released

Design is working as expected and has passed all validation testing.

CGA2RGBv2 - Digital RGBI to analog RGB for C128 and IBM PC MDA/CGA/EGA

Submitted by GG on Sun, 05/02/2021 - 22:38

CGA2RGBThe 80 column output of the Commodore 128 is the same digital RGBI used by the original IBM CGA graphics adapter. Unfortunately nowadays is quite difficult to find a monitor with the suitable RGBI input. The CGA2RGBv2 adapter will convert the TTL RGBI to analog RGB suitable to be connected directly to a 15KHz capable RGB monitor or to the popular Gonbes GBS-8200 VGA converter.

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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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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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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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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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NANOBUG - Buttons and USB UART for NVIDIA Jetson Nano

Submitted by GG on Mon, 07/22/2019 - 09:53

NanobugThe NVIDIA Jetson Nano is a great device and its choice of I/O is ideal for user space development. If you are a kernel hacker, however, you will soon feel the need for serial console and a reset button. If you want to hack the bootloader you will also need a recovery button. The Nanobug integrates a UART to USB and buttons into a little board that plugs directly into the nano developer kit.

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UNICART - Universal Commodore 64/128 Cartridge

Submitted by GG on Tue, 06/04/2019 - 20:01

ramgsAfter we developed the UNICART/D many customers asked for a more compact version of the cartridge without the pass-through connector. The board uses one standard PLCC32 flash ROM up to 4Mbit. In C64 mode 8K, 16K and 16K Ultimax cartridge modes are supported. In C128 mode both 16K and 32K cartridges are supported.

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