250477
- Released in 1986
- PCB Number 250477.
- Schematic Number 252451.
- The Board has an improved 80 column mode video chip over the normal C128
- the integrated 1571 drive is less compatible than the stand alone 1571 as the WD1770 and CIA are combined in one chip
Integrated Circuits
| U1 | 6526 | CIA 1 | $DC00 |
|---|---|---|---|
| U2 | 4066 | Quad Bilateral Switch | |
| U3 | 74LS138 | Decoder/demultiplexer | |
| U4 | 6526 | CIA 2 | $DD00 |
| U5 | 8580 | SID | $D400 |
| U6 | 8502 | CPU 6 MHz | |
| U7 | 8722 | MMU | $D500 |
| U9 | 74F32 | Quad 2-input or gate | |
| U10 | Z80B | CPU 6 MHz | |
| U11 | 8721 | PAL | |
| U17 | 74ALS373 | Octal Latch | |
| U18 | 2364 | Char ROM | $D000-$DFFF |
| U19 | 2016 | 2k x * SRAM | $D800 |
| U20 | 4066 | Quad Bilateral Switch | |
| U21 | 8564 NTSC 8566 PAL | VIC II | $D000 |
| U22 | 8568 | 80 COL CRT CNTRL | $D600 |
| U23 | 4464 | 64K x 4 DRAM Video | D0-D3 |
| U25 | 4464 | 64K x 4 DRAM Video | D4-D7 |
| U27 | NE556 | Dual Timer | |
| U28 | 8701 | Clock Generator | |
| U32 | 27256 | ROM Basic | $4000-$BFFF |
| U34 | 27256 | c64 kernal and basic + c128 kernal | C64 $A000-$BFFF $E000-$FFFF C128 $C000-$CFFF $E000-$FFFF |
| U36 | 23256 | Function Mem/Rom | |
| U38 | 41254 | 64K x 4 DRAM | D0-D3 |
| U39 | 41254 | 64K x 4 DRAM | D4-D7 |
| U40 | 41254 | 64K x 4 DRAM | D0-D3 |
| U41 | 41254 | 64K x 4 DRAM | D4-D7 |
| U55 | 74F245 | Octal bus transceiver | |
| U102 | 27256 | ROM DRIVE | $8000-$FFFF |
| U103 | 2016 | 2k x * SRAM | $0000-$07FF |
| U104 | 6522A | VIA 1 | $1800-$180F |
| U106 | 6522A | VIA 2 | $1C00-$1C0F |
| U107 | 5710 | FDC (intergrated WD1770 and CIA) | $2000-$2005 $400C-$400E $4010-$4017 |
| U108 | CX20185/MC28719/LA8200 | FDD R/W AMP | |
| U109 | UPA2003C | NEC |
Schematics
Schematic 252451, sheet 1 of 5
Schematic 252451, sheet 2 of 5
Schematic 252451, sheet 3 of 5
Schematic 252451, sheet 4 of 5
Schematic 252451, sheet 5 of 5
Board Image
