If I can add further to what Andrew has on the future boards… The V2 Z80 CPU board will be like the (very reliable) initial one except the is now has an option to use the top or bottom “half” of a 28C64 EEPROM (or UV-EPROM) by outputting a bit to a port. This effectively allows you to double the code capacity where your ROM resides (usually at F000-FFFF). The V2-SMB has some improvements also such as latching addresses and data lines – needed for high speed CPU’s when single stepping. It will now displays port as well as RAM values. A much more extensive ability to draw down DMA lines DMA0*-DMA3* (16 combinations) for master/slave use by outputting to a single port. The old inputting port ED for DMA0* activation is still retained for software compatibility. The V2-MSDOS support board now has a HT6542B IBM PC keyboard input chip allowing the connection of a standard PC keyboard to this board. There is also mouse input control. The Calendar/Clock chip has been changed to a DS12885 (again totally PC/MDSOS compatible) but utilizes a coin type battery backup. The DS12887’s are getting hard to fine. Since they have an internal battery that could be a problem a few years from now. The V2-80286 board has a modification that allows it in slave mode to itself call a further slave (i.e. two levels down). This would be of use with a HD controller or video board. John From: n8vem...@googlegroups.com [mailto:n8vem...@googlegroups.com] On Behalf Of lynchaj Hi! There are still several of the S-100 bus extender PCBs available. I think 6 or 7. John indicated the S-100 bus extender PCBs are working fine as is so which is good news. Still gathering pre-orders for the S-100 buffered prototyping boards. I would like to get that board order rolling soon so if you are not in the pre-order queue already please consider getting some S-100 buffered prototyping boards. They are useful that most builders will want several since it is much easier to just leave the prototype boards as they are than to try and reuse the buffered prototyping boards. They are intended to be "consumable" boards. Once the S-100 buffered prototyping boards are done then we can move on to some of the other respins in work. I have the S-100 SMB V2, S-100 Z80 CPU V2, S-100 PC AT V2 (aka MSDOS support board), and S-100 80286 CPU V2 all in work and optimizing right now. We can do some reorders of existing boards too once there is a enough pre-orders to warrant the manufacturing order. Please let me know. Thanks and have a nice day!
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