This would be a lot easier with a display kit purchased from PJRC, which comes with the correct firmware installed on the display, a working pushbutton board, and the two cables needed. The PJRC display comes with a 4-pin plug that mates with the MP3 player, but it is easy to use with a PC instead of the MP3 player, as described above. But with a
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raw display, the firmware chip that comes installed is useless and you must replace it with one that has the LCD. HEX firmware (that PJRC provides as a free download including source code, even though you purchased the LCD elsewhere!) You will need to program a flash rom or EPROM with LCD. HEX and replace the socketed chip that came with the board. You will need an EPROM programmer, and the correct DIP-PLCC socket adaptor to hold the chip while it is in the programmer (beware, the common 32-to-28 pin adaptor will not work, you need 32-to-32). The socket is wired for a 32 pin flash rom pinout, not the 28-pin 27Cxxx eproms that have 4 unconnected pins when purchased in 32 pin PLCC. I use the 39SF512 chip in the displays from PJRC. Update: now you can buy a pre-programmed firmware chip. PJRC provides these chips to allow you to make use of your JW-002 LCD (purchased from a third party), but PJRC does not provide the pushbutton board and custom ribbon cable separately for use with LCD purchased elsewhere. This step is absolutely required. If you don`t have an EPROM programmer, you must borrow or buy one, or find someone who has one to program the chips for you. No matter how badly you want those displays to work, you`re not going to get far with the original chip that comes installed with AT&T`s old firmware. The display does not care if you have access to an EPROM programmer or not. If you can`t get a chip with LCD. HEX...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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