Synthechnics

EF68B09, MC68B09 8 bit processor

Elka EK22, EK44, Oberheim Matrix 1000, Sequential Prophet 2000

HD63B03RP 8 bit processor

Cheetah MS6, Korg DW-8000

M50734SP CPU

used in Kawai R100, R50, R50e, Cheetah MD16

P8031 Intel CPU

Used in Kawai SX-210, SX-240, Roland Jupiter 6, JX-8P, JX-10, JX-3P, MKS-70, MKS-80, Crumar Bit One, Bit 01, Bit 99

P8032AH CPU

Used in Roland Alpha Juno 1 and 2

R6502P Rockwell 8 bit processor

used in Elka Synthex

TMS7000NL-2

Siel DK 70, DK 80, EX 80, DK600, DK700, Opera 6, Elka OMB-5, Drumstar 64, Drumstar 80, Jen Synx 508.
Attention: Siel Synthesizers mostly use TMS7000N2L-2 which has a 1.778mm pin pitch. Jen Synx 508 also used the small pitch version.

TMS7001NL-2

Elka EK22, EK44, EM22, EM44, ER44, ER33 processor

TMS7002NL

Solton TS4K, TS4, TS3K, TS3, K160, Keytek (Siel) CTS-2000, Elka OMB3

Zilog Z80 CPU

You should also check my Z80 CPU tester

used in Sequential Drumtraks, Prophet 5, Prophet 10, Prophet 600, Moog Memorymoog, Roland Jupiter 8, Oberheim OB-8, E-mu Emulator I and II, SP-12, SP-1200, Drumulator, Linn LM-1, Linndrum and so many more...

MSM80C85ARS - 8 bit Microprocessor

Used in Korg Poly-800/Poly-800 II