SmallZ80 Update Log
- 04 Mar 2021
- New EEPROM and CF images (both Z80 & Z180) are posted for download.
The EEPROM HEX files for Z80 & Z180 machines are in the same download -
pay attention to the filenames. The EEPROM code changes reflect an
update to the floppy boot code and an update to the RamTest display
header. The CF modules also reflect changes to the floppy driver,
plus new software (ALFCOPY.COM) that allows copying files to/from the
FAT filesystem on a USB Thumb drive or an SD Card used with the Alfat+2S
expansion adapter (new style adapter only. For old style adapters,
- 22 Feb 2021
- There is a bug in the Z80 EEPROM code v4.00.03. The bug has
been corrected and the new code (v4.00.04, dated 2/22/21) has been
posted. The same 'combined' format with Z180 and Z80 .HEX files is
posted. The Z180 code is unchanged from the .03 version so there's
no need to update a Z180 machine with the v.04 code.
- 21 Feb 2021
- Updated CF images, EEPROM HEX files, and the User Manual are posted
in Downloads. The new BIOS code provides better handling of Floppy
I/O and some bug fixes.
- 08 Jan 2021
- New Z80 Distro EEPROM code and CF image are posted. The
4.00.00 CF was missing the A16: files that are copied to the RamDisk
during the boot process. The EEPROM code was missing a few lines
of code that forced the system to remain in slow speed when J4 was
installed. The Z180 EEPROM code was also affected, but the Z180
does not execute the clock speed change code (all Z180 speed changes are
accomplished via adding/subtracting wait states.) Z180 users will
get the (unneeded) code segment with the next Z180 update.
- 27 Dec 2020
- We're taking orders on the Z180 CPU Upgrade. Shipping will
start Monday, 28 December. We've posted new HEX files for the Z180
and Z80 versions of the EEPROM code (port40 update required!) as well as
an updated User Manual. The CF images for Z80 and Z180 (both Port40!)
systems are now posted. The New-Style Floppy+2S adapter is
tested and ready for shipping. All original I/O Map software and
firmware are final - they will remain available for download but they
will not be updated any further.
- 10 Nov 2020
- The hyperlink for downloading the I/O Map update is restored.
- 7 Nov 2020
- Posted new image for modifying the I/O mapping of the SmallZ80,
moving the ports from a base address of 10H to a base at 40H. The
purpose of the change is to make the SmallZ80 I/O map identical to the
- The SmallZ-180 Production PCB can be seen
The hardware is ready; software is being finalized.
- 7 Aug 2019
- Posted new CF image with corrected BootSet labels.
- 5 August 2019
- New User Manual, CF-IDE image, and EEPROM code are posted for
download. The new code (EEPROM and BIOS v2.02) allows the SmallZ80
to accept Terminal connections via the Internet.
- 11 March 2019
- The SmallZ80 Services and Prices page had been updated.
- 6 March 2019
- The latest v2 CF and EEPROM images are posted in the
downloads section. The
Clock Control Module is available for all Rev E1 CPU boards, and is
required when using the v2 CF and EEPROM software. The new LAN +
ALFAT adapter can provide a connection to either the ALFAT OEM or the
ALFAT USB daughterboard. The only difference is that the ALFAT OEM adds an SD Card
slot and a 2nd USB port to the single USB port on the ALFAT USB.
These adapters allow you to copy files from the FAT-based USB Thumb Drive
or SD Card into the SmallZ80. This is a fast and easy way to get
Internet-based programs, files, and data into your SmallZ80 machine.
Likewise, you can also write your CP/M files directly to the FAT-based
media, which can then be transmitted via e-mail or uploaded to an FTP
site. Both expansion adapters (Floppy and LAN + ALFAT) also provide
a 10/100BaseT LAN connection, used primarily for a lightening-fast 921K
Baud terminal connection.
- One of our customers has created and posted a 6-minute YouTube video
describing the SmallZ80 in operation. You can view it
- 17 December 2018
- The SmallZ80 User Manual has a minor update that reflects comments
received from builders.
- 9 December 2018
- The SmallZ80 is now shipping. User Manual, CF Image, and
distribution EEPROM HEX file are posted. A scan of the production
- 14 November 2018
- We've finalized the design and system configuration. The main
CPU Oscillator has been set to 20MHz with the UART and Slow speed CPU
Oscillator at 14.7456MHz. The Mainboard serial ports are fully
operational and reliable up to 460,800 baud, which makes for a lightening
fast terminal. The Expansion board serial ports can operate up to
921,600 baud, primarily intended for communicating with the LAN processor
for LAN-based terminal and printer I/O.
- Pricing data will be updated within a few days, leading to taking
advanced orders and PCB production within the week.
- 30 October 2018
- The Rev E0 CPU board is tested and updated to the final Rev E1
configuration. Production boards will be ordered within two weeks.
The current oscillator configuration is a 25MHz high speed system
oscillator and a 14.7456MHz UART oscillator, which will also supply the
CPU low speed clock. This configuration will allow baud rates up to
921,800 baud for blazing fast display updates. A new User Manual and
CF image have been posted in the download area.
- 10 October 2018
- The Software/Firmware is undergoing rapid development. The
latest CF and Floppy images, EEPROM Code, and User Manual were recently
- 21 September 2018
- Development continues on the SmallZ80 system. The final hardware
configuration is fairly well developed, with a few minor issues remaining.
A new PCB will be forthcoming soon, which will then be made available to
- 23 August 2018
- The SmallZ80 has completed the initial design and testing phases, and
is shifting into more widespread testing. A few prototype kits are
available for the adventurous. The Floppy + 2S expansion board is
now entering the test and software development process. The SmallZ80
CPU board measures about 6.5" wide x 5" front-to-back. Adding the
dual CF adapter widens the footprint to about 9". The entire system
is powered by a 5v, 2.5A wall wart transformer.
- The LAN option replaces the Terminal and Printer serial I/O ports with
a TCP232-E embedded serial-to-Ethernet module. With the LAN option,
Terminal I/O runs at 230,400 baud with CTS/RTS handshaking for nearly
instantaneous terminal display updates. LAN-based Printer I/O runs
at 115,200 baud without handshaking.