Sharp MZ Series
+Personal and Business Computer Emulation
Written by Philip
+Smart, 2018 for the Terasic DE10 Nano board under the
+MiSTer framework.
This project aims to
+provide full emulation (along with extensions) of the Sharp MZ Series
+Computers.
The following
+emulations have been
+written: ..and the following are under development:
- +MZ80K + - +MZ800
+ +- +MZ80C + - +MZ80B
+ +-
+MZ1200
+ -
+MZ2000
- MZ80A
- MZ700
The current emulations provide:-
+ +· +48K RAM for +MZ80K,C,1200,A
+ +·
+64K RAM for
+MZ700
·
+Hardware
+Tape Read/Write with selectable 1x - 32x Fast Mode
·
+Turbo Mode
+1x - 32x (ie. 112MHz for MZ700)
·
+Programmable
+Character Generator (PCG-8000/PCG-1200)
·
+40x25,
+80x25 Mono and Colour Display Modes
·
+320x200,
+640x200 8 Colour Bit addressed Graphics
·
+Updateable
+Monitor Rom, CGRom, Keymap, User Rom, FDC Rom per
+Emulation type.
·
+i8253 mono
+audio
Enhancements in
+test/under development:
·
+Floppy Disk
+Drive/Controller 5.25"
·
+Quick Disk
+Controller
· +Dual +digital Joystick Input (MZ700)
+ +Known Issues
·
+Tape Write
+isn’t working correctly, I made some structural changes resulting in it no
+longer working, so this needs to be resolved.
·
+Keyboard
+mappings could be better, especially for the MZ1200 which is the Japanese
+version of the MZ80A.
·
+HDMI needs
+to be re-enabled in the design.
·
+The Aspect
+Ratio/Scandoubler options aren’t working on the VGA
+output.
Installation
1. +Follow the Setup Guide to +create a new SD boot disk. https://github.com/MiSTer-devel/Main_MiSTer/wiki/Setup-Guide
+ +2. +Copy across to the SD (via scp or mount the SD under Windows/Linux and use local copy +commands) the latest RBF file from the releases folder, ie:-
+ +scp SharpMZ_MiSTer/releases/SharpMZ_<data>.rbf +root@<de10 ip address>/media/fat/SharpMZ.rbf # +Target name can be anything you like ending with .rbf
+ +3. +Make a SharpMZ +directory on the SD card, ie:
+ +ssh root@<de10 ip +address>
+ +mkdir /media/fat/SharpMZ
+ +4. +Copy any Rom Files, MZF Tape +Files, DSK files across to the new directory, ie:
+ +scp *.mzf +root@<de10 ip address>:/media/fat/SharpMZ/
+ +5. +Start the MiSTer +menu (ie. press the DE10 reset button if it is not +showing).
+ +6. +Select the SharpMZ +core (or whatever name you called it).
+ +7. +The emulator will boot into an +MZ80K model with the SP-1002 monitor.
+ +8. +Press F12 to change the +configuration, select Save Config to store it.
+ +Design Summary
The idea of this design +is to keep the emulation as independent of the HPS as possible (so it works +standalone), only needing the HPS to set control registers,
+ +read/write tape/floppy
+cache ram with complete images and overlay the menu control system. The MiSTer/HPS system is an excellent base on which to host
+emulations, but there may be someone wanting to port this emulator to another
+target such as the Xilinx Zynq 7000 (which I have also been playing with). This
+in theory should allow easier porting if someone wants to port this emulator to
+another platform and control it with a PC (parallel port), HPS or instantiate
+another CPU as the menu control system.
As the Cyclone V SE on
+the Terasic DE10 has 5.5Mbits of memory, nearly all
+the RAM used by the emulation is on the FPGA. The Floppy Disk Controller may
+use HPS memory/external SDRAM depending on whether I decide to cache entire
+Floppy Disks as per the CMT unit or use the secondary SD card.
Menu
+System
The MiSTer menu +system is used extensively on this design as the Front End +control. It allows for loading/saving of cassettes and floppy disks, setting +the machine parameters, the display parameters, debugging and access to the MiSTer control menu.
+ +Tape Storage
In order to use +the emulation seriously, you need to be able to load and save existing +programs. Initially this was via a CMT (tape) unit and later moved on to +Floppy/Quick Disks.
