Micro SwinSID Firmware Version 20100430

- much improved sound of combined waveforms

*Note - This is old firmware, just here for history.

Micro SwinSID Firmware Version 20101019

Here is the new test firmware for ATmega88 with recent fixes merged from 8515 version.
Not tested on a real device!

*Note - This is old firmware, just here for history.  File and comments are from this post at forum64.de

Micro SwinSID Firmware Version 20110110

Here is new minor firmware update for Micro SwinSID ( ATMega88 ) with following changes:
- much improved ADSR envelope fading based on a real SID counter design
- more soft filter

 Hardware tip:

- to increase audio quality and volume level replace R4 (2k2) resistor with 1K. This will boost volume by about 50%

Micro SwinSID Firmware Version 20110227

This new firmware brings 6581 filter emulation by connecting B0 AVR pin to ground.
Filter distrortions are still not emulated, only filter cutoff is affected.

*Note - This is old firmware, just here for history.  File and comments are from this post at forum64.de

Micro SwinSID Firmware Version 20120524

This version has only one improvement: fixed audio muting emulation

As of August 2019, this is the most recent version of the firmware for the Micro SwinSID

Here is the schematics and PCB layout of the Micro SwinSID based on ATMEGA88. This is minimalistic version of SwinSID. It contains only clock generator, AVR, few resistors and single voltage filtering capacitor. To minimize complexity it was designed to work only with C64 internal output. This remains original output stage already tested by Crisp. PWM lowpass filtering is done in C64 by RC filter before the output transistor.

Micro SwinSID PCB v1.1 - This schematic and information was pulled from this post on forum64.de