Item |
Original |
Suggested |
CPU Section |
IC22 |
CPU |
||
IC23 |
74LS138 |
|
Decodes 4K memory blocks in top 32K |
IC44 |
74LS393 |
74HCT393 |
Binary counters |
IC9, IC45 |
74LS04 |
74HCT04 |
Inverters for clock oscillators, reset, etc. |
IC7 |
74LS02 |
|
Helps detect first 1K |
IC8,48 |
74LS00 |
|
|
IC49 |
74LS139 |
|
I/O decoder |
X4 |
4.000 MHz |
|
Quartz crystal |
|
|
|
ROM and RAM |
IC10-19,51,52 |
6264 or 62256 | 6K, 8K or 32K RAM |
|
IC6 |
74LS138 |
Decoder for 2114 chips |
|
IC20 |
MM52164 |
27128 | |
IC21 |
MM52132 |
4K (EP)ROM at 0xDXXX Atom Floating Point |
|
IC24 |
MM52132 |
2732 (not pin compatible ) |
4K EPROM at # AXXX Utility ROM |
|
|
|
Keyboard and I/O |
IC1 |
65C22 |
User I/O and/or printer port |
|
IC50 |
74LS244 |
74HCT245 |
Printer port buffer |
IC25 |
82C55 |
PPI |
|
IC26 |
7445 |
|
Keyboard column decoder |
|
|
|
Tape interface |
IC46 |
LM358 |
|
Op-Amp for tape input |
IC47 |
74LS161/163 |
74HCT161/163 |
Counter for tape interface |
|
|
|
Expansion bus |
IC2 |
8304 |
74HCT245 |
Expansion bus data buffer |
IC3,4 |
81LS95 |
74HCT245 |
Expansion bus address buffers |
IC5 |
74LS30 |
|
Expansion bus buffer enable |
|
|
|
Video section |
IC31 |
|
CRT controller |
|
IC30 |
74LS138 |
6264 | Decoder for 2114 chips |
IC32-43 |
Video RAM |
||
IC27,28 |
81LS95 |
74HCT245 |
Video RAM address buffers |
IC29 |
8304 |
74HCT245 |
Video RAM data buffer |
X1 |
3.575945 MHz |
|
Quartz crystal |
|
|
|
Power |
IC53,54 |
LM340T-5 |
|
5V regulators |
C12 |
22 uF |
|
Input voltage capacitor |
C13 |
22 uF |
|
5V decoupler, LF |
C14-28 |
47 nF |
|
5V decouplers, HF |
|
|
|
Misc |
L1 |
1 mH |
|
Choke |
SK1 |
|
|
UHF modulator |
SK2 |
7-pin DIN |
|
|
SK3 |
|
|
Power socket |
Q1,Q2 |
BC107 |
|
NPN transistors |
C1,6,10 |
10 nF |
|
|
C2-5, 8,12,13 |
22 uF, > 10V |
|
LF decoupling |
C7 |
47 or 100 nF |
|
|
C9 |
22 or 47 nF |
|
|
C11 |
10 uF |
|
|