IBM 4400 manual Epson Emulation Exceptions and Differences

Chapter 6 Introduction

Epson Emulation Exceptions and Differences

Because of mechanical differences between your printer and Epson printers (moving printhead serial matrix printers), some Epson features are approximated or not supported.

•Epson codes that produce different behavior in your printer are indicated by a “dagger”†() in the Control Code Index and code section.

•Epson bit-image graphics are supported, including all plotter and CRT densities.

•Many character sets are available, including IBM-PC Graphics (IBM Code Page 0437) and Epson. You can configure the zero character to contain a slash or no slash.

•Like the Epson FX-1050, the Double Wide print control codes (ESC W, SO) double the character width. Unlike the Epson FX-1050, however, these codes do not double the inter-character spacing. The formulas for total character spacing are as follows:

Epson FX-1050	2 (char + 1 dot + space)
Epson Emulation	2 (char + 1 dot) + space

•The Condensed Print (SI) control code condenses the character width but not the inter-character spacing, unlike the Epson FX-1050, which condenses both character width and spacing.

•If one or more Backspace control codes follow directly after a Bit Image Graphics command (ESC K, ESC L, ESC Y, or ESC Z), the printer backspaces into the graphic pattern, the number of dots depending on the current cpi setting. For an Epson FX-1050 printer, one Backspace sends the logical printhead directly to the beginning of the graphics pattern.

•When backspacing over proportionally spaced characters, Epson printers move back the width of each proportional character; this emulation moves back based on the current cpi setting, as if proportional spacing is disabled.

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