+ +This menu +controls the hardware CMT unit and has the following choices:
+ +· +Load direct to RAM
+ +This option +allows you to load an MZF format tape file (ie. 128 +bytes header + code) directly into RAM. It uses the Load Address and Size +stored in the header in order to correctly locate the code and also stores the +header in the Cassette Work area at 10F0H. After load is completed and warm +reset is made. The details of the tape are displayed on-screen and in order to +run the program, simply issue the correct monitor command, ie. +J1200 (Jump to 1200H).
+ +· +Queue Tape
+ +A real cassette +has 1 or more programs stored on it sequentially. The emulation cache only +stores 1 full program so this is a mechanism to line up multiple programs and +they will be fed into the emulation cache as it becomes empty, thus simulating +a real cassette.
+ +Selecting this +option presents you with a directory listing of all MZF files. Choose one per +selection and it will be added to the Queue. The programs queued will be +displayed on the menu.
+ +· +Clear Queue
+ +This option +allows you to purge all queue entries.
+ +· +Save Tape
+ +This option +allows you to save a program to the MiSTer SD card +which is in the emulation cache. Normally the emulation would have written a +program/data to tape (ie. via the BASIC ‘SAVE’ +command) which in reality is stored in the emulation cache.
+ +The tape is +saved under the name given in the emulation save command (ie. +in BASIC ‘SAVE “myfile”’ would result in a file +called myfile.mzf being saved).
+ +· +Auto Save Tape
+ +This option +allows you to auto save the emulation cache. Ie. when +an emulation save completes, a flag is raised which is seen by the MiSTer program and the emulation cache is saved to SD under +the name given in the emulation.
+ +· +Tape Buttons
+ +This option +allows you to set the active Tape buttons, ie. Play, +Record or Auto. Auto is a hardware mechanism to detect if the emulation is +reading or writing to tape and process accordingly.
+ +· +Fast Tape Load
+ +This option +allows you to set the speed of the tape drive. On the original machines, the +tape runs at 1200baud which is quite slow, so use of this option is +recommended.
+ +You can select +one of: "Off", "2x", "4x", "8x", +"16x", "32x"
+ +Selecting “Off” +runs the tape drive at the original speed.
+ +Machine
The emulation +emulates several Sharp MZ computers and this menu allows you to make selections +accordingly.
+ +· +Machine Mode
+ +This option +allows you to choose which Sharp MZ computer is emulated. Currently the choices +are:
+ +"MZ80K", +"MZ80C", "MZ1200", "MZ80A", "MZ700" +with "MZ800", "MZ80B", "MZ2000" in the pipeline.
+ +· +CPU Speed
+ +This option +allows you to set the speed at which the emulation runs. Generally speaking, +higher speeds can be beneficial in non-graphics based +applications although some games benefit from a small speed boost. The choices +are:
+ +MZ80K/C/1200/A => "2MHz", "4MHz", "8MHz", "16MHz", "32MHz", +"64MHz"
+ +MZ700 => "3.5MHz", +"7MHz", "14MHz", "28MHz", "56MHz", +"112MHz"
+ +· +Audio Source
+ +This option +allows you to choose what is played through the audio output. The choices are:
+ +"Sound" => The mono audio generated by the +emulation output on L/R channels.
+ +"Tape" => The CMT signals, Playback on Right +channel, Record on Left channel. In theory you should be able to connect the +right channel to an external tape drive and record to physical tape.
+ +· +Audio Volume
+ +This option +allows you to set the output volume. There are 16 possible steps from Min .. Max.
+ +· +Audio Mute
+ +This option +allows you to Mute the output.
+ +· +Rom Management
+ +The emulation +comes with the Monitor, Character Generator and Key Mapping Roms +built-in for each machine emulated. This option selects a sub-menu which allows +you to upload non-standard Roms when the emulation is +started (ie. the Core is selected).
+ +o +Machine Model
+ +This option +allows you to select the emulated Sharp MZ computer to which the custom rom +images will affect. The choices are:
+ +"MZ80K", +"MZ80C", "MZ1200", "MZ80A", "MZ700" +with "MZ800", "MZ80B", "MZ2000" in the pipeline.
