|5||/EXP||Expansion Port /EXP pin||Same as on CPC
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|4||LK4||Screen Refresh Rate ("1"=50Hz, "0"=60Hz)||Purpose unknown (not same as on CPC?) (set Set to "1"=50Hz (but ignored by the KC BIOS, which always uses 50Hz even if LK4 is changed)
|-
|3||LK3||Manufacturer rowspan="3" |Distributor ID bit3, see [[LK selectable Brand Names]] for details. Usually set to [[Amstrad]], [[Awa]], or [[Schneider]]||Purpose unknown (set to "1")
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|2||LK2||Manufacturer ID bit2||Purpose unknown (set to "0")
* Bit5 (/EXP) can be used by a expansion device to report it's presence. "1" = device connected, "0" = device not connected. This is not always used by all expansion devices. ''is it used by any expansions?'' [in the DDI-1 disc interface, /EXP connects to the ROM bank selection, bank 0 or bank 7]
* For more info see [[LK Links]] Table showing manufacturer name on powerLK1-up LK4 (CPC and CPC+ onlyfurther LKs): {|{{Prettytable|width: 700px; font-size: 2em;}}|''Bit 3 (LK3)''||''Bit 2 (LK2)''||''Bit 1 (LK1)''||''Manufacturer Name'' |-|0||0||0||see [[IspLK Links]]|-|0||0||1||[[Triumph]]|-|0||1||0||[[Saisho]]|-|0||1||1||[[Solavox]]|-|1||0||0||[[Awa]] (australian CPCs)|-|1||0||1||[[Schneider]] (german CPCs)|-|1||1||0||[[Orion]]|-|1||1||1||[[Amstrad]] (default)|-|}
== PPI Port C ==