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|#FBDF||?||[[Amstrad Serial Interface]] 8253 Timer Modus Select|| - ||Write
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|#FBxx||?||[[Real Time Clock]] (DIY)||?||?
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|#FBE0 - #FBE3||?||[[Dk'tronics Real Time Clock]]||?||?
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|#FBE0||?||Hard Disc Data Port||Read||Write
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|#FBE4||?||Hard Disc Reset||Read||Write
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|#FBxx||?||[[Real Time Clock]] (DIY)||?||?
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|#FBE0 - #FBE3||?||[[Dk'tronics Real Time Clock]]||?||?
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|#FBE6||?||Port B - [[IDE8255]]||?||?
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|#FBE8||?||[[Dk'tronics Real Time Clock]]||?||?
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|#FBE8||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 8253 Timer0 (RX Clock)||?||?
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|#FBE9||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 8253 Timer1 (TX Clock)||?||?
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|#FBEA||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 8253 Timer2 (not used)||?||?
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|#FBEB||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 8253 Timer Control||?||?
|-
|#FBEC||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 6850 (reversed bit-order) Control||-||Write
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|#FBED||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 6850 (reversed bit-order) TX Data||-||Write
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|#FBEE||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 6850 (reversed bit-order) Status||Read||-
|-
|#FBEF||?||[[KDS_Electronics_Serial_Interface|KDS RS232]] 6850 (reversed bit-order) RX Data||Read||-
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|#FBEE||?||[[Amstrad SSA-1 Speech Synthesizer]]||Read||Write