This is a small cased eZ80 system that comes built and tested with CP/M 2.2. It uses the fastest Zilog processor which includes an integrated EMAC that makes it ideal for Zilog aficionados wanting to incorporate an Ethernet interface.

While the eZ80 is Z80 code compatible, it has a much enhanced instruction set (Z180 + 16MB addressing + IX/IY H/L etc) and is MUCH faster. I've run a few benchmarks in which this system was roughly equivalent to a Z80 at about 170-195 MHz and roughly 4.4 to 5 times faster than a Z180 at 33 MHz, depending on instruction mix.

Case Size: 80mm x 40mm x 20mm or approximately 3.15" x 1.57" x 0.79"

N.B. Please DO NOT order a USB Smart Cable unless you plan to do serious low-level debugging that can't be handled by a software debugger. The price of new cables (i.e. ZUSBASC0200ZACG) has gone way up but occasionally I locate some new or used Smart Cables which I test and make available. My supply is VERY limited and it's not required for normal operation!

Features:

• Zilog eZ80F91 AcclaimPlus! at 50 MHz
• 256KB of internal flash memory for boot code, CP/M 2.2 and a 224KB "disk"
• 512KB to 4MB of zero-wait SRAM or 512KB / 2MB SRAM + 512KB / 2MB MRAM (N.B. Versions)
• 16MB of byte-wide serial flash as two 8MB resident flash drives
• Two USB serial ports at 115200 baud with RTS/CTS handshaking
• 10/100 Mbps Ethernet interface
• MicroSD socket with SPI interface at 8.3MHz
• 256 bytes of EEPROM available to user programs
• Real Time Clock (RTC) with rechargeable battery
• RUN (green) / HALT (red) bicolour LED
• Two user-programmable LEDs
• A RESET pushbutton
• USB powered

Versions:

• There are two main variants based on the optional second parallel memory device: one that supports a second SRAM and one whose second device is a non-volatile MRAM. These use different PCBs which are basically identical except for the layout of the second memory device.

Included in purchase:

• An assembled and tested system as described above and similar to the one pictured. Since most components are SMD, these systems are not being offered as bare boards or kits.
• A new 16GB or larger microSD card and adapter with an 8MB CP/M partition and a FAT32 partition with documentation including the BIOS & CP/M source code plus schematic & datasheets and approximately 7.5GB of CP/M-era software including various application programs, CPMUG, Dr. Dobbs Journal, SIG/M, The Computer Journal, etc.

Required items:

• A host computer with a USB port plus a terminal emulation program such as HyperTerm or TeraTerm
• A USB A to mini-B cable or adapter
• Silicon Labs USB to UART VCP (Virtual COM Port) driver which is automatically installed by Windows or downloadable from their website with versions for Linux, Android etc.

Optional items:

• A Zilog Smart Cable can be used for debugging but is NOT required since these systems contain a flash loader. Smart cables such as the USB version (ZUSBASC0200ZACG) are available from suppliers such as Digi-Key or Mouser and use of the Zilog Debug Interface (ZDI) will require the user to install the supplied header.

Status:

• No hardware issues have been identified at this time and there has been no reports of software problems. It's possible that some software anomalies may remain and the complete BIOS source code is included. This BIOS can be re-assembled using Zilog's ZDS II for eZ80Acclaim! (free download from their website) and updated using the preinstalled loader.
• The Ethernet connection on all systems has been tested at 100 Mbps / full-duplex using Zilog's AN0212 between two of these systems. At this time the BIOS does not include any Ethernet code although two such projects are underway.
• BIOS enhancements to support flash wear leveling and to allow multiple SD "disks" are also in development and updates will be made available to purchasers.

Availability:

• Only a limited set of memory options are being offered but any unpopulated memory positions are upgradable.

TRS-OS:

• This device has been tested with TRS-OS for those people who would like to run LS-DOS programs at up to 50 times their original speed. TRS-OS was not developed by CircleM Systems and more information is available by following this Link or here on Facebook. In order to run TRS-OS, it will require Min-eZ BIOS V0.4 or V1.x

Shipping and handling:

• Canada post is currently on strike. I have alternate ways to ship to Canada and the USA but purchasers from other countries will need to contact me about possible alternatives and costs.

• Shipping is via Canada Post and includes tracked airmail within Canada and USA or NON-TRACKED airmail for other countries. Tracking outside Canada and USA is an optional extra and if the purchaser doesn't choose it, they accept the liability for any lost packages. Not all countries support small packet tracking so if in doubt, please send an inquiry message to the seller. Any taxes and/or duties are the responsibility of the purchaser.

Disclaimer:

• These systems and their software are for hobbyist use only. They have been assembled on a reasonable efforts basis and are tested as working before shipment.
• The seller is the original designer / builder of these systems and the author of the BIOS.