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The +D (or Plus D) was a floppy disk and printerinterface for the ZX Spectrumhome computer. It was designed to be smaller and more reliable than its predecessor, the DISCiPLE, with fewer ports and steel casing to act as a heatsink. It saw little support from commercial software, but several games were compatible with +D hardware, notably games created by Zenobi Software. It was also used by AlchNews and Outlet, two magazines that covered electronics.
References
"MGT Plus D". Centre for Computing History. Retrieved November 22, 2024.
Woodcock, Colin (2012). The ZX Spectrum on Your PC (2 ed.). p. 40.