ATTiny2313 24 channel servo controller schematic
Here is a schematic for a 24 channel version of the ATTiny2313 servo controller. You can expand the number of channels up to the full 64 by adding additional CD74HCT238Es where each additional MUX chip is connected to the next available pin on port b.
ATTiny2313-24ChannelServoController.png The schematic, in Eagle format, is here: ATTiny2313-24ChannelServoController.sch and a potential board layout is here: ATTiny2313-24ChannelServoController.brd These were produced with Eagle and I don’t think I could have worked out how to use Eagle without reading Build Your Own Printed Circuit Board by Al Williams.