LK1,LK2,LK3 connect to [[8255|PPI]] Port B, Bit1-3. The links select the manufacturer name (which is displayed by the BIOS in the power-up message). These LKs exist on all CPC mainboards (in CPC Plus/GX4000 schematics they are named LK101,LK102,LK103). By default, LK1-LK3 are not installed (Amstrad). Other combinations are LK2 installed in german [[Schneider]] models, and LK1+LK2 in australian [[Awa]] models.
{|{{Prettytable|width: 700px; font-size: 2em;}}
|''Bit 3 (LK3)''||''Bit 2 (LK2)''||''Bit 1 (LK1)''||''Manufacturer Name''
|-
|0||0||0||[[Isp]]
|-
|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)
|-
|}
Note: "0" means LK installed.
== LK4 - Screen Refresh Rate ==