The HW-044 is a popular, low-cost RS232 to TTL converter module based on the MAX3232 transceiver IC . It is primarily used to bridge the communication gap between devices that use RS232 serial standards (like older PCs, industrial equipment, or GPS modules) and microcontrollers that use TTL logic levels (like Arduino , ESP32 , and Raspberry Pi ). Core Technical Specifications The HW-044's performance is defined by its onboard MAX3232 chip , which is an upgraded version of the classic MAX232 that supports lower voltage ranges.
The HW-044 is a MAX3232-based converter module designed to interface RS232 signals with TTL levels (3.3V-5V) for microcontroller communication. It is commonly applied in serial communication tasks, including firmware flashing and device upgrades. For technical specifications, see the documentation at Amazon .
Informative Text: HW-044 LED Display Module (MAX7219) 1. Overview The HW-044 is a compact, pre-assembled module designed to drive common-cathode LED displays. Its core component is the MAX7219 integrated circuit from Maxim Integrated (now Analog Devices). The module allows microcontrollers (e.g., Arduino, ESP32, STM32) to control up to 64 individual LEDs (8 digits of 7-segments plus decimal points, or an 8x8 dot matrix) using only three I/O pins . 2. Key Features
Driver IC: MAX7219CNG (or similar variant). Supply Voltage: 5V DC (logic and LED power). Logic Level: 5V tolerant; 3.3V logic may work but is not guaranteed for all units. Current Control: Digitally adjustable segment current via a single external resistor (usually pre-soldered as an RSet resistor). Communication Protocol: Serial, 16-bit data packets (DIN, CLK, LOAD/CS). Display Type: Supports common-cathode 7-segment displays or 8x8 LED matrices. hw-044 datasheet
3. Pinout Description (5-pin interface) | Pin Name | Function | |----------|--------------------------------------------| | VCC | 5V power supply input. | | GND | Ground. | | DIN | Serial Data Input (MOSI from master). | | CS | Chip Select / LOAD (latches data into registers). | | CLK | Serial Clock (up to 10 MHz typical). | Note: Some variants label CS as LOAD or CS. 4. Maximum Ratings (Absolute)
Supply voltage (VCC – GND): 0V to +6V. Input voltage (any pin): -0.3V to VCC + 0.3V. Continuous LED segment current: 40 mA (max). Operating temperature: 0°C to +70°C (commercial grade).
5. Communication Protocol The HW-044 uses a 3-wire SPI-like interface: The HW-044 is a popular, low-cost RS232 to
Data format: 16-bit words (D15–D0).
D15–D12: Not used (don't care normally). D11–D8: Register address (4 bits). D7–D0: Data bytes.
Procedure:
Pull CS low. Send 16 bits, MSB first, on DIN at each rising edge of CLK. Pull CS high to latch the data.
Example registers: