SID files player of own construction

This is a prototype device on two universal boards. All connections are made with cables. The main element of the system is Atmega32, which is a simple emulator of a processor from C64 6502. Original SID system was removed from C64. The program was written in Bascom.
In the first phase of designing, there was only one SIID file which was attached to the program using $inc. Later, a support for SD cards was added. The program reads SID files from: root or “first folders”.
Functions of the player:

• fast forward
• pause
• change folders front/rear
• change SIDs inside folders front/rear
• change SIDs inside SID files

The system is powered by 12V. Stabilizer 5V for Atmega32 general power, Stb. 3,3V for DS card and Stb. 9V for SID as a second power. Additional resonator 4MHz through 4011 and 4013 systems creates a TTL clock generator needed to revive the SID.



Video:

player SID.3gp - YouTube

While connecting the RAM to Atmega, it is worth to rely on this diagram:

https://sklep.avt.pl/photo/_pdf/AVT270.pdf

except that there the CS signal of the RAM is connected by an inverter to one pin. In this project, each CS is connected to a separate pin. The point is that the port connected to the RAM is shared with the SID.



Audio output, schema redrawn from the original C64.



The system generating the clock for SID. It is based on the schema:

PDF: https://www.edw.com.pl/pdf/k04/45_12.pdf


Link to original thread (attachment) – Odtwarzacz plików SID z C64