Vermes
Advanced Member level 4
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
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