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Apple-1 Poor Man's Keyboard ^New

Cheap and possibly the smallest keyboard in the world, a real joke.

Set the ASCII data using the DIP switches, press keypress and off you go! A trained finger puts only one character on the screen. The circuit is implemented without debouncing to keep it simple.

It can be a handy thing as well. Onboard clear screen and reset buttons, especially for the Apple 1. Experiment further with the keyboard connector breakout pins. On the backside there is a solder jumper to unhook the 8^th input bit off the 5V, meant for the advanced user. The power out connector can be used to let the computer power the ASCII Keyboard Tester or Character Generator Tester. This keyboard can even be used on top of those!

Licensed under CC BY-NC-SA 4.0

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Apple ][ Poor Man's Keyboard ^New

Yet another one, just as small, just as cheap.

Works the same as the one for the Apple-1. Set the ASCII data using the DIP switches and press keypress. For this one too: a trained finger puts only one character on the screen. No debouncing is implemented. It has an onboard reset button and use the keyboard connector breakout pins for further experiments.

The power out connector can be used to power the other two Testers. Will fit on top of the ASCII Keyboard Tester without the attached One Byte Hex Display only.

Licensed under CC BY-NC-SA 4.0

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ASCII Keyboard Tester

Test vintage parallel ASCII keyboards with ease and see how they actually work.

Eight red LEDs show the data bits coming from the attached keyboard, which contain the ASCII code. The strobe signal can be watched, going high to low, or vice versa. Furthermore, the reset and clear signals can be tested for the Apple 1 and Apple II.

The board needs a 5V power supply as a minimum, but some keyboards need -12V and/or +12V to operate. Onboard is a passthrough power out connector for the keyboard. Connect an Apple-1 or Apple ][ keyboard directly using the DIP-16 connectors. The extra parallel data in connector can be used to connect uncommon or custom keyboards.

Use the bread board area to add your own experiments!

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One Byte Hex Display

Display the hex value (two digits, 0-9, A-F) of any parallel 8-bits TTL input.

To mount it on the ASCII Keyboard Tester, the 74LS374 IC is removed from this tester board. This frees up a socket to put in the display on top. The removed IC is still needed and is being reused on this board. For stand alone usage, the board needs a 5V power supply. Then the data in connector can be used for custom TTL input.

The jumper can be used to enable (or disable) the 8^th bit. This way, both ASCII values (7 bits) and full bytes (8 bits) can be displayed correctly.

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Character Generator Tester

Discover how an Apple-1 or Apple ][ generates a single character for display.

Inspired through the famous article by Don Lancaster, about a tiny self-made display, attached to an ASCII Keyboard (Popular Electronics, issue April 1974). The character is shown on a 5x7 dot matrix display. The binary row address is indicated by LEDs and you can see how the display is being built up by stepping through the 7 horizontal scan lines. The clock speed can be adjusted from 0.6 Hz to 800 Hz.

Connect an Apple 1 or Apple II keyboard directly using the DIP-16 connectors, or use the ASCII data in pins. Verify the ASCII input to the character generator using the character address LEDs. A power supply with +5V and -12V is needed as a minimum. The -5V is regulated on the board itself. Provide +12V when this voltage is needed by the attached keyboard. Supported character generators: Signetics 2513, 2316B, 2716 EPROMs and 2816 EEPROMs. Extra, feed the 8-bit counter output to the ASCII Keyboard Tester!

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