🔩 QX-11 Integrated Circuit Inventory

This page lists all the integrated circuits (ICs) identified on the Epson QX-11 motherboard, based on direct inspection and documentation.

Column Legend
Part Number – IC marking on the chip
Manufacturer – Chip maker or brand
Function / Description – Role in the system
Package – Physical chip format (e.g., DIP, QFP)
Location / Notes – Placement or additional info

Part Number Description Datasheet QX-11 (Venus Board) QX-16 (APX Board) Equity I (Mars Board)
GAVEMR (E01038EA) Epson VEMR Gatearray nan YES NO nan
HM50256 RAM (512K Max) Download: HM50256 Datasheet (PDF) YES YES NO
GAFDDC (E01037EA) Epson Floopy Controller Gate Array nan YES YES YES
HA16642MF Hitachi Read and Write Circuit for FDD Download: HA16642MP Datasheet (PDF) YES NO YES
GAVNIT (E01045EA) Epson GAVNIT Gate Array (Memory Interrupt Handler ? ) nan YES ? NO
GAVNIO (E01039EA) Epson GAVNIO Gate array (I/O controller ? ) nan YES NO NO
M27256 (EPSON M25140CA & M25141CA) 32Kb EEPROM (64KB total ROM) Download: 27256 Datasheet (PDF) YES YES NO
74HC373 Octal Transparent D-Type Latches Download: SN74HC373 Datasheet (PDF) YES YES YES
SN76489 Programmable Sound Generator Download: SN76489 Datasheet (PDF) YES NO NO
HD146818P Realtime clock plur RAM Download: HD146818 Datasheet (PDF) YES YES nan
74ALS74 Dual Type Flip Flop nan YES ? ?
40H004 Hex Inverter nan YES nan nan
74HC27 Triple Input nor gates nan YES ? ?
74HC245 Octal bus transceiver nan YES ? ?
74LS05 Hex inverter nan YES ? ?
SN74ALS02N Quadruple NOR gates nan YES ? ?
74HC00 Quad NAN gates nan YES ? ?
SN75189AN Quadruple Line receivers Download: SN75189 Datasheet (PDF) YES ? ?
74LS541 Octal buffer and line driver nan YES ? ?
D765AC Single/Double Density Floppy-Disk Controller Download: uPD765AC Datasheet (PDF) YES YES YES
MB3763 Bi-Directional motor driver nan YES ? NO
IJM2903 Precision voltage comparator nan YES ? NO
TL494C PWM Controller Download: TL494 Datasheet (PDF) YES ? NO
TC4584BP Hex Schmitt Trigger nan YES ? ?
SED9421C0B CMOS DATA SEPARATOR FOR FDD Download: SED9420CAC Datasheet (PDF) YES YES YES
KCC 16.000 Crystal nan YES nan nan
KCC 14.31818 Crystal nan YES ? ?
74LS188N Line transmitter 300kbp RS-232 nan YES ? ?
GAVDP (E02032EA) Gate Array Video Display Processor ? nan YES NO NO
HM48416 4-bit Dynamic RAM (48KB VRAM) Download: HM48416 Datasheet (PDF) YES ? ?

📘 This list is subject to revision as more chips are identified or verified.
If you have corrections, please open an issue or submit a pull request.