GZ/80S - 20MHz Z-80 PCPI Applicard compatible Apple CP/M card

Submitted by GG on Tue, 04/06/2021 - 14:43

GZ80 B03The PCPI Appli-Card was the first single board computer style CP/M card for the apple II. It featured a 6MHz Z-80 CPU paired with 64KB of RAM and 2KB of ROM. Thanks to the high clock and zero wait states DRAM accesses the card performed almost 3 times as fast as the Microsoft SoftCard. The GZ/80-B00 is a new implementation of the PCPI card with a 20MHz Z-80 CPU and 512KB of static RAM.

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ISO232 - Optically isolated USB to RS232 interface

Submitted by GG on Tue, 03/16/2021 - 16:35

ISO232 A00RS232 are still very popular to control legacy equipment. In industrial settings with long cable runs, interference and different ground references it is necessary to have galvanic isolation. ISO232 is a simple implementation using the FTDI FT230X and opto isolators that can reach speeds up to 115200baud.

Schematics

The schematics is divided in four main portions.

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GRAND - 6Mbps USB True Random Number Generator

Submitted by GG on Sun, 02/28/2021 - 14:48

GRANDA good random numbers generator is fundamental to ensure the security of many modern data encryption algorithms. Depending on the workload, the entropy collected automatically by the kernel might not be sufficient to generate the random numbers at the requested rate. In these cases an external entropy source can greatly improve performance. GRAND is a USB TRNG (True Random Number Generator) based on the ST Microelectronics STM32.

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GZ/80 - Zilog Z80 turbo card for Apple II computers

Submitted by GG on Tue, 01/12/2021 - 13:49

gz80The Microsoft Softcard was the first card to allow CP/M software to run on the Apple II. It was originally developed to simplify the porting of Microsoft Basic to the Apple II. It turned out to be a great success and at some point in time it was the most popular CP/M platform in use.
This success prompted the development of many compatible cards. Some exact copies, some enhanced or cost reduced. The GZ/80 is a modern implementation of a Softcard compatible card with an additional turbo mode with approximately double the speed of the original card.

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Happy 2021!

Submitted by GG on Fri, 01/01/2021 - 00:00

world map2020 was a very unusual year. The COVID-19 pandemic has disrupted many people's life and unfortunately is still ravaging the world. We sincerely hope that 2021 will bring an end to the pandemic and we would like to wish all our customers, friends and suppliers a happy new year. We are very thankful for all the support we received so far and hope to continue in 2021.

NUPS - MCU UPS with NiMH Batteries

Submitted by GG on Wed, 06/17/2020 - 22:44

NUPS A00Many MCU applications are portable and need a mean to provide power on the go. There are many solution based on Li-ION and Li-Polymer batteries. However Lithium chemistries need sophisticated charging and protection circuits to avoid dangerous situations. For lower power projects NiMH batteries provide a simpler and safer alternative. NUPS (NiMH UPS) can provide 3.3V and 5V using 1 to 3 AA or AAA NiMH cells.

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ISO01 - Compact low voltage isolated power supply

Submitted by GG on Sat, 05/23/2020 - 23:14

ISO01 A00While working in the lab it's often useful to have a small isolated power supply handy. Depending on the circuit configuration, ISO01 can generate galvanically isolated unipolar and symmetric voltages from a single 3.3V or 5V rail. The circuit is based on the Texas Instruments SN6501 transformer driver and uses an easy to obtain off the shelf transformer.

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EFM8 Flash - Multi platform GUI Flash tool for Silicon labs EFM8UB1 USB MCUs

Submitted by GG on Tue, 03/10/2020 - 22:11

EFM8 Flash LinuxSilicon Labs makes many excellent 8051 based MCUs. All the MCUs in the EFM8UB line have a native USB and are pre-programmed with a USB HID bootloader. EFM8 Flash is a small GUI tool to flash the MCU from a binary file. The program uses the wxwidgets toolkit for a native look in all supported operating systems and hidapi for cross platform compatibility.

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GTERM25 - DB25 Active SCSI Terminator with diagnostics LEDs

Submitted by GG on Sun, 02/16/2020 - 15:28

GTERMActive termination is required to get newer high performance drives working on vintage computers. Unfortunately both the Amiga and older Apple computers use a DB25 SCSI connector which makes finding a suitable terminator quite difficult. GTERM25 solves this problem providing a high performance active terminator with a DB25 connector and SCSI diagnostic LEDs.

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