I would like to show you my new project. Shortly speaking it will be portable, battery powered C64 personal computer. I am a big fan of the C64 device. My codding begun on this device. I have one C64G device which I will modify a lot :) and post here a description of my work progress.
So what we have now?
Mini LCD screen
I connected cheap lcd car display used for back camera. This device have AV input so it was really easy to connect it. I removed all not necessary stuff and left lcd panel and electronics board which is mounted inside the C64. The lcd is powered from C64 board from 9V DC source used mostly for SID. If I have some time I will post photo where you can find this on board. Ok, so here you can find photo of the power source.
I mounted sd2iec on prototype board to check if it is working correct before I will make this device on PCB. I mounted this version. here. I used LarsP version of firmware which is correct for this layout. First you need to burn bootloader (newboot* file). I used this avrdude command to burn it : "avrdude -c usbasp -p m644p -U flash:w:newboot-m644p-larsp.hex:i -U hfuse:w:0x92:m -U efuse:w:0xFD:m -U lfuse:w:0xEf:m". After doing it put latest *.bin file to the root directory of the sd card and after turning on the device it will update the firmware. Board is working correct so I am planning to build one layer PCB for it. Ok so here is a current PCD work progres :) After first run I found small error in PCB. Boards below are OK. Please make sure that you solder Q1 correct because I mess up pin layout. http://www.eltop.republika.pl/sd2iec.html (PL) http://www.pitsch.de/stuff/mmc2iec/index.htm (EN) http://www.c64-wiki.com/index.php/SD2IEC (EN)
3. Stereo SID
I have found some time at weekend and mounted Stereo SID module. Available addresses for second SID are: d400, d420, d500, de00, df00. I was thinking how to mount preamp for second SID and came out to the idea of cutting whole preamp from another c64 board. So I did it. You need to connect point A and B between two boards. C connected to pin 1,2,3,4 are 22nF (new SID) or 470pF (old SID). C in audio line is 100nF. Address for second SID is selected by 74LS139. I put another SID on existing one and solder it together according to schema below.