Lomax ColorMagic Redux
About the Lomax ColorMagic Redux PCB
Lomax ColorMagic Redux is an open source PCB design by RichCini, published on GitHub. It is a 4-layer board measuring 254 × 137.7 mm, with 148 components from 72 distinct parts.
Other key parts include the PAL16L8, 74LS273, 74LS153, 74LS166 and 74LS393. By type, the board carries 69 ICs, 39 capacitors, 16 jumpers, 16 resistors, 5 connectors and 1 transistor.
From the project
Small repository of files/data related to Lomas Data Products S-100 boards.
To make the correction on existing 1.1-005 boards, it requires lifting pin 20 of each SRAM (CS*) and connecting it to ground, and lifting pin 26 (A13) and connecting to MA13 (pin 20 of the socket). I did this with some 30AWG wire- wrapping wire soldered to the tops of the pins in question.
There is also a revised versions of the U18 and U55 PALs that's recommended for all users. Again, the update to U18 is related to discoveries made in debugging Mode 6, while the update to U55 is related to a discovery by Patrick Linstruth that the MS-DOS RTC was running fast. The 8253 timer was not being…
Main components on the Lomax ColorMagic Redux
Lomax ColorMagic Redux bill of materials (BOM)
148 components, 72 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 3 | PAL16L8 | DIP-20_W7.62mm_Socket | U1, U18, U61 |
| 3 | 74LS273 | DIP-20_W7.62mm_Socket | U2, U5, U24 |
| 2 | 74LS153 | DIP-16_W7.62mm_Socket | U3, U15 |
| 3 | 74LS166 | DIP-16_W7.62mm_Socket | U4, U27, U50 |
| 1 | 74LS393 | DIP-14_W7.62mm_Socket | U6 |
| 2 | HM62256BLP | DIP-28_W15.24mm_Socket | U7, U8 |
| 1 | 74LS08 | DIP-14_W7.62mm_Socket | U9 |
| 1 | 74LS367 | DIP-16_W7.62mm_Socket | U10 |
| 11 | 74LS244 | DIP-20_W7.62mm_Socket | U11, U39, U40, U41, U44, U45, U47, U48 +3 |
| 1 | 74LS151 | DIP-16_W7.62mm_Socket | U12 |
| 6 | 74LS74 | DIP-14_W7.62mm_Socket | U13, U36, U53, U63, U64, U65 |
| 1 | LM7805K | TO-3 | U14 |
| 2 | PAL20L10 | DIP-24_W7.62mm_Socket | U16, U55 |
| 3 | 74LS174 | DIP-16_W7.62mm_Socket | U17, U29, U38 |
| 4 | 74LS04 | DIP-14_W7.62mm_Socket | U19, U28, U30, U32 |
| 1 | 74LS175 | DIP-16_W7.62mm_Socket | U20 |
| 1 | 74LS86 | DIP-14_W7.62mm_Socket | U21 |
| 1 | 74LS02 | DIP-14_W7.62mm_Socket | U22 |
| 1 | 2764 | DIP-28_W15.24mm_Socket | U23 |
| 1 | 82C55A | DIP-40_W15.24mm_Socket | U25 |
Show 52 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | MC6845 | DIP-40_W15.24mm_Socket | U26 |
| 1 | 74LS32 | DIP-14_W7.62mm_Socket | U31 |
| 1 | 74LS00 | DIP-14_W7.62mm_Socket | U33 |
| 2 | 74ALS174 | DIP-16_W7.62mm_Socket | U34, U46 |
| 1 | 74LS164 | DIP-14_W7.62mm_Socket | U35 |
| 1 | 74LS322 | DIP-20_W7.62mm_Socket | U37 |
| 3 | 74LS373 | DIP-20_W7.62mm_Socket | U42, U43, U60 |
| 1 | LM78L12 | TO-92L | U49 |
| 1 | 74125 | DIP-14_W7.62mm_Socket | U51 |
| 2 | 74LS14 | DIP-14_W7.62mm_Socket | U52, U62 |
| 2 | 74LS688 | DIP-20_W7.62mm_Socket | U54, U56 |
| 1 | 7406 | DIP-14_W7.62mm_Socket | U66 |
| 1 | 74LS92 | DIP-14_W7.62mm_Socket | U67 |
| 1 | 8253 | DIP-24_W15.24mm_Socket | U68 |
