diff --git a/README.md b/README.md index c638c5c..f86421c 100644 --- a/README.md +++ b/README.md @@ -2,11 +2,12 @@ A Floppy Disk Interface card for the Sharp MZ series of machines (MZ-80B/MZ-80A/MZ-700/MZ-800/MZ-1500/MZ-2000/MZ-2200). This project is based on an iconic floppy disk interface card from the 1980's by the Aachen based company, Kersten & Partner GmbH. The company produced two cards, -the SFD-700 for the Sharp MZ-700 and the SFD-800 for the Sharp MZ-800. I initially reproduced the SFD-800 from the original schematic and board which I owned, the -design can be seen here: https://eaw.app/sfd800/. The SFD-800 was quite a flexible design and worked in the MZ-80B/MZ-800/MZ-1500/MZ-2000/MZ-2200 computer. Unfortunately -it didnt cater for the Sharp MZ-700 or indeed the Sharp MZ-80A. +the SFD-700 for the Sharp MZ-700 and the SFD-800 for the Sharp MZ-800. -I considered reproducing the SFD-700 exactly but it wouldnt work in an MZ-80A which uses a hardware trick to address the CPU speed shortcomings. I thus decided, based on the -SFD-800, to create a version 2 of the SFD-700 design which would work in all the Sharp MZ series computers. +Owning an original SFD-800, I reproduced the SFD-800 from the original schematic and the design can be seen here: https://eaw.app/sfd800/. This card has been well +tested and as the SFD-800 was quite a flexible design, it also worked in the MZ-80B/MZ-800/MZ-1500/MZ-2000/MZ-2200 computers. Unfortunately it didnt cater for the Sharp MZ-700 or indeed the Sharp MZ-80A. + +To address the requirement of a floppy interface for the Sharp MZ-700 and MZ-80A, I considered reproducing the SFD-700 exactly but analysis showed it wouldnt work in an MZ-80A which uses a hardware trick to +address the CPU speed shortcomings. I thus decided, based on the SFD-800 schematics, to create a version 2 of the SFD-700 design which would work in all the Sharp MZ series computers. Please see my website (in due course), https://eaw.app for more documentation and any recent updates.