A Second Source for the CoCo SDC
The CoCo SDC card for the Tandy/Radio Shack Color Computer.

A Second Source for the CoCo SDC

BoysonTech is proud to announce to be another source for the CoCo SDC*.

BoysonTech will begin selling a limited batch of CoCo SDCs starting Monday, June 22nd. Unfortunately, they are sold without cases. The cases available by mid-July.

The CoCO SDC board (without case) manufactured by BoysonTech is priced at $58. The complete SDC unit (available mid July) will sell at $75. 

Cases will come in black (primary), white, blue and purple (special orders).

Now the CoCo Community has two places to buy this must have product:

Richard Lorbieski (BoysonTech)

https://boysontech.com/marketplace  (website)

https://www.ebay.com/str/boysontech (eBay store)

Ed Snider (The Zippster Zone)

https://thezippsterzone.com/2018/05/08/cocosdc/ (project page)

https://thezippsterzone.com/mpis-coco-sdc-etc/ (store page)

  The CoCo SDC is one of the most sought after upgrade for the Color Computer (CoCo). It has been such a hot commodity that they have appeared on eBay for as much as $200. I contacted Daren Atkinson and obtained permission to manufacture the CoCo SDCs.

  Ed Snider (thezippsterzone.com) has been producing CoCo SDCs for a many years and he makes excellent and quality products. Yet, the demand for CoCo SDCs has sometimes outstripped supply. In the past 2 years, we have seen a huge influx of new CoCo users and unfortunately, these people unknowingly pay these exorbitant eBay prices.

  Moreover, to prevent confusion, I wanted to differentiate my version of my CoCo SDC from Ed’s. It is also a way to prevent unscrupulous people from getting unauthorized warranty repairs/exchanges.

  The solution was to create my version in a different color. I choose ENIG PCBs with matt-black solder mask and gold contacts. Yet, I could only find SDC card modules in blue finish and it looked tacky with the matt-black main board. Thus, I designed the card module from open source schematics.

  As per my agreement with Darren, I pledged NOT to under cut Ed’s prices. In fact, I need to charge a higher price because I use gold plated sockets, connectors and pay eBay listing fees.

From the CoCo SDC manual by Tim Lidner:

     The CoCo SDC is a home-brew project for the TRS80 Color Computer (CoCo). Darren Atkinson began development in 2009. Originally intended to just add floppy disk controller emulation to a Drivewire connection, that idea expanded over time to include emulating a floppy controller for an SD-card reader with Drivewire server access.

     The CoCo SDC aims to solve the compatibility problem by combining the traditional “software hook” approach with a robust emulation of the floppy controller in hardware. This dual mode implementation provides excellent
performance for the majority of software which “plays by the rules” while adding a high degree of compatibility with those titles that employ floppy-based copy protection schemes or simply choose to use their own floppy drivers.

Features and Specifications
• Atmega 328P AVR micro controller @ 10MHz
• Custom 512-byte bootstrap allows firmware to be updated by the CoCo
• 128K In-System-Programmable Flash
• Accepts SD/SDHC cards formatted with FAT16 or FAT32 file system
• Emulates a Tandy Floppy Disk Controller
• Emulate Dragon DOS floppy controllers
• LBA access mode for virtual hard disk support
• Extensions to Disk BASIC in SDC-DOS for disk image manipulation
• Drivewire disk protocol with auto-speed configuration for CoCo 1, 2 or 3
• “Disk Switch” button to support multi-disk programs
• PCB can be mounted in a Tandy FD-502 enclosure

* Darren Atkinson designed and originally produced the CoCo SDC. In 2019, BoysonTech (Richard Lorbieski) obtained permission from Darren to manufacture and sell the CoCo SDC. Ed Snider (https://thezippsterzone.com) has been the primary producer of CoCo SDC for many years.

The CoCo SDC can be directly purchased from this link:

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