Code 39

Kind	Charset	Capacity	URL	Phone
1D linear	A-Z 0-9 subset	Unbounded*	No	Yes

Uppercase-only linear barcode, one of the oldest and simplest symbologies still in common use (inventory labels, ID badges). Self-checking by design; an optional Mod 43 checksum adds a second layer.

Example

Code39::create('CODE 39')->withChecksum(true)->render();

Usage

use Atelier\Barcode\Code39;

echo Code39::create('BIN-0042')
    ->scale(2)
    ->height(70)
    ->wideRatio(3)
    ->withChecksum(true)
    ->render();

Options

Method	Default	Description
`scale(int)`	`2`	pixels per module
`height(int)`	`80`	bar height in pixels
`margin(int)`	`10`	quiet zone, in modules
`wideRatio(int)`	`3`	wide-to-narrow bar ratio, minimum `2`
`foreground(string)`	`#000000`	bar color
`background(string)`	`#ffffff`	background color
`withText(bool)`	`true`	show the human-readable value under the bars
`withChecksum(bool)`	`false`	append a Mod 43 check character

modules() returns the raw bar pattern instead of SVG.

The same value at wideRatio(2) instead of the default 3. Narrower wide bars make a shorter symbol, at the cost of the margin a scanner has to tell the two widths apart.

Limits

Charset is digits, uppercase A-Z, space, and - . $ / + % only; anything else throws InvalidCodeException. No lowercase, no punctuation beyond that set.
The * start/stop character cannot appear in the data itself: it throws if present.
No maximum length enforced by this library.

Unbounded = no hard cap in this implementation; physical/print width is the real constraint.