+ +o +User ROM
+ +On some machine +models (ie. MZ80A) there exists a socket to place a +User ROM, which will have control passed to it should the first byte be 0 and +non-writeable. Although this option only exists on certain models, it is a nice +to have feature it is available for all machine models.
+ +This option +allows you to enable or disable the User ROM (NB. If you enable this option, it +only enables hardware select, you still need to upload a ROM which has the +first byte set to 0).
+ +o +Floppy Disk ROM
+ +A Floppy Disk +drive was an expansion option for the Sharp MZ computers, and with the advent +of the MZ700, a Quick Disk drive was also an option. These options typically +held control software in a ROM at location F000H. This option allows you to +enable this feature, albeit you still need to upload a ROM.
+ +o +Enable Custom Rom
+ +This section +allows you to enable custom Roms and select the image +which will be uploaded. For each Rom, you can enable or disable. If enabled, +you can choose the required file. The Roms which can +be customized are:
+ +§ +Monitor (40x25)
+ +§ +Monitor (80x25)
+ +§ +Char Generator
+ +§ +Key Mapping
+ +§ +User Rom
+ +§ +Floppy Disk
+ +The Monitor Rom +is a special case. Most of the Personal Sharp MZ Computers were only able to +display 40x25 characters so the Rom hardcodes these parameters. Some people +required wider screens for use with CPM, so hardware modifications were made to +create an 80x25 display. The emulation is capable of both modes but in order to +run correctly, a different Monitor Rom for 80x25 display is needed.
+ +Display
The display on +the Sharp MZ computers was originally quite simplistic. In order to cater for +enhancements made in each model and by external vendors, the emulation has +several configurable parameters which are grouped under this menu.
+ +· +Display Type
+ +This option +allows you to select the display used. Normally, when a machine model is +chosen, it defaults to the original display, this option allows you to override +the default. The choices are:
+ +"Mono +40x25", "Mono 80x25 ", "Colour +40x25", "Colour 80x25"
+ +· +Video
+ +An extension to +the original design was the addition of a graphics frame buffer. It is possible +to blend the original display video with the graphics frame buffer. This option +allows you to enable or disable the original display video (ie. +if you only want graphics).
+ +· +Graphics
+ +There were +various add-on boards made available in order to display bit addressable pixel +graphics. This is my extension to the original design and as I gather +information on other add-on boards, I will adapt the hardware interface so it +accommodates these options. Please see the section below on the graphics frame +buffer details if needed. This option allows you to enable or disable the +display of the graphics frame buffer (which is blended with the original character based video output).
+ +· +VRAM CPU Wait
+ +I deviated from +the original design by adding a pixel based display +buffer. During the Vertical Blanking period, I expand the character +based VRAM and Attribute RAM into pixels and store them in the display +buffer (a double buffer technique). This consequently means that no snow/tearing +will occur if the CPU accesses the VRAM/Attribute RAM during the visible +display period. The original design added software waits (MZ80K) and hardware +CPU wait states (MZ80A/700) to eliminate snow/tearing and due to the addition +of double buffering, this is no longer needed. You can thus disable the wait +states with this option and gain some speed or enable them to keep +compatibility.
+ +· +PCG Mode
+ +All of the Sharp +MZ computers used character generators which were hard coded in a ROM. External vendors offered add-ons to allow for a +Programmable Character Generator based in RAM. This option enables the +Programmable Character Generator which is compatible with the HAL PCG-8000/PCG-1200 add-ons.
+ +· +Aspect Ratio
+ +This option is a +MiSTer framework extension which converts the Aspect +Ratio from 4:3 to 16:9. It doesn’t work at the moment with VGA output but +should work on HDMI. Use this option to choose the desired format.
+ +· +Scandoubler
+ +This option is a +MiSTer framework extension which doubles the scan +lines to widen/improve the image of older computer displays. It doesn’t work +correctly with VGA output at the moment but should work on HDMI. The choices +are: "None", "HQ2x", "CRT 25%", "CRT +50%", "CRT 75%"
+ +System
This is the MiSTer main control menu which allows you to select a core, +map keys etc.
+ +Debugging
As you cannot +easily get out a trusty Oscilloscope or write breakpoint/debug messages with an +FPGA, I’ve added a debugging mode which can be used at any time without +affecting the emulation (unless you choose a debug frequency in which case the +emulation will run at the selected frequency).
