Hacking an AVR programmer Green. Photonssee also my recent appendix to this topic Hacking an AVR programmer II especially if you have an ATmega. On e. Bay I recently purchased a set of cute small USB AVR programmers which I intend to use in the course 1. TE6. 63 Microcontroller Programming at Uppsala University. MK USBISP V3. 0. Bay. After waiting for one month for the delivery from China the package finally arrived today. Unlike other programmers which I purchased before, these come with a sturdy aluminum shell and in happy colors. However, connecting the first programmer to my PC brought me quickly back to earth it was not recognized as an USBasp. OK, it would not be the first delivery from China with broken or counterfeit electronics, so I tested the second oneAt that time I got a bit confused, because the programmer registered as an HID unit on the USB with vid0x. Serial Boot Loader Avr' title='Serial Boot Loader Avr' />EB pid0xc. Not as an USBasp with vid0x. In computing, booting or booting up is the initialization of a computerized system. The system can be a computer or a computer appliance. The booting process can be. WiseFixer is a professional and advanced system optimizer tool to help users easily and conveniently fix system errors,clean registry,optimize system to speed up PC. Introduction How to Change Fuse Bits of AVR Atmega328p 8bit Microcontroller Using Arduino. This is the point where I usually ask Google. So I did and I found some threads discussing the same issue and pointing out, that these programmers needed a different software and were not at all compatible with avrdude. Serial Boot Loader Avra' title='Serial Boot Loader Avra' />BAD But of course, one should be able to reprogram the programmer using another programmer. At my home this is not a henn and egg problem, since I have accumulated several AVR programmers. Ok, I downloaded the USBasp firmware from Thomas Fischl, flashed the programmer after inserting the self programming jumper Self programming jumper on the MK USBISP V3. AVR programmer. Since the original firmware is protected by the lock bit fuses, I had to fully erase the chip first, then set the fuses correctly to HFUSE0xc. LFUSE0xef and then flash the. I tried first the 2. Thomas Fischl and the first observation was that instead of the red LED which was on previously, now the programmer showed a blue light. Serial Boot Loader AvroBut Windows would not at all recognize this device as any USB device. Nothing showed up. I got confused. I tried both Win. XP and Win. 7 to no avail. Well, perhaps this programmer was not hardware compatible to the USBasp Lets have a lookAVR programmer MK USBISP V3. AVR programmer MK USBISP V3. There are some tiny, yet important, differences to the original USBasp programmer in the USBasp USB D is connected to pin PB0, USB D to PB1 and PD2INT0. Here also USB D was connected to a pin on port D PD3INT1. Well, this should not really make a difference, and I continued my search for differences. OK, for some reason, also the LEDs are connected in parallel to 2 port pins each so whatIn despair I decided to look into the source code of the USBasp firmware. The header files OK pin assignments were as expected, nothing special here. Free Turbo Grafx 16 Emulator For Ds. But lets wait, where is the definition of the utilization of port D Well, it was in the main. USB and ISP pins PORTD 0 PORTB 0 all outputs except PD2 INT0 DDRD 1 lt lt 2 hey wait a second All pins of port D are defined as output, except for PD2INT0 I always tell my students to only define pins as output, which are really used as output And what happens hereSince the modified design also connected USB D to PD3INT1, the rather aggressive definition of output pins leads to a unsolvable conflict, when suddenly PD2 is driving against the USB signals from the host Changing this little piece of code solved the problem. Rather conservative I set all pins of port D as input none of them is currently used as output int mainvoid. USB and ISP pins PORTD 0 PORTB 0 all PDx input MK USBISP v. DDRD 0x. 00 I compiled the code, flashed it onto the AVR programmer using another AVR programmerand behold it works I will contact Thomas Fischl and tell him about this observation perhaps the modification will be implemented in the distributed firmware on his homepage. Here is a. zip archive of the modified firmware. The. hex file for use with an ATmega. Download ZIP archive 2.