Hardware · LED memory map
This is memory map for ZX Spectrum 128k or grey +2 by me & Busy. It can be used also on 48k computers if the bank map part is ommited. You can build it with either 64 LEDs or 8x8 LED segment. Each of LED represents 1kB of memory, so you can see memory region which CPU actually reads - it's very useful for cracking :-)
Part list:
- 3x 74LS138 or MH3205 (clone of LS138)
- 3x 74LS04
- 8x 330R resistor
- 5x 470R resistor
- 6x 100nF ceramic condensator
- 64x 2,5 mm red LED or 1x 8x8 LED segment
- 8x 2,5 mm green LED
- 4x 2,5 mm yellow LED
How to:
Place components to universal board, connect all according schematic. It can be mounted internally or can be built into existing external interface (MB-02+, Betadisk, +D ...). I'm recommending 8x8 segment, which can be obtained in some electronics shop or e-bay or so.
.files.
- schematic diagram: LED-mem-map.png
- sch & brd for EagleCAD (memory map only): LED-mem-map.zip
.galleries.