First look at JQ6500 modules

For some time, on different chinese webstores (for example Banggood) there is a module called JQ6500 for sale:

jq6500-001 jq6500-002

it’s often described as a voice sound module or as an MP3 player sound module.

Actually JQ6500 is the name of the main chip hosted on the module:


The chip is manufactured by a Chinese company named JQ. A datasheet for the chip is also available, unfortunately only in Chinese (but Google Translate can help to understand what it contains).

On the other side of the PCB, the module houses two additional integrated circuits:

  • a 16Mbit flash memory (25L1606E)
  • a 3W audio amplifier (HXJ 8002)

When you connect the module to your computer via USB, it is detected as a CDROM drive. If you browse the content of the CD, you can find the MusicDownload.exe application that allows to upload audio files in the flash memory:


The software is in Chinese but its use is very simple: by moving to the second tab you can select the MP3 files to be uploaded. If you now move back to the initial tab, you can start the upload process clicking on the only available button. In the video at the end of this post you can see how it works…

You can control the JQ6500 chip in different ways. The easiest one is using external buttons connected to pins K1-2-3-4-5:


When you press a button, the chip plays the corresponding audio file. For example if you press the button connected to pin K1, the chip plays the audio file named 001.mp3.

The onboard amplifier (HXJ 8002) is a mono IC and its output is connected to pin SPK+ and SPK-. You can therefore connect to those pins a small speaker. If you want a stereo audio, you can instead use pins ADL_L (left channel) and ADC_R (right channel) and connect them to an external amplifier.


This module is an excellent and inexpensive solution to add audio to your projects. The use of an internal flash memory has the advantage of not requiring SD cards or other media to store your audio files; in contrast its capacity (16Mbit = 2MByte) makes it more suitable to reproduce sound effects / guide voices than to make a music player.

In the next articles I will show you how to interface the module with Arduino … meanwhile here is a video showing my first tests:




Sansa MP3 Player Runs Doom Unplayably

DOOM, is there anything it won’t run on? Yes. Your front lawn cannot currently play DOOM. Pretty much everything else can though. It’s a testament to the game’s impact on society that it gets ported to virtually every platform with buttons and a graphical screen.

This video shows a Sansa Clip playing DOOM, but it’s only just barely recognizable. The Sansa Clip has a single color screen, with yellow pixels at the top and grey for the rest of the screen. The monochrome display makes things hard to see, so a dithering technique is used to try and make things more visible. Unfortunately it’s not particularly effective, and it’s difficult to make out little more than the gun at the bottom of the screen.

The stunt is achieved through the use of RockBox, a custom firmware for a wide variety of media players, from Apple to Toshiba. Through no small amount of effort, developers would reverse engineer different media players, often by disassembly of both hardware and firmware. Generally, the first steps involve determining the make and model of the controller, along with identifying how to access its programming pins & how to bypass any firmware protection that might be in place. Armed with this knowledge, they could then set about porting the RockBox code. The amount of effort poured into the project is staggering, as evidenced by this documentation for just one Rockbox port.

Rockbox also supports plugins to add functionality. One of these is Rockdoom, which acts as a basic DOOM engine that can load WAD files and play the game. Thus, if you’re keen to duplicate the hack, start out by porting Rockbox to your media player, and then download the Rockdoom plugin.

For another great example of custom firmware running on an obscure platform, check out [Sprite-TM]’s talk on hacking hard drive controller chips.

[Thanks to Itay for the tip!]

Filed under: portable audio hacks

Code Like an Egyptian

[Marcelo Maximiano’s] son had a school project. He and a team of students built “The Pyramid’s Secret“–an electronic board game using the Arduino Nano. [Marcelo] helped with the electronics, but the result is impressive and a great example of packaging an Arduino project. You can see a video of the game, below.

In addition to the processor, the game uses a WT5001M02 MP3 player (along with an audio amplifier) to produce music and voices. There’s also a rotary encoder, an LCD, a EEPROM (to hold the quiz questions and answers), and an LED driver. There’s also a bunch of LEDs, switches, and a wire maze that requires the player to navigate without bumping into the wire (think 2D Operation).

In addition to the code and hardware diagrams, there is a PDF file on GitHub describing more about the game. It is in Portuguese, though, so most of us will probably need a little translation help. However, a Brazillian site did have an English post about the game, which might be a good place to start.

You might not want to replicate the game, but it is a great example of how much an Arduino can do with some simple externals devices and some attention to packaging.

Sadly, most of our projects look more like this game (no offense to that hacker). Projects like this are way more likely to spark young people’s interest than a blinking LED or a capacitor meter. If you are more in the mood for arcade play, you can also check out Arduinocade.

Filed under: Arduino Hacks