
R4 R1 R2 R3 T4 T3 T2 T1
1 2 3 4 5 6 1 2 3 4
T3 T2 T1 R2 R3 T2 R1 R1 T1 R2
1 2 3 4 5 6
T3 R3 T1 R1 R2 T2