Re: [retro-comp] Digest for retro-comp@googlegroups.com - 2 updates in 2 topics

[Sergey Kiselev]

Looks like I am very late to the party :)

My KiCad symbols, should contain most of the symbols you need:

https://github.com/skiselev/my_kicad_library

My simple Z80 RCBus Z80 CPU + Paged memory project. Implements Steve's idea of minimal Zeta SBC V2 compatible, from RomWBW perspective, memory pager: 

https://github.com/skiselev/z80-cpm

Enjoy!

On Fri, Jan 30, 2026, 20:36 <retro...@googlegroups.com> wrote:

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• Help with first Z80 design - 1 Update
• Z8000 modular computer - 1 Update

Help with first Z80 design

Enaiel <ena...@gmail.com>: Jan 30 07:27PM -0800 Thanks 7alken and Ed Silky for your help. I scoured through GitHub and cross-referenced datasheets to fix my symbols. I obsessively refined my design for a year due to tariffs. I'm think I'm finally ready to send it for production. I just have 20 ""Thermal relief connection to zone incomplete" errors to fix in KiCad before I send it. Any tips on how to fix these quickly?   Regards, -Enaiel   On Tuesday, January 27, 2026 at 9:18:40 PM UTC-5 7alken wrote:   hi Enaiel, try to peek there for Johs schematics and boards also ... we used all these; https://github.com/Z80-Retro/2063-Z80 https://github.com/Z80-Retro P.     On Monday, January 26, 2026 at 2:55:20 PM UTC+1 Enaiel wrote:   Hi all   I'm back to this project after a 1 year break due to tariffs. After reviewing my schematics, I realized that many of the KiCad symbols I downloaded from the internet have incorrectly numbered pins. Does anyone have a KiCad symbol library with one or more of the following ICs that they can share?   * Z80CPU * AS6C4008 * SST39SF040 * Z80SIO/O * DS1233   Additionally, a KiCad symbol for RCBus would be much appreciated.   Thanks, -Enaiel   On Sunday, February 23, 2025 at 12:07:22 PM UTC-5 Enaiel wrote:   Hi Wayne   > Yes, using the MM_SBC memory manager w/ MPCL_RAM and MPCL_ROM set to the same address would work fine for R---NNNN. That would allow you to bring up your board with the existing RomWBW codebase.   I was able to compile and build a ROM image with this configuration, Now to actually build the board and test it out.   > Ultimately, I would create a new memory manager for you that is more optimized by avoiding the second port I/O.   That would be really awesome!   Thanks, -Enaiel   On Monday, February 17, 2025 at 6:23:48 PM UTC-5 Wayne Warthen wrote:     Yes, using the MM_SBC memory manager w/ MPCL_RAM and MPCL_ROM set to the same address would work fine for R---NNNN. That would allow you to bring up your board with the existing RomWBW codebase.   Ultimately, I would create a new memory manager for you that is more optimized by avoiding the second port I/O.   Thanks, Wayne

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Z8000 modular computer

Tadeusz Pycio <ta...@wp.pl>: Jan 30 07:24AM -0800 The experience gained while working with the previous SBC computer led to the creation of the second version of the Z8002 SBC. The memory was expanded to 128 kB (64 kB system, 64 kB user) with full system mode access via 32 kB banks and the ability to switch ROM to RAM. The system clock does not need to be adjusted to the standard values required by the serial transmission circuit (it has its own clock). I decided not to use the Am8127 clock circuit with a built-in single-step function, and instead used the MAX708 supervisor. I am also in the process of designing a bridge module, Z-BUS to RCBus, which will allow me to access a large number of I/O modules for RCBus. The bridge will enable the use of vector interrupts for integrated circuits compatible with the Zilog specification. Once this work is complete, I will send the designs to production.   [image: Z8002MAX2.png]   [image: RCBus.jpg]

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[Sergey Kiselev]

And in many years I've been using KiCad I never seen that error... Perhaps you can share the zone settings, a screenshot showing the error marker, or you can upload the KiCad PCB file...

[Enaiel]

Hi Sergey

Thank you so much for the symbol library! I finally completed my design, but this library will definitely come useful.

Regarding the KiCad error, it's because I used Freerouter on a cramped board and so minimum number of spokes for a thermal relief is not met.