I have received XPlain kit so many days ago but i had no chance to evaluate it. Because so many days have passed since i got the kit, i had to stop my current works and made a review for the kit to share with you.
Physical View
First of all, the kit came in a small and well covered box. It is a small board but contains so much components on it such as Usb,Leds,Buttons,SD Ram, Flash, Speaker, Connectors for internal I/Os and programming. When you hold the board in your hands, it looks very nice and it is really well designed.
Board Components
ATxmega128A1 ( Main Microcontroller )
AT90USB1287 ( Usb-rs232 gateway and bootloader )
8 MB SD ram
8 MB Dataflash
8 Leds
8 Buttons
Speaker
JTAG connectors both for ATxmega128A1 and for AT90USB1287
Usb connector for Virtual COM port
Trimpot
Documentation
As others stated, there is no any documentation and any CD for the software; just the address located on the box itself. For this reason, i spent so much time to find and download the necessary documentation and software in the Atmel website.
Installation
The installation is easy. You don't have to do anything, just run the installation utility, that is all. What ? What is the name of the installation utility ? Ouch ! it is AVR Studio. Was it ? Or , did i do something wrong ?
Software
In this stage, the is not so much thing to test the kit. You have 8 leds and 8 buttons, one virtual com port via USB. So, when you press a button you hear a sound via speaker on the board. Just the voice heard when you press the button 4 is acceptable and the rest are quite bad. In the meantime, after powering the kit, the preloaded program in the ATMega chip runs and you see the leds are lit from up to down. In a dark place it looks very nice. I could not test the COM Port. In fact, i could not find a way to test com port. The Hardware Guide says,
"The XMEGA’s UARTC0 is connected to a software UART on the AT90USB1287. The AT90USB1287 UART is communicating at 9600 baud, using one start bit, eight data bits, one stop bit and no parity.
When the AT90USB1287 device is enumerated (connected to a PC) the data transmitted from the XMEGA is passed on to a (virtual) COM port. This means that it is possible to use a terminal program to receive the transmitted data on a PC.
Similarly data transmitted from the PC COM port is passed on to the XMEGA UART through the gateway. If the USB device is not enumerated, e.g. powering the kit from an USB supply adapter, the AT90USB1287 device’s UART will operate in loop back mode (echo back everything it receives)."
But neither i did receive any byte in the terminal program ( Absolute Telnet ) nor was able to send a data byte. Maybe i am missing a point.
AT90USB1287 has a bootloader in it and it is evoked by a simple jumper placing in the J200 connector which is , in the meantime, a JTAG header to re-program the AT90USB1287 chip. So, if you want to update or change the Usb-rs232 part of the chip you may start the bootloader and use FLIP module to upload new program. But if you want to change the bootloader firmware then you need an external programmer adapter to upload via JTAG header.
It is not supported to re-program the ATxmega128A1 chip via usb port. So, if you want to re-programm the XMega chip then you definetly need an external programmer adapter.
Hardware
I could not find the hardware schematics of the board. This would be very nice and help deeply understand the bord design. Acording to the Hardware Guide, the board may be powered by an external adapter but i could not see any power socket for this purpose. The board is able to mesure the power consumption but for this you need to remove the Zero-Ohm resistor R400 and replace it a suitable one.
POS's
Very small and nice board
Comes with preloaded firmwares
Has SD Ram
Has Dataflash
Has Usb connector for Virtual COM port
Powers from Usb port
Has many leds and buttons
Has a speaker
Has an audio amplifier
Has connectors for unused IOs
CON's
ATxmega128A1 can not be programmed via Usb port
Needs an external programmer adapter to programm the ATxmega128A1 and AT90USB1287 ( if it is needed )
No connector for powering the board externally ( Hardware Guide says that it is possible )
Speaker voice is not good ( maybe sampling rate is not enough in the preloaded code )
There is no hardware schematics ( at least, i could not find any )
There is no given firmware code so you should wirte and upload your own code
Comments
A programming adapter may be given with the kit. This is really a big Con's to me. There is no any protection thing under the board, some companies like Microchip place plastic feet under their board to prevent any short-circuit possibility and damage. It is really a cheap board, even you need to buy a programmer adapter to dive deep into the board. So, it is a buyable kit.