| 1 | 74LS38 | DIP-14_W7.62mm_Socket | U69 |
| 1 | 2N3904 | TO-92 | Q1 |
| 1 | 14.31818MHz | Oscillator_DIP-14 | X1 |
| 1 | CGA Out | PinHeader_2x05_P2.54mm_Vertical | J1 |
| 1 | RCJ-014 | CUI_RCJ-014 | J2 |
| 1 | Keyboard | PinHeader_1x05_P2.54mm_Vertical | J3 |
| 1 | LPEN | PinHeader_1x06_P2.54mm_Vertical | J4 |
| 1 | S100_MALE | S100_MALE | P1 |
| 1 | Options | PinHeader_1x08_P2.54mm_Vertical | JP1 |
| 5 | Jumper_2_Open | PinHeader_1x02_P2.54mm_Vertical | JP2, JP3, JP4, JP5, JP402 |
| 1 | Address | PinHeader_2x08_P2.54mm_Vertical | JP6 |
| 1 | Sync | PinHeader_1x03_P2.54mm_Vertical | JP7 |
| 1 | CLK Polarity | PinHeader_1x03_P2.54mm_Vertical | JP8 |
| 1 | HIADDR | PinHeader_1x03_P2.54mm_Vertical | JP9 |
| 1 | Interrupts | PinHeader_1x10_P2.54mm_Vertical | JP10 |
| 1 | ID | PinHeader_1x12_P2.54mm_Vertical | JP12 |
| 1 | CLK Src | PinHeader_1x03_P2.54mm_Vertical | JP13 |
| 1 | SPKR OUT | PinHeader_1x02_P2.54mm_Vertical | JP14 |
| 1 | Phantom | PinHeader_1x02_P2.54mm_Vertical | JP15 |
| 1 | 2732_VCC | SolderJumper-2_P1.3mm_Open_RoundedPad1.0x1.5mm | JP401 |
| 1 | TestPoint | TestPoint_THTPad_1.0x1.0mm_Drill0.5mm | TP1 |
| 2 | 0.1u | C_Disc_D4.3mm_W1.9mm_P5.00mm | C1, C35 |
| 1 | 0.1 | C_Disc_D4.3mm_W1.9mm_P5.00mm | C2 |
| 30 | 0.1 uF | C_Disc_D4.3mm_W1.9mm_P5.00mm | C3, C4, C5, C6, C7, C9, C10, C11 +22 |
| 2 | 33u | CP_Radial_Tantal_D4.5mm_P2.50mm | C13, C36 |
| 3 | 47p | C_Disc_D4.3mm_W1.9mm_P5.00mm | C19, C30, C31 |
| 1 | 22uF | CP_Radial_D5.0mm_P2.00mm | C37 |
| 1 | 1.0kQ | R_Axial_DIN0204_L3.6mm_D1.6mm_P5.08mm_Horizontal | R1 |
| 3 | 0k | R_Axial_DIN0204_L3.6mm_D1.6mm_P5.08mm_Horizontal | R2, R3, R4 |
| 1 | 2.2kQ | R_Axial_DIN0204_L3.6mm_D1.6mm_P5.08mm_Horizontal | R5 |
| 1 | 5.6kQ | R_Axial_DIN0204_L3.6mm_D1.6mm_P5.08mm_Horizontal | R6 |
| 1 | 5.6kQ | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R9 |
| 1 | 22Q | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R10 |
| 1 | 100Q | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R11 |
| 4 | 4.7kQ | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R14, R15, R16, R17 |
| 1 | 56.0H | R_Axial_DIN0411_L9.9mm_D3.6mm_P12.70mm_Horizontal | R21 |
| 1 | 4.7kQ | R_Array_SIP8 | RN1 |
| 1 | 4.7kQ | R_Array_SIP9 | RN2 |
Lomax ColorMagic Redux design files
The KiCad project lives in the RichCini/LomasBoards repository on GitHub; these links point at the commit this page was built from.
Lomax ColorMagic Redux: common questions
How big is the Lomax ColorMagic Redux PCB?
The Lomax ColorMagic Redux measures 254 × 137.7 mm, has 4 copper layers and is 4.69 mm thick.
How many components are on the Lomax ColorMagic Redux?
148 components, from 72 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Lomax ColorMagic Redux design files?
From the RichCini/LomasBoards repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Lomax ColorMagic Redux design in my own project?
The repository has no license, so all rights stay with RichCini. Use it as a reference, and ask the author before reusing the design.
