IC number:	27C64, 2564
IC function:	64 kbit (8k×8) EPROM
Related components:	128 kbit (16k×8) EPROM, 256 kbit (32k×8) EPROM, 1 Mbit (128k×8) EPROM

Component documentation

IC number	Manufacturer	Documentation
NMC27C64	National Semiconductor	Not available
TMS2564	Texas Instruments	Not available

Component versions

IC number	Package	Access time
NMC27C64Q-200	28-pin Ceramic DIP	200 ns
TMS2564JL	28-pin Ceramic DIP

Programmed components

IC number	CBM part number	CBM part description	Chip description	Checksum
NMC27C64Q-200	390230-03		Z80 firmware A2090	2FEF
NMC27C64Q-200	318855-01		Character ROM PC-I	364A
TMS2564JL	251104-04R	2364 ROM Kernal	Kernal ROM SX 64

Positions

Device	Position	Component	Package	Software
A2090A	U36	27C64	DIP	390230-03 (2FEF)
PC-I	U69	27C64	DIP	318855-01 (364A)
SX 64 CPU board	UD3	2564	DIP	251104-04R

Pinout 27C64

Pin	Type	Name
1	Power	VPP
2	Input	A12
3..10	Input	A7..A0
11..13	Output	O0..O2
14	Power	GND
15..19	Output	O3..O7
20	Input	CE_
21	Input	A10
22	Input	OE_
23	Input	A11
24..25	Input	A9..A8
26	N/C	NC
27	Input	PGM_
28	Power	VCC

Pinout 2564

Pin	Type	Name
1	Power	VPP
2	Input	CS1_
3..10	Input	A7..A0
11..13	Output	Q0..O2
14	Power	VSS
15..19	Output	Q3..O7
20..21	Input	A11..A10
22	Input	PD/PGM_
23	Input	A12
24..25	Input	A9..A8
26	Power	VCC
27	Input	CS2_
28	Power	VCC