MUNBYN ITPP047 printer library

C library, Node.js bindings, and browser ESC/POS command builders for the MUNBYN ITPP047 thermal receipt printer. The bundled programming manual, version 1.00 is the reference for documented commands and parameter limits.

Repository

• src/: C API and USB device, serial, and IPv4 TCP transports.
• packages/node/: native Node.js bindings, TypeScript declarations, and terminal.
• packages/web/: browser command builders, WebSerial, and WebUSB transports.
• examples/: C examples; several print immediately when run.
• tests/: protocol, timeout, and installed-package regression checks.
• docs/COMMAND_COVERAGE.md: manual reconciliation, extensions, and limitations.
• docs/IMPLEMENTATION_STATUS.md: completed fixes, migration examples, and remaining hardware checks.
• docs/ITPP047_COMMAND_MATRIX.csv: all 73 manual command families mapped to the three APIs.

Build and test the C library

Requires a C99 compiler, CMake 3.16+, and Python 3 for tests. Linux is the validated native platform. macOS uses the POSIX implementation but has not been validated on hardware. Windows native transports and Bluetooth are not implemented; opening them returns an error.

./build.sh --test
# A build directory outside the repository also works:
./build.sh --build-dir /tmp/munbyn-build --test
# Static library and checks:
./build.sh --static --no-examples --test

The traditional make all shared builds the library and examples. CMake also supports installation and find_package; see CMAKE.md.

#include "munbyn_printer.h"

int main(void) {
    munbyn_handle_t printer = NULL;
    if (munbyn_open_network("192.0.2.10", 9100, 2000, &printer) != MUNBYN_OK)
        return 1;
    munbyn_error_t result = munbyn_initialize(printer);
    if (result == MUNBYN_OK)
        result = munbyn_print_and_cut(printer, "Hello, world!\n", MUNBYN_CUT_PARTIAL);
    munbyn_close(printer);
    return result == MUNBYN_OK ? 0 : 1;
}

Replace the example address with the printer's IPv4 address. For USB use munbyn_open_usb("/dev/usb/lp0", &printer); for serial use munbyn_open_serial("/dev/ttyUSB0", 9600, &printer).

Node.js

Requires Node.js 18+, a C/C++ compiler, and Python for node-gyp.

npm --prefix packages/node ci
npm --prefix packages/node test
node packages/node/tools/printer-term.js <printer-ip>
# Read-only live check; add --print to produce one verification receipt:
node packages/node/tools/check-printer.js <printer-ip>

const { MunbynPrinter } = require('./packages/node');
const printer = new MunbynPrinter();
try {
  printer.openNetwork('192.0.2.10');
  console.log(printer.getStatus());
  printer.initialize().print('Hello, world!\n').feedLines(7).cutPaper();
} finally {
  printer.close();
}

The binding is synchronous; reads block the calling thread up to the transport read timeout. Use a worker thread when necessary. Rebuilding synchronizes the C sources into an ignored core/ directory. npm pack includes those sources, so the package can build independently of this repository.

Browser

npm --prefix packages/web ci
npm --prefix packages/web test

import { MunbynPrinter, WebSerialTransport } from './packages/web/dist/index.js';
const printer = new MunbynPrinter(new WebSerialTransport({ readTimeoutMs: 1000 }));
await printer.connect(); // Invoke from a user gesture to show the port chooser.
try {
  await printer.initialize();
  await printer.print('Hello, world!\n');
} finally {
  await printer.disconnect();
}

Serve the browser example from HTTPS or localhost. WebSerial/WebUSB availability and device permissions depend on the browser and OS. Browsers do not connect to raw printer TCP port 9100 through these transports; use the Node package for network printing.

The browser package uses bwip-js/browser for local PDF417 encoding. Use a bundler, or the import map in packages/web/examples/index.html when serving the built modules directly.

Command behavior

Status requires all four one-byte DLE EOT replies. Missing or malformed replies are errors, never healthy defaults. USB devices with no return channel may still print successfully while status reads fail. A browser read timeout closes the transport to prevent late responses from contaminating the next request. Reconnect after a timeout, and await operations sequentially on each printer.

Native QR/PDF417, GS1, proprietary self-test, and Wi-Fi configuration are firmware-dependent extensions absent from the bundled manual. Successful writes confirm transmission only; inspect printed output to establish firmware support. See command coverage before using these extensions.

The C raster API requires the caller to supply a buffer of ((width + 7) / 8) * height bytes. Node/browser wrappers check its length. Barcode string APIs reject embedded NUL in the bindings. For binary barcode payloads, use munbyn_print_barcode_bytes, Node Buffer, or browser Uint8Array. Payload alphabets, lengths, CODE128 sequences, and GS1 wire syntax are checked before sending. Applications remain responsible for GS1 application-identifier semantics and firmware support.

print() retains its raw UTF-8 behavior. For printer code pages, use printEncoded(text, encoding, selector) with an explicit encoding and the selector from your printer's code-page sheet. Conversion rejects unrepresentable characters before sending. Legacy enum names do not establish the mapping on your firmware. See text encoding.

Node/browser printPdf417() now encodes locally and prints a raster image. Their default itpp047-tested profile blocks native PDF417, which printed command text on the tested unit. printPdf417Native() is available with an explicit generic profile for other, independently verified firmware. The C native API retains its behavior; opt into MUNBYN_PROFILE_ITPP047_TESTED to block it there. The live receipt includes raster PDF417; --native-pdf417 adds the experimental native diagnostic. See implementation status for migration and verification limits.

License

MIT.