ISO02 - Low Voltage Isolated Power Supply for Arduino

ISO02 A00While working with Arduino in industrial applications it's often useful to have a isolated voltages available. Depending on the circuit configuration, ISO02 can generate galvanically isolated unipolar and symmetric voltages from the 5V Arduino power. The circuit is based on a basic push pull configuration and uses an easy to obtain off the shelf transformer.

Schematics

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A2SCSI-A02 - Apple II SCSI card clone

A new version of this project is available here

A2SCSI FrontThe Apple II SCSI card from 1986 was one of the first interface cards to attach a Hard Disk Drive to the Apple II line of computers. A2SCSI is a clone of the last revision (rev.C) of the card with a few enhancements to improve compatibility with modern SCSI drives.

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M100ROM - 27C256 adapter for Tandy Model 100

M10ROMThe Tandy TRS-80 model 100/102 and 200 provide a ROM socket to add built in programs to the machine. To make inserting and replacing the ROM more user friendly the designers choose to use a custom chip socket (Molex series 78805) with 700mils pitch. The Molex carriers that mate with the sockets have been out of production for many years and are nowadays impossible to obtain.

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GGLABS Kiva Loans update

Kiva mapGGLABS started lending on Kiva back in 2016 and we are proud to announce that we have just made our 400th loan for a grand total of $10,000 of loaned funds. We love to support entrepreneurs and small businesses around the world to improve their lives. During the years we have supported people from 66 different countries.

6502 C Compilers Comparison

C6502C is our favorite language as it provides reasonably high level constructs while maintaining very good performance. The majority of the code we write for for both vintage computers and microcontrollers computers is in C. In this article we compare several C compiler for the 6502 to understand the performance and limitations of each.

SDCC 4.2.0 Released

SDCC logoA new release of SDCC, the portable optimizing compiler for STM8, MCS-51, DS390, HC08, S08, Z80, Z180, Rabbit, SM83, eZ80 in Z80 mode, Z80N, TLCS-90, 6502, Padauk and PIC microprocessors is now available. Sources, documentation and binaries for GNU/Linux amd64, Windows amd64, macOS amd64 and Windows x86 are available.

GS2HD - Apple IIgs RGB to HDTV Component Adapter

GS2HD E01The apple IIgs, like many computers from the 80's and early 90's, has a analog RGB output at a 15KHz horizontal frequency (same as NTSC/PAL). The majority of modern monitors and TVs will not sync to anything below 31.5KHz on their VGA input. If you have a TV with a SCART connector it is possible to wire the RGB directly to the TV. Most TVs in USA, however, use the YPbPr component instead of SCART making a direct connection not possible.

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