IC number:	µPD765
IC function:	FDC (Floppy Disk Controller)
Related components:	37C65, FDC9268 (FDCs), WD1691 (data separator)

Component documentation

IC number	Manufacturer	Documentation
µPD765A	NEC	Not available

Component versions

Component	Package	Speed	CBM part number	CBM part description
µPD765AC-2	40-Pin Plastic DIP	8 MHz	380206-01	IC LSI FDC UPD765

Positions

Device	Position	Package	Speed
A1060 main board	U31	DIP	8 MHz
PC-10 combined board	U64	DIP	8 MHz
PC-10 I/O-board	U12	DIP

Pinout

Pin	Type	Name	Description
1	Input	RESET_	Reset input
2	Input	RD_	Read control input
3	Input	WR_	Write control input
4	Input	CS_	Chip select input
5	Input	A0	Data or status select input
6..13	I/O	DB0..DB7	Bidirectional data bus
14	Output	DRQ	DMA request output
15	Input	DACK_	DMA acknowledge input
16	Input	TC	Terminal count input
17	Input	INDEX	Index input
18	Output	INT	Interrupt request output
19	Input	CLK	Clock input
20	Power	GND	Ground
21	Input	WCLK	Write clock input
22	Input	WINDOW	Read data window input
23	Input	RDATA	Read data input
24	Input	SYNC	VCO sync output
25	Input	WE	Write enable output
26	Output	MFM	MFM output
27	Output	SIDE	Head select output
28..29	Output	US1..US0	FDD unit select output
30	Output	WDATA	Write data output
31..32	Output	PS1..PS0	Preshift output
33	Input	FLT/TRK0	Fault / track 0 input
34	Input	WPRT/2SIDE	Write protect / two side input
35	Input	READY	Ready input
36	Output	HOLD	Hold load output
37	Output	FLTR/STEP	Fault reset / step output
38	Output	LCT/DIR	Low current / direction output
39	Output	RW_/SEEK	Read/write / seek output
40	Power	VCC	DC power (+5V)