Data Sheet
CPU : 7501 / 8501 @ 1.76 MHz [1]
RAM : 64kB DRAM (Plus/4)
: 16kB DRAM (C16 / C116)
ROM : 48kB ROM total (Plus/4)
: 32kB ROM total (C16 / C116)
Graphics : TED
Sound : TED
Int. drives : -
Interfaces : user port (Plus/4 only)
expansion port,
serial IEC,
TV,
audio/video,
2 x control port,
cassette port
Keyboard : 67 keys (Plus/4)
66 keys (C16)
64 keys C116)
Power supply: external transformer (9VAC + 5V DC) (Plus/4)
external transformer (9V DC) (C16), probably C116, too
Extras : -
![[Picture of Plus/4 board, 55k GIF]](pics/p4pcb.gif)
Schematics
Known revisions: ?
My Plus/4 board has the PCB ASSY #310163. And the keyboard cable is directly soldered onto the board :-(
![[Picture of C116 board, 58k GIF]](pics/c116pcb.gif)
[ Help! Schematics wanted! ]
Known revisions: 5
This board bears the PCB NO #251244 and the ASSY NO 250413 REV 5 (at least that's what I deciphered).
![[Picture of C16 board, 108k GIF]](pics/c16pcb.gif)
[ Help! Schematics wanted! ]
Known revisions: REV.A
This board bears the PCB NO 251789-01, ASSY NO 250443
| Plus/4 | C116 | C16 | |
|---|---|---|---|
| 6529 | U5 & U27 | ? | U13 |
| 555 | U8 | ? | U10 |
| 7406 | U7 | ? | U9 |
| 74LS04 | U6 | ? | ? |
| 74LS08 | U4 | ? | ? |
| ACIA | U3 | ? | - |
| CPU | U2 | ? | U2 |
| DRAM | U11-U18 | ? | U5-U6(?) |
| ROM 251641-02 | U19 | ? | U16 |
| ROM 317053-01 | U25 | ? | ? |
| ROM 317054-01 | U26 | ? | ? |
| ROM 318004-05 | U24 | ? | U4 |
| ROM 318006-01 | U13 | ? | U3 |
| TED | U1 | ? | U1 |
[ Help! Can you fill out the rest? Please VERIFY locations on your board first! ]