I finally designed a printed circuit board; a Z80 Counter/Timer Channels (CTC) module for RC2014.
I’ve only designed a few printed circuit boards in my life, and the most recent of those was about 26 years ago. So my Z80 CTC module for the RC2014 is the first board I’ve designed in a while and the first with modern tools.
The main features of this module are:
- Full Z80 mode 2 interrupt support (IEI/IEO daisy-chain)
- Software control of the baud rate for SIO port B
- Timer and clock tick interrupt
- Source of bus clock (option) to potentially reduce board count
- On-board clock option to make it independent of the CPU clock
- Interrupt mode 2 converter for up to 4 devices
Documentation, including assembly details:
Z80 CTC module User Guide e1.1.0 (PDF)
Z80 CTC for RC2014 Schematic v1.1 (PDF)