guarantee about this.
Cliff Lawson CIS: 75300,1517 Notepad project manager email: cliffl@amstrad.com Amstrad Plc amstrad@cix.compulink.co.uk 169 Kings Road Phone: (+44) 277 208341 Brentwood Fax: (+44) 277 208065 Essex CM14 4EF ENGLAND
I/O Specification for Amstrad NC100
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All numbers are in hexadecimal unless suffixed with a "b" for binary or
"d" for decimal. (Address line numbers A19, A18, etc are in decimal).
SUMMARY
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Address Comment R/W
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E0-FF Not Used - D0-DF RTC (TC8521) R/W C0-C1 UART (uPD71051) R/W B0-B9 Key data in R A0 Card Status etc. R 90 IRQ request status R/W 80-8F Not Used 70 Power on/off control W 60 IRQ Mask W 50-53 Speaker frequency W 40 Parallel port data W 30 Baud rate etc. W 20 Card wiat control W 10-13 Memory management R/W 00 Display memory start W
In Detail
=========
Address = 00 Write only
start address of display memory
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bit 7 A15
Address = 10..13 Read/Write
Memory management control
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10 controls 0000-3FFF
Address = 20 Write only
Memory card wait state control
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bit 7 = 1 for wait states, 0 for no wait
Address = 30 Write only
Baud rate etc.
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bit 7 select card register 1=common, 0=attribute
Address = 40 Write only
Parallel interface data
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The byte written here is latched into the parallel port output register. To
Address = 50..53 Write only
Sound channels period control
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50 channel A period low
Address = 60 Write only
Interrupt request mask
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bits 7-4 Not Used
Address = 70 Write only
Power off control
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bits 7-1 Not Used
bit 0 1 = no effect, 0 = power off
Address = 90 Read/Write
IRQ status
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bits 7-4 Not Used
Address = A0 Read only
Memory card/battery status
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bit 7 Memory card present 0 = yes, 1 = no
Address = B0 - B9 Read only
Keyboard data
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B0..B9 each key of the 64 on the keyboard
Address = C0 Read/Write
UART control/data
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C0 UART data register
Address = D0 Read/Write
Real Time Clock chip (TM8521)
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D0..DC Data
See data sheet of chip for more information.
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NC100 operating system firmware
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notes for external program writers
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To get external programs executed on the Notepad you could either POKE