Texas Instruments TI-99/4A – 32k Internal Exp. + Status LED + Reset
Texas Instruments TI-99/4A – 32k Internal Expansion Memory + Status LED + Reset.
Works that have been made:
- 32k Internal Expansion Memory.
- Switch for disable the Expansion Memory.
- Reset Pushbutton switch.
- Bi-Color LEDs to display the status of the internal memory expansion 32k. (ON = Green / OFF = Red)
- Replaced the resistor for the LED from 2.2k to 220 ohms.
Gallery of the works that have been made:
It could be better!
I had severals problems with the free space inside the TI-99/4a, i had to remove one side of the metal part, the biggest problem is the internal 32k expansion which is not very well done, there is no a way to secure it inside … but everything works perfectly :D
Categories: Projects / Repairs, Today, Various
is this 32k upgrade based on harmlesslions 32k internal upgrade ? if so where do you disable the 32k ? i need a switch for mine thanks
@rich
Yes, you have to follow the SPCO (Single pole changeover) colors wires and you find the three contacts on the PCB.