This is an emulator for the HP9816 desktop workstation that was based on an 8MHz Motorola 68000 processor. It was released in 1982 and was the first affordable computational workstation with three progamming environments: Basic, HPL and Pascal. This project is aimed at providing these excellent pre-mouse era programming environments on a modern linux machine for retrocomputing enthusiasts.
The code for the emulator was adapted from Olivier de Smet's 98x6 emulator for windows. See his HP98x6 website.
For history, documentation and software for the 9816 see the wonderful HP Comupter Museum
License: GPL V3
The UI graphics is implemented using Maorong Zou's EZWGL library which must be installed before building hp9816emu.
$ git clone https://github.com/dpenkler/hp9816emu.git hp9816emu
$ cd hp9816emu/src
$ make
$ cd <path to hp9816emu directory>
$ ./hp9816emu
Press the Run button
Load a disk image (e.g. Press on the 7908 Unit 0 label in the right hand panel and load the dmpas.hpi disk image)
The following HPIB peripherals are preconfigured on select code 7 and cannot be changed:
- 700: hp9121 amigo floppy disk drive units 0 and 1
- This is mainly for the HPL2 operating system.
- HPL2 boots from it but then hangs. (Workaround: boot HPL from ss/80 drive)
- Basic and Pascal OK.
- 701: printer - prints to file on host local file system: printer-xxx.txt
- 702: hp9122 ss/80 floppy disk drive units 0 and 1
- 703: hp7908/7911/7912 cs/80 hard drive unit 0
- 704: hp7908/7911/7912 cs/80 hard drive unit 0
When a Unit N label is clicked a menu to manage the corresponding disk image is posted.
When the emulator is Run initially it executes the boot rom which will search for an operating system to boot from the disks after a lengthy memory test. To associate a disk image with a drive click on the drive icon Unit N corresponding to the drive model you have an image for and load the appropriate disk image. Disk image files have the .hpi suffix and can be created using Ansgar Kuekes' hpdir utility. For example to create a disk image for a 7911 drive:
$# hpdir -initialize -lif -<drive-type> -n <lif-label> <image-file-name>
$ hpdir -initialize -lif -7911 -n 7911V1 7911V1.hpi
The HP Museum has lots of images in TD0 format. See Ansgar's Teledisk-to-hpi utilities to convert them to hpi format.
A sample disk image file for a 7908 drive is provided in the repo: dmpas.hpi You can load it by clicking on the 7908 Unit 0 button on the right hand panel. It contains a number of operating systems. By default it will boot into Pascal 1P SYSTEM_P. Note the dmpas.hpi disk image has been configured with 4 soft partitions. hpdir can only access the first partition.
To boot another OS press any key while the boot Rom is running the memory test. When you see "SEARCHING FOR A SYSTEM (ENTER To Pause)" type the two characters corresponding to the OS you want to boot:
1P for Pascal
2P for Pac-Man
1O for Othello
1H for HPL2
1Z for Basic
It is possible to save the current running system in a system image file.
If a system image file is passed as a runtime argument or loaded via the SystemImage menu the emulator loads and runs the image. Note: All files in use by the system when the image was created must still be present at the same location (hpi files).
The Settings button allows you to choose the memory size and whether
the floating point unit is enabled or not. These two settings only
take effect when initialising a New system image. Pascal programs
compiled with the $FLOAT_HDW ON$ directive require the floating
point unit to be enabled.
There are 5 general settings: "Default filename for system image", "Set system time", "Auto save system image", "Auto save on exit" and "Phosphor". The general settings take effect immediately.
The "Default filename for system image" is initially set to "system.img" and can be changed by entering another filename in the entry box. This filename is used when no filename is associated with the current system image when saving the system image:
- on Quit and "Auto save on exit" is enabled
- on New or Load and "Auto save system image" is enabled The current filename associated with the system image is reflected in the emulator window title.
"Set system time" when enabled will automatically set the system time for Pascal and Basic OS's
"Auto save system image" when enabled will automatically save the current image when loading a new image with Load or initialising a new image with New.
"Auto save on exit" when enabled will save the image on Quit. If no image file has been loaded the default filename for the system image is used.
Be careful not to uninitentionally overwrite the default system image file when enabling the "Auto save" options. No confirmation questions will be asked.
The "Phosphor" setting changes the colour of the screen. Colour choices are: "White", "Green" and "Amber".
To hide the Settings menu just click on the OK button.
The Speed button allows you to set the speed of the emulated MC68000 clock. Choices are 8, 16, 24, 32 MHz and Max. For games it should be set to the standard 8MHz frequency. The effective CPU frequency attained might slow down when interacting with the UI elements since the X-Window system locks out the CPU emulation thread during those times.
The speed setting takes effect immediately.
To hide the Speed menu without selecting a speed just click on the Speed button again.
This menu's items are as follows:
- New creates a clean system image and reboots the system. (Reflected by "New system imgage" in the window title).
- Load an existing image and run it.
- Save the running system in the existing image (Reflected in the window title).
- SaveAs the running system in a file of your choice. If ok will be reflected in the window title.
- Close saves the image in the existing (or default) file and dissociates the file name from the running image (Reflected by "Untitled" in the window title).
To hide the SystemImage menu without doing anything just click on the SystemImage button again.
The emulator is implemented using 2 threads. One for the main and UI functions and another to emulate the actual CPU. When the Run button is depressed (on) the CPU thread fetches and executes instructions and polls for I/O events. When the Run button is off the cpu thread goes into an idle loop.
The actual current CPU frequency and system memory size is shown in the panel. Note that CPU frequency is 0 when the emulator is not running.
This LED is on when the FPU is enabled in the current system image
When pressed the emulator terminates. If the autosave on exit flag setting is enabled the current system image is saved . If the current system image was loaded from an existing image file that image file is updated otherwise it is saved into the default system image file.
The right hand panel provides a number of buttons and indicators.
Each Unit N button posts a menu to manage the association of a disk image (.hpi file) with the corresponding drive. Entries will be greyed out if they are not applicable. These buttons can only be used when the emulator is running as they are handled by the cpu thread. The button label colour is black when no disk is associated with the unit otherwise it is red. When the volume label on the disk is read by the operating system the button label changes to the LIF Volume name.
- Load Posts a file selection widget to choose the file to associate with the drive
- Save Save the disk image back to the file from whence it came (floppies only)
- Eject Disassociates the disk image from the drive
- Cancel Hides the menu without doing anything
There is no RESET button on the keyboard. Click on the red button at the bottom of the right hand panel to reset the emulator. The system is reset immediately and any work in progress is lost and changed settings are not taken into account.
On the right hand panel there are 10 indicators
The indicators in front of the different drive address labels Addr:70X are lit when the corresponding drive is "connected" to the HPIB bus.
The indicators in front of the Unit N buttons flash when there is activity on the drive unit
The Unit N button labels change to the LIF Volume label and light red when there is a disk image associated with the drive unit.
The Leds above the red graphics reset button represent the CPU Status LEDs on the back of the 9816 CPU board.
The HP9816 special keys are mapped to the US QWERTY keyboard as follows:
UK Keyboard HP9816 Key
------------- ----------
[Escape] = Clear I/O
[Shft]+[Escape] = STOP
\ = Execute
| = Shift Execute
[Enter] = Enter
[Alt]+[Enter] = Execute
[Alt]+ ~ = Step
[Home] = Clear to end
[Alt]+[Home] = Recall
[Up] = Up
[Alt]+[Up] = Alpha
[Down] = Down
[Alt]+[Down] = Graphics
[Left] = Left
[Alt]+[Left] = Pause
[Right] = Right
[