Page: 4Service Guide ML390/391Chapter 1 Product Specifications1.1.02 Compatibility - Microline 390/391 vs. Microline 390/391-PlusThe differences between the Microline 390/391 and Microline 390/391-Plus printers are listed below.Hardware Differences· Operator Panel· Operator Board· Character Generator Programmable Read Only Memory (CGROM)· Programmable Read Only Memory (PROM)· Middle CoverOperational Differences· "Plus" printers have more resident fonts.· In the "Plus" printers, data in the receive buffer is printed upon receipt, without having to wait for a lineterminator character (CR/LF or FF).· In the "Plus" printers, the DC1/DC3 Acknowledge/Ignore, Receive Buffer Size, and RESET inhibit can becontrolled through the printers Menu.Serial Number Revision LevelsMicroline 390/391ARev A units are original production units. An interconnect module connects the power supply board to themain control board.BRev B units are retrofitted to include a modified interconnect module, which prevents corrosion.CThese units have a cable connection between the power supply board and the main control board. Thecable connection wire replaces the interconnect module.Microline 390/391-PlusRevision levels do NOT apply to the "Plus" printers.NOTE:Please refer to the parts lists for parts differentiation. Please be sure of the parts you need before orderingto avoid confusion and incorrect parts orders.Printer Serial Number IdentificationThere are three serial number revision levels for the printers. Hardware differences exist between levels.To identify the revision level of a printer, record the serial number from the back of the printer. Refer to thefollowing to decode the serial number.
