
[ jos.dreesen greenmail.ch  2021 ]
 
A short overiew of the PCB's used in all Lilith generations :
================================================================

Basically there are only 2 Lilith versions :

- the first version with the Honeywell-Bull D120 cartridge drive and 128K x 16 mem.
  This has bootcode as part of the microcode, and is the machine I emulated in Emulith, my Lilith emulator.
  V1 has 5 82s191's worth of microcode.

- the second version has the 15MB IMI5018 MFM drive, on a WD1001-85 controller, and 256K x 16 memory.
  This one has a 2K boot-eprom, with mcode, on the IFU-board.
  V2 systems have 10 microcode roms.

========= the boards =================

--- ALU ---  
Basic ALU with 4x AMD2901, 16-word stack  & barrelshifter.

---- CDP ---
IO processor ( mouse, keyboard, serial channel ) 
The depicted board has been modified to add MAD18
A later version also added programmable baudrate option.

--- MCU ---
Microcode unit. Contains 2901 microcode and jumptable.
Lilith V1's have only the bottom set of 82s191 proms.
V2's have all 10 prom positions filled. 

--- IFU ---
Instruction fetch unit. 
Acesses memory 64 bit wide, and outputs 8 mcode words as required.
Used in  Lilith V1

--- IFU_X ---
as above, but with a 2716 boot eprom hotwired in, containing Mcode.
Used in Lilith V2's

--- IFU_2MB ---
as above, with proper space for the 2716.
Extended to give the Lilith 2MB memory space.

--- DSK	---
Diskcontroller for the Honeywell-Bull D120 Mididisk. Used in Lilith V1.

--- DSK_CTRL ---- 
contains an instance of the WD1001-85 MFM-disk controller.
Added is a RS232 channel dedicated to the FD6502 floppydisk processor.
Used in Lilith V2

--- Magnet ---
Optional 3MB Ethernet card
DIP swith sets the (8-bit !) Ethernet address

--- LPB	---
Optional driver for a LPB10 Laserprinter.

--- DSP ---
Display board for Lilith V1
The Dipswitches set the starting address of display ram.

--- NDSP ---
Display board for Lilith V2
	
--- MEM	--- Memory board (32Kx16). The same PCB layout was used in all Liliths.
V1 uses 4 boards filled with 4116's. 
Dipswitches sets high / low memory.
Only one MEM board should have U1 & U13 fitted.

V2 uses 2 boards filled with 4164 or 4256. An extra small PCB is mounted to provide the extra refresh signals needed.
Dipswitch is irrelevant.
Note that PCB rework is required to use V1 Ram boards in a V2 system.
A minimum of 2 boards is required, as both IFU and DSP read 64 bits in parallel.
Only one MEM board should have U1 & U13 fitted.
 	
--- motherboard ----
Not depicted, has dedicated slots, cards MUST be in the correct order.

--- DPU  ---
Optional debugging & monitoring board : an optional board containing a 6800 processor, controlled via a cassette-equipped HP terminal.
This can take over and control the complete Lilith. Used during debugging and for finding failures in production machines.
Not depicted, as I have never seen one.

