Visit https://github.com/matze79/PS2-Adapter for the latest project info (load sch file in online viewer to figure out what the unmarked pads are) BOM as following with Digikey parts:

⋅ R1 - 220ohm 1/4W 1% 0805 (2019-RK73H2ATTD2200FCT-ND)
⋅ R2 - 220ohm
⋅ R4 - 220ohm
⋅ R3 - 10K 1/4W 1% 1206 (RMCF1206FT10K0CT-ND)
⋅ R5 - 2.2K 1/4W 1% 1206 (RMCF1206FT2K20CT-ND)
⋅ R6 - 2.2K

⋅ C1 - 10nF 25V 0805 X5R (445-5984-1-ND)
⋅ C3 - 10uF 25V
⋅ C4 - 10uF 25V
⋅ C5 - 10uF 25V
⋅ C6 - 10uF 25V
⋅ C8 - 0.1uF 50V 0805 X7R (445-7534-1-ND)
⋅* C9 - 0.1uF 50V

⋅ LED1 - 0805 chip LED GREEN Diffused (475-1410-1-ND)
⋅ LED2 - 0805 chip LED RED Diffused (475-1278-1-ND)
⋅* LED3 - 0805 chip LED ORANGE Diffused (475-2488-1-ND)
(If one or more of the LED’s is sold out, you can always use the same color in all 3 spots)

⋅ F1 - Fuse - 30V 125mA 1206 Reset Fuse (F2864CT-ND)
⋅ Y1 - Oscillator - SMD 5X3 8Mhz (XC1897CT-ND)
⋅ IC2 - AT90S2313Microchip Technology AT90S2313 Microcontroller (ATTINY2313A-SU-ND)
(You can also use the ATTINY4313-SU)
⋅ IC3 - Maxim Integrated 16SOIC (MAX232CSE+-ND)
⋅ COM - CONN D-SUB RCPT 9POS (AE10921-ND)
⋅ PS2 Port - 6 pin Mini DIN Female Receptacle (CP-2260-ND)
⋅* USB - USB 2.0 Mini B 5P Connector Receptacle (A135698-ND)