Hlk Rm04 Wifi

The HLK-RM04 is a mature, low-cost embedded UART-ETH-WIFI module based on the Ralink RT5350F chipset. While it remains a popular choice for simple IoT projects and serial-to-WiFi conversions, it is increasingly being replaced by more powerful successors like the MT7688K series.

Technical Insights

• Dual Functionality: Supports AP, Client, and Router modes, allowing for versatile network setups including wireless bridging and acting as a standalone hotspot LaskakitOpenwrt.
• Protocol Stack: Built-in TCP/IP protocol stack enables direct transparent transmission between serial ports and Ethernet/WiFi ScribdRajguruelectronics.
• Practical Limitations: Actual data throughput is constrained by the UART interface, typically reaching only 5–7 KB/s in real-world serial-to-WiFi applications Rayshobby.
• End-of-Life Concerns: Due to limited memory (max 8MB Flash / 32MB RAM), OpenWrt official support for this module ended with version 19.07.10; it is currently not recommended for new Linux-heavy projects Openwrt.

Market & Pricing Trends

• Wholesale Pricing: Bulk prices on B2B platforms like Alibaba range from $0.80 to $2.40 per unit for bare modules, while development kits with adapter boards typically cost between $5.00 and $18.00 AlibabaAlibabaAlibabaAlibaba.
• Competitive Landscape: The broader WiFi module market is shifting toward WiFi 6/7 and higher-performance SoCs (like MT7688 or ESP32). The market for standard modules is projected to reach $81.29 billion by 2026, growing at a 13% CAGR Researchandmarkets.
• Successor Adoption: Newer modules based on the MT7688K (580 MHz) offer nearly double the clock speed and significantly more RAM support (up to 128MB), making them the preferred choice for industrial and high-performance IoT applications Laskakit.

The following file contains a curated list of HLK-RM04 modules, development kits, and compatible successors currently available on the market.