A weblog focused on interesting circuits, ideas, schematics and other information about microelectronics and microcontrollers.
JTAG and SPI AVR8 interface.
This construction is based on HappyJTAG Idea, to implement JTAG interface into target avr system and debug it remotly via USB, without specific JTAGICE hardware. This version uses specialized FT2232 chip, which has integrated JTAG interface on chip. It radically reduces USB interface communication and speed up overall process. There are two channels in FT2232, Channel A is used for JTAG and channel B is still free for standart serial communication between target and host PC.
Unfortunatly, the FT2232 chip requires more components than FT232 to work. For example, external crystal oscillator, few more resistors and so on. But the result is balanced, because of overall performance is 100 times better if you compere with original HappyJTAG version.