+ +Basically, the 8 +LED’s on the main DE10 main board can display a selectable set of signals, +either in auto mode (move from set to set after a fixed period) or a static +set. The sample rate of the signals displayed on the LED’s is selectable from +the Z80 CPU frequency down to 1Hz. You can also attach an oscilloscope onto the +LED’s and thus see the waveform if a simple flicker is not sufficient. In +addition, you can slow the CPU frequency down in steps from 1MHz to 1/10Hz so +you have a good chance of seeing what is happening internally.
+ +This debugging +addition is also a great method of understanding the internals of a computer +and seeing the Z80 in action.
+ +To use the debug +mode, press F12 to enter the MiSTer menu, then select +Debug and you are offered the following choices:
+ +· +Select Memory Bank
+ +This option +allows you to select one of the memory banks so it can be written to a local +(DE10 SD Card) file.
+ +"SysROM" = System ROM. This is +the complete concatenated set of Monitor ROM’s for all the emulations.
+ +"SysRAM" = System RAM. This is +the 64K Main RAM.
+ +"KeyMap" = Key Mapping ROM. +This is the complete concatenated set of Key Mapping’s for all the emulations.
+ +"VRAM" + = Video RAM. This is the 2K Video RAM concatenated with +the 2K Attribute RAM.
+ +"CMTHDR" += Cassette Header. This is the 128 byte memory holding +the last loaded or saved tape header.
+ +"CMTDATA" = Cassette Data. This is the 64K memory holding +the last loaded or saved tape data.
+ +"CGROM" += Character Generator ROM. This is the complete concatenated set of CGROM’s for +all the emulations.
+ +"CGRAM" += Character Generator RAM. This is the 2K contents of the Programmable +Character Generator RAM.
+ +"All" += This is the complete memory set as one file.
+ +· +Dump To <memory bank +name>
+ +Dump the +selected memory bank. The system will show the file name used for the dump.
+ +· +Debug Mode
+ +Select to Enable +or Disable
+ +o +CPU Frequency
+ +Select the CPU +Frequency which can be one of:
+ +"CPU/CMT", +"1MHz", "100KHz", "10KHz", "5KHz", +"1KHz", "500Hz", "100Hz", "50Hz", +"10Hz", "5Hz", "2Hz", "1Hz", +"0.5Hz", "0.2Hz", "0.1Hz"
+ +o +Debug LEDS
+ +Select to +Enable or Disable
+ +§ +Sample Freq
+ +This is the +sampling frequency used to sample the displayed signals. It can be one of:
+ +"CPU/CMT", +"1MHz", "100KHz", "10KHz", "5KHz", "1KHz", +"500Hz", "100Hz", "50Hz", "10Hz", +"5Hz", "2Hz", "1Hz", "0.5Hz", +"0.2Hz", "0.1Hz"
+ +§ +Signal Block
+ +This is the +signal block for display. It can be one of:
+ +"T80" => CPU Address/Data Bus +and associated signals.
+ +"I/O" => Video, Keyboard and Select signals.
+ +"IOCTL" => External I/O Control. +Address/Data and Select signals.
+ +"Config" => Register configuration +signals.
+ +"MZ80C +I" => 5 sets of signals +relating to the MZ80K/C/1200/A/700/800.
+ +"MZ80C +II" => An additional 5 +sets of signals.
+ +”MZ80B I" => 5 sets of signals relating to +the MZ80B/MZ2000.
+ +"MZ80B +II" => An additional 5 +sets of signals.
+ +§ +Bank
+ +This is the +Bank within the Block to be displayed on the LED’s. It can be one of:
+ +"T80"
+ => "Auto", "A7-0",
+"A15-8",
+"DI", "Signals"
"I/O" + => "Auto", "Video", +"PS2Key", "Signals"
+ +"IOCTL” +=> "Auto", "A23-16", +"A15-8", "A7-0", +"Signals"
+ +"Config" + => "Auto", "Config +1", "Config 2", "Config 3", "Config 4", +"Config 5"
+ +"MZ80C +I" => "Auto", "CS +1", "CS 2", +"CS 3", "INT/RE", +"Clk"
+ +"MZ80C +II" => "Auto", + "CMT 1", "CMT +2", "CMT 3"
+ +"MZ80B +I" => Not yet defined.
+ +"MZ80B +II" => Not yet defined.
