Bug fix: the "ghost RTC"

A project log for A 4$, 4ICs, Z80 homemade computer on breadboard

No iron, no cry! Build a mini 4MHz Z80 64kB RAM system with Basic and Forth interpreters, CP/M 2.2, QP/M 2.71, Assembler and C toolchains

Just4FunJust4Fun 02/10/2018 at 17:010 Comments

Reading this Japanese article on a kit sold in Japan to build a Z80-MCB, I realized the presence of a possible bug seeing this two images:

As you can see, there is a Z80-MCB without any Virtual Disk or RTC attached and in the resulting screenshot the RTC appears present.

After a quick check I found a little bug in the RTC discovery routine that see a "ghost RTC" when the Virtual Disk is not present.

So I've uploaded a new "sketch" (S221116_R100218_Z80.ino) that fix the bug.

Note that if you have the Virtual Disk already installed, there isn't any real need to upgrade.