HP 5L (C3941A) manual Formatter System, Read Only Memory ROM, Random Access Memory RAM

Formatter System

The Formatter PCA is responsible for the following:

∙Receiving and processing print data from the printer interface.

∙Monitoring Front Panel Button and relaying printer status information.

∙Developing and coordinating data placement and timing with the print engine.

∙Storing font information.

∙Communicating with the host computer through the Bi-Directional Interface.

The Formatter PCA receives print data from the Bi-Tronics Interface and converts it into a dot image. The DC Controller synchronizes the Image Formation System with the Paper Feed System and signals the Formatter to send the print image data. The Formatter sends the print image data (dots) in the form of a VIDEO signal and the printing process begins.

The Formatter PCA also provides mounting locations for additional memory.

CPU

The Formatter PCA incorporates a Motorola 68030 custom-built microprocessor operating at 24 MHz.

Read Only Memory (ROM)

Besides storing microprocessor control programs, the ROM stores dot patterns of internal character sets (fonts).

Random Access Memory (RAM)

The RAM stores printing and downloaded font information received from the host system and temporarily stores a full page of print image data before the data is sent to the print engine. (See “Page Protect” later in this chapter.) Memory capacity can be increased by adding a DRAM memory card to the Formatter PCA. Note that adding memory may also increase print speed when printing complex graphics.

Parallel Interface

The Formatter PCA receives incoming data through its Bi-Tronics interface. The Bi-Tronics I/O provides high speed and two-way communication between the printer and the host, allowing the user to change printer settings and monitor printer status from the host computer.

5 - 8 Functional Overview