This is a DMA module for the Z80 CPU used in the RC2014.
**This version has still a bug**. One must connect the +5V signal (available at a pin on the PCB) to the RDY single pin. I tried only memor transfers at 7.8 MHz and they seem to work without problems. So the RDY-signal was floating and this means, that the DMA did NOT release the bus again (the test program was using the continous...
SIO/2 Board for RC2014 backplane
- 74ALS688 addr comparator for address decoding
- Block of 8 addresses assigned
- Arbitrary 8 address boundry
- SIO at Addr 0 does not conflict with IDE at address 10H (Aka Grant Searle design)
Z80 MiniTube is a Z80 secondary CPU card for BBC micro machines. It is a minimalist version of the Tube with it own Tube code. The Z80 version has up-to 512K RAM and can run any CP/M program version 2.X and 3.X.
BIOS, BDOS and CCP can be loaded from ROM or disks. It support the same disk systems that the BBC micro.
The graphic library GSX has been added for programs that support this.