A dial-up modem in your pocket: the D-Modem app for Android and iOS.
The app is a V.92/V.90/V.91, V.34 and class 1 fax modem whose telephone line is a SIP account's G.711 call, over Wi-Fi or mobile data. The modem is D-Modem's open modem core and DSP, built for the phone; no modem hardware is needed. Toward a BBS on a real phone line it is the digital modem, up to 56000 bit/s downstream; toward another digital modem, V.91 at up to 62667 bit/s both ways.
- A terminal, a dialling directory and the modem's AT console
- Class 1 fax up to 14400 bit/s: PDFs and images sent, faxes received as PDFs, T.38 too
- A vintage computer's external modem, on a USB serial adapter, pico-serial, Bluetooth serial or TCP
- Real phone lines through USB modems (the pico-serial Line stick among them), a Hayes modem on a serial adapter, or a Bluetooth modem
- Two phones as each other's line over Wi-Fi or Bluetooth, no SIP account needed
- The phone's own mobile calls as a slow line, where Android allows it
Android: open the project in Android Studio, or
git submodule update --init
./gradlew assembleDebug
iOS: see docs/ios.md. The full steps, Docker included, are in docs/building.md.
The documentation is also a website, d-modem.github.io/app, with reference pages made from the code.
docs/ covers the modem's lines, fax, adapters and phone lines, every screen of the app, building for Android and iOS, and the source layout.
| Repository | What it is |
|---|---|
| D-Modem | The open V.92 softmodem: dmodemd, libdmodem and the Asterisk, FreeSWITCH and ARI modules |
| app | The D-Modem app for Android and iOS: a dial-up modem on a SIP call |
| hardware | pico-serial: RP2040 serial adapters and phone-line USB sticks |
| menu | modemmenu: the login and menu dial-up callers reach |
| bbs | A bulletin board for telnet, SSH, TN3270 and modem callers |
| go3270 | A Go library for 3270 terminal servers, used by bbs |
| brand | Logos, colours, type and the naming guide |
GNU Affero General Public License version 3 only (COPYING), or a commercial licence from the D-Modem Authors (COMMERCIAL-LICENSE.md), as D-Modem (see its LICENSING.md for the parts it fetches: libre is BSD-3-Clause, Mbed TLS Apache-2.0). Contributions come with a contributor agreement (CONTRIBUTING.md).