
This is an update on the development of the z80 computer emulator.
Info: https://newbrainemu.eu/2025/12/14/atlas-z80-computer-emulator/
Github: https://github.com/cdesp/Z80_SBC
12/6/2026
You can see some jumper cables because the 16 bit voltage translators 74LVC16245 work with reversed the directional pins compared to the 74LVC4245(8 bit ones) and i didn’t RTFM so i had to reverse 3 pins to make it work as expected.
So far i manage to have
- the serial RS232 working via a USB-C connection to my PC at 115200bps.
- The 1MB SRAM
- The FPGA has 8KB internal RAM that i currently use to load z80 code to boot.
13/6/2026

- The Flash Ram works i got the id 0xBF,0xDF (SST39LF040)

- Video signal works from HDMI output. I am using an HDMI to VGA converter.
22/6/2026

Fixing the databus enable signal for the databus voltage converter. I had to use a 74hct32 ic to include the 3 devices that are accessed by the z80 directly (ch376s, AY38912 and SN76489).
I am currently working on the usb storage device (CH376s) so i can read files from there.
24/6/2026
Developing is going great. Storage device is working and the Video signal is ok for the default screen 320x200x4 of the bootloader.
