48K memory pcb

64K memory pcb. The blue rectangle is the switch bank to enable the pcb to work with the flashwriter video pcbs.  With the FW4 pcb you just set the switch but with the FW2 pcbs you had to set the switch and insert a jumper cable from the top of this memory card to the flashwriter 2 pcb.  I believe it was also possible to have a system with paged memory with a total of 8 x 64K giving 512K ram but this could only be used on a single user system.

8K memory pcb with switch bank at top right hand side of pcb to allow multiple cards to be used in a system to increase the total available memory.  Also visible on the right are the 4 voltage regulators.

FD-HD controller for the 5 or 10 Mbyte (Seagate) hard disks as well as the controller for the Tandon double sided double density hard sectored floppy drives.  Connection to the drives by the ribbon cables at the top of the pcb.  Could also be used as a floppy only controller. The 8 inch FD-HD controller for the 40 mb drives was very similar to this pcb.

Flashwriter 2 (FW2) pcb.  This handled the video out to the screen via the 5 pin connector at the top of the pcb on the left hand side. The parallel input from the keyboard was taken via a ribbon cable to the empty socket at the bottom right of the pcb.  Memory was 2K, hence the name FW2. The character generator prom is  located at the top right hand corner of the pcb.

Bitstreamer 2 pcb - The 3 empty sockets on the right of the pcb are for 3 plug-in cables that would route the RS232 connections from this pcb to the rear chassis.  The switch banks at the top left of the pcb (2 shown with 1 missing) set the baud rate from 110 to 9600.   The two blue plug sockets at the top centre of the pcb were connectors for the parallel ports, a paddle board would plug into these connectors and a ribbon cable would run to the parallel printer, usually a NEC 7700Q. This pcb generated  the “time slices” for each user in a multi-user system

Floppy drive controller for single sided single density Micropolis five and a quarter hard sectored floppy drive. The drives were connected by a ribbon cable from the connector at the top of the pcb.

Z80 cpu board Imhz  later upgraded to a 2 Mhz  processor.

ZCB.  This housed the  Z80 cpu running at 4Mhz and later at 6Mhz. It held the system and printer proms and had one serial RS232 port (empty socket at top right hand side of pcb) and the baud rate was set by the switch bank on the top left side of the pcb.  The blue connector at the top of the pcb was for the parallel printer. This pcb was common to the 3 and 5 range and was used to replace  a Z80 cpu board, Prom ram pcb and a Bitstreamer 1 pcb.

Flashwriter 4 (FW4) pcb.  An enhanced version of the FW2 pcb. Had 4K of memory and better character generation proms (2). Keyboard input (which is now serial) is through the set of pins beside the video out pins at the top left hand side of the pcb.

Prom/Ram pcb.  This held the system firmware in the early systems. System/boot prom and printer control prom. On very early systems I believe that this pcb could be fully populated by proms enabling the system to boot from this pcb and be a turnkey system. This pcb could also be used to “blow” proms under software control.  The switch and regulator at the top right hand side of the pcb supplied the extra voltage requirements for this operation.