MGT SAM Coupe Core 

MGT SAM Couple Core for UnoXT Dev Board

Need CtrlModule repository for build https://github.com/emax73/ctrl-module

Core from ZXMicroJack: https://github.com/ZXMicroJack/sam-coupe

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MGT SAM Coupe
=============

Based on McLeod's SAM coupe core.  Added single disk drive reading from SDcard in either
FAT16 or FAT32 format in MGT format.  Also a PS2 mouse should be working - it works fine
on another board, but I don't have a splitter to test the ZXUNO yet.

Keys
----
- F12 - disk menu
- F5 - NMI button
- F1 - toggle joystick splitter setting
- CTRL-ALT-DEL - reset SAM
- CTRL-ALT-Backspace - reset to BIOS.
- SCROLL-LOCK - switch from VGA to RGB and back.
- (numeric keypad [-]) - switch on/off scanlines

Command after disk mounth: boot

Known issues
------------
- Only support for .MGT 80 track 10 sector, or CPM 80 track 9 sector format
- Border effects bad due to memory contention issues.

Links to sites with disk images
-------------------------------
- https://velesoft.speccy.cz/download.htm
- http://ftp.nvg.ntnu.no/pub/sam-coupe/

Disk image support
------------------
Many emulators running on host systems with infinite resources accept disk formats in ZIP format.  This core
does not.  Whereas it might be interesting to allow that support, it would be at the expense of other functionality
so for the sake of extracting and converting disk formats, for the moment, only MGT and CPM format is supported.

There is no support for copy protected disks with odd formats at present, so sorry, Lemmings is out unless there's a
cracked version.  This may change, the ZIP format probably will not.

To convert disks use Simon Owen's excellent SAMdisk utility available here: https://simonowen.com/samdisk/

2nd drive support
-----------------
SAMDOS stores the drive configuration along with the DOS on the disk and inherits the settings from the dos it loads.
Since not all SAMs had a 2nd drive, then if you boot a SAMDOS that was saved on a machine with only 1 drive, when you
try to DIR 2, then you will receive the message: "103 No such drive, 0:1".  To get around this, and to enable the
second drive after booting SAMDOS, you can enable the drive with the simple command:
- POKE DVAR 2, 208

If you resave the SAMDOS onto the disk, then it will save the setting and next time you boot that disk it will remember
that you had 2 drives configured.  This shouldn't affect PRODOS (CPM).

Feedback
--------
zx.micro.jack@gmail.com

ChangeLog
---------
release r1
  - Initial release

release r2
  - Joystick fix for all ZXUNOs
  - Brightness fix seen in POP wall textures
  - Blank first 40 sectors on create disk (effectively format properly - blank SAM disks are truly all zeros)
  
release r3
  - Support CPM 720kb disks
  - Updated SAA1099
  
release r4
  - 2nd drive
  - joystick splitter
  - activity LED