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WiFi232 – An Internet Hayes Modem for your Retro Computer
RS232 Serial Wifi Modem for Vintage Computers V4 from The Old Net on Tindie
Serial wireless Wi-Fi Adapter with RS232, RS485 and RS422 interfaces
GitHub - mecparts/RetroWiFiModem: An ESP8266 based RS232 <-> WiFi modem with Hayes AT style commands and LED indicators