Pico/Elf V2 is an evolution of the Micro/Elf. Pico/Elf removes the address display, data displays, and input togges along with associated circutiry in order to add an RS232 port, ROM socket and IDE/CF interface, allowing for a complete machine capable of running Elf/OS.

Features:

• 32k Ram
• 32k Rom
• RS232 port
• IDE/CF port
• Compact design, board is only 5" x 3.75"
• Micro/Elf Expansion connector

News:

11/17/2020	Added pinout of expansion connector Added Bernie Murphy's really nice memory map of the Disk-less ROM
10/03/2020	Updated BOM and posted picture of parts layout
9/29/2020	The Pico/Elf V2 boards have been ordered
9/28/2020	Added a download for the Pico/Elf V2 BIOS image. This image contains the Elf/OS installer and the Pico/Elf V2 bios. You can download it here
8/8/2020	Assembled one of the production prototypes (pictures below). Now I just need to find what I need to run it.
8/4/2020	Wow that was quick! The test run of 5 boards arrived today. I posted a photo below. Will try to get one built and tested in the next couple days.
8/3/2020	I received an email this morning indicating the production prototypes are complete and have been shipped. I ordered 5 of these prototypes, I will build 1, leave one unbuilt and for the remaining 3 I would like to see if anybody would like to help testing of the boards. If you are interested in being one of the testers let me know. All I ask is that you have the requisite knowledge, skills, and tools needed to help debug the board should it be needed. As a thank you for helping test the boards, I will provide the boards at no cost.
8/2/2020	Official start of this project. At this time 5 test boards have been ordered to check the quality of the new PCB fab that I am using for this project. At this time 33 people have requested a total of 50 boards. Thanks to the feedback from the COSMAC group in providing me a more affordable PCB fab, I am also considering ordering a new block of Micro/Elf boards for those who may be interested in them as well. Thanks to the more affordable PCB fab, exptected price per board is $1.25 plus shipping from me to you. Plese note this price is an estimate and may change when the bulk order is placed.

Preliminary Parts List

Please note this parts list is preliminary and may change as I find better options for some parts. These parts are sourced from Digi-key and Jameco.

For those who prefer to use 74HC parts:

IC1	74hc373	296-1591-5-ND	0.53	0.53
IC3	74hc04	296-1566-5-ND	0.57	0.57
IC4	74hc138	296-1575-5-ND	0.44	0.44
IC5	74hc32	296-1589-5-ND	0.39	0.39
IC6	74hc00	296-1563-5-ND	0.39	0.39
IC8	74hc75	296-9240-5-ND	0.89	0.89
IC9	74hc32	296-1589-5-ND	0.39	0.39
IC10	74hc00	296-1563-5-ND	0.39	0.39
IC11	74hc74	296-1602-5-ND	0.39	0.39
IC12	74hc86	296-8375-5-ND	0.44	0.44

Expansion Connector:

       A0  1   2  D0
       A1  3   4  D1
       A2  5   6  D2
       A3  7   8  D3
       A4  9  10  D4
       A5 11  12  D5
       A6 13  14  D6
       A7 15  16  D7
      TPA 17  18  TPB
     /INP 19  20  EF1
     /OUT 21  22  EF2
    PORT1 23  24  EF3
  /DMA_IN 25  26  EF4
 /DMA_OUT 27  28  INT
     /MRD 29  30  /MWR
      SC0 31  32  SC1
        Q 33  34  GND
    PORT2 35  36  PORT5
    PORT3 37  38  PORT6
    PORT4 39  40  PORT7

Gallery:

Pico/Elf V1 prototype	Unbuilt V2 prototype pcb	Pico/Elf V2 prototype	Pico/Elf V2 production prototype
Assembled Pico/Elf V2	Populated Pico/Elf V2	Parts Layout

Here is a really nice memory map produced by Bernie Murphy of the Disk-less ROM: