TEC-1G SD Card Interface and 8bit Input/Output GPIO Module

Micro SD Card

Back in the day, the TEC-1 only had a Tape interface to save or restore your programs. Today, most would not know what a cassette tape looks like, let alone own a working deck. Today is all about the SD Card, and that's what this module gives to the TEC-1G.

Note that the MON3 currently does not have the API to make use of the SD Card, but it is currently in development. Keep an eye on the GitHub for new versions that support the SD. There is currently some rudimentary test code and of course you could always help by developing something for the community.

General Purpose Input & Output

But this module also has a secondary purpose; Ever wanted to control things out in the real world, like a robot arm, or some water sprinklers? Ever wanted to make your TEC-1 work like an alarm system, with movement detectors and reed switch inputs and siren outputs?

Well you can't do that directly; you need relays, and this is the board that lets you control relays and also take up to 8 inputs from switches and sensors. Your imagination really is the limit once you have this interface to the real world.

And the best thing is if you need more than 8 inputs or outputs, you can stack up to three (3) of these units on top of each other, each with its own Port address. That gives you up to 24 input/outputs!

Kit Options

Included in the base Kit:

• 1x Custom made PCB
• 1x 8pin x 2rows long legged wire wrap socket
• 1x 2pin long legged wire wrap socket
• 2x 10pin female header connector, right angled
• 1x 3pin x 2rows (6) header pins, right angled
• 2x 20pin DIP socket
• 1x 14pin DIP socket
• 1x 330R resistor
• 1x 3mm Red LED
• 1x 100n capacitor
• 1x 74HCT245
• 1x 74HCT32
• 1x 74HCT273

Micro SD Card Module

• If you will use this module only for general input and output, you may not need the SD Card module.

Testers

The "Testers" are used for exactly that: Testing the inputs and making sure outputs are as expected while developing your code. If buying multiples of this kit, you probably only need one set of testers.

Testers include:

• 2x mini PCBs
• 2x 10pin male header strip, right angled
• 1x 10K resistor network
• 1x 8pole DIP switch (for the input tester)
• 1x 8Bar LED module (for the output tester)

TEC-1G Connectors Option

If you purchased a full TEC-1G kit up to June 2025, you would have ALL the connectors included, and thus DON'T need the expansion connectors added. However, in an effort to reduce the initial cost of the base kit (and to make it less arduous on the initial soldering), only the essential connectors were included in the base TEC-1G kit from July 2025. Also, if you pulled the parts together yourself and didn't bother with the connectors, then you can buy the required connectors for the TEC-1G motherboard as an add-on to this kit.

This policy will be extended to all Expansion Kits, but you only need to add this on ONCE for each group of expansion boards, not with EVERY Expansion Kit you purchase. The SD Card uses the GPIO expansion slot, so this Kit Option gets you:

• 1 x 20 pin (2x10) female vertical socket (GPIO bus)
• 1 x 2 pin female vertical socket (Power)