5A DC-DC buck converter with volt and current meters

These nice little converters have both voltage and current meters and voltage and current limiting, and are designed as general buck converters or as battery chargers. The 3 pin header is also a serial interface but we haven't tested it to see what it's useful for (pinout is Gnd, RXD, TXD looking from edge of PCB).

Specs are:

Input voltage: 5V-32V
Output voltage: 1.27V-30V
Output current: adjustable maximum 5A
Conversion efficiency: up to 95%
Switching frequency: 300kHz
Output ripple: 50mV (max)
Load Regulation: ±0.5%
Voltage Regulation: ±2.5%
Operating Temperature: -40°to +85°C
Size: 51L x 26.3W x 14H mm

Voltmeter/Ammeter
Measurement accuracy: 0.1%
Refresh rate: about 200ms
Display: 0.28" red LED
Current range: 0-5A
Voltage range: 5V-30V

Comms details
This module allows a computer to read the current and voltage data of the module. Because this module outputs at TTL levels, you need a serial to TTL converter, such as a CP2102 usb to TTL converter to interface to the module.
The communication details, as supplied by a customer (thanks Colin M!), are below. Note that this was translated from the original Chinese and we have not verified any of this, but it should get you started:
Baud rate: 9600 bps
Commands are:
BB CC ADDR 00 XX XX CRC (current return command)
BB CC ADDR 01 XX XX CRC (voltage return command)
where
BB CC is a frame (two quarters)
ADDR is a module address (1 byte)
00 is the read current command (1 byte)
01 Read the voltage command (1 byte)
XX XX Arbitrary Value (2 bytes)
CRC CRC Check (1 byte)