+ +Graphics
+Frame Buffer
An addition to the original design is a +640x200/320x200 8 colour Graphics frame buffer. There +were many additions to the Sharp MZ series to allow graphics (ie. MZ80B comes with standard mono graphics) display and as +I don’t have detailed information of these to date, I designed my own extension +with the intention of adding hardware abstraction layers at a later date to add +compatibility to external vendor add-ons.
+ +This frame buffer is made up of 3x16K RAM +blocks, 1 per colour with a resolution of 640x200 +which matches the output display buffer bit for bit. If the display is working +at 40x25 characters then the resolution is 320x200, otherwise for 80x25 it is +640x200.
+ +The RAM for the Graphics frame buffer can +be switched into the main CPU address range C000H – FFFFH by programmable +registers, 1 bank at a time (ie. Red, Green, Blue +banks). This allows for direct CPU addressable pixels to be read and/or written. +Each pixel is stored in groups of 8 (1 byte in RAM) scanning from right to left +per byte, left to right per row, top to bottom. Ie. +if the Red bank is mapped into CPU address space, the byte at C000H represents +pixels 7 - 0 of 320/640 (X) at pixel 0 of 200 (Y). Thus 01H written to C000H +would set Pixel 7 (X) on Row 0 (Y). This applies for Green and Blue banks when +mapped into CPU address space.
+ +In order to speed up display, there is a Colour Write register, so that a write to the graphics RAM +will update all 3 banks at the same time.
+ +The programmable registers are as follows:
+ +Graphics Bank Switch Set Register: I/O +Address: E8H (232 decimal)
+ +Switches in 1 of +the 16Kb Graphics RAM pages (of the 3 pages) to C000 - FFFF. The bank which is +switched in is set in the Control Register by bits 1/0 for Read operations and +3/2 for Write operations. This bank switch overrides all MZ80A/MZ700 page +switching functions.
+ +Graphics Bank Switch Reset Register: I/O +Address: E9H (233 decimal)
+ +Switches out the +Graphics RAM and returns to previous state.
+ +Control Register: I/O Address: EAH (234 +decimal)
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+ Read mode (00=Red Bank, 01=Green Bank, + 10=Blue Bank, 11=Not used). +Select which bank to be read when enabled + in CPU address space. + |
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+ Blend Operator (00=OR ,01=AND, 10=NAND, + 11=XOR). +Operator to blend Character display with + Graphics Display. + |
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Red Colour Writer +Register: I/O Address: EBH (235 decimal)
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Green Colour +Writer Register: I/O Address: ECH (236 decimal)
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Blue Colour +Writer Register: I/O Address: EDH (237 decimal)
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+ Pixel 0 Set to Blue during indirect + write. + |
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For Indirect mode (Control Register bits +3/2 set to 11), a write to the Graphics RAM when mapped into CPU address space +C000H – FFFFH will see the byte masked by the Red Colour +Writer Register and written to the Red Bank with the same operation for Green and +Blue. This allows rapid setting of a colour across +the 3 banks.
+ +Credits
My original intention was to port the MZ80C +Emulator written by Nibbles Lab https://github.com/NibblesLab/mz80c_de0 +to the Terasic DE10 Nano. After spending some time +analyzing it and trying to remove the NIOSII dependency, I discovered the MISTer project, at that point I decided upon writing my own +emulation. Consequently some ideas in this code will +have originated from Nibbles Lab and the i8253/Keymatrix +modules were adapted to work in this implementation. Thus +due credit to Nibbles Lab and his excellent work.
+ +Also credit to Sorgelig +for his hard work in creating the MiSTer framework +and design of some excellent hardware add-ons. The MiSTer +framework makes it significantly easier to design/port emulations.
+ +Links
The Sharp MZ Series Computers were not as +wide spread as Commodore, Atari or Sinclair but they had a dedicated following. +Given their open design it was very easy to modify and extend applications such +as the BASIC interpreters and likewise easy to add hardware extension. As such, +a look round the web finds some very comprehensive User Groups with invaluable +resources. If you need manuals, programs, information then please look (for +starters) at the following sites:-
+ + + +https://www.sharpmz.no/
+ + + +http://www.sharpusersclub.org/
+ +http://www.scav.cz/uvod.htm (use chrome to auto translate Czech)
+ +