RC2014

Created: 2024-08-31

I'd thought about building one of these for years, and the announcement of the Z80's retirement spurred me to finally buy one. I went with the 64K Pro kit. I added the blue box that is supported for some Zed model add-ons. I considered others, but the Altair-like color is striking. I mounted the PCB directly to the bottom of the case with standoffs, and made custom front and back panels with 3d printing.

Front Panel

The red button and red LED bargraph are Adafruit parts, the switch is from American Science and Surplus. I had them on hand already. The LEDs are currently indicating, from top to bottom: power, CF card activity, serial port receive line and serial port transmit line (updated after the photo). I modified the CF interface to put the activity signal on an unused bus line. A custom card to breaks out the signals for the front panel, with a buffer on the serial lines so that the LED power draw doesn't interfere with communication.

Inside

I added a resistor to the clock generator to get the reset working at 7.4MHz, but the 4MHz setting still seems to be more stable and is more compatible with software for vintage machines. I replaced the reset button on the card with a 90-degree header to connect the front-panel button.

Rear

A panel-mount barrel jack on the back panel provides 5v power. I used a RS232 level-shifting breakout board to put a 9-pin serial port on the back panel, wired the same as a PC.

Release	2014
OS	CP/M 2.2
CPU	Z80 0.3Mhz-7.4MHz
RAM	64K
Internal Storage	64K ROM, 128MB CF Card
Case	9.8 x 7.5 x 4.3 inch blue project box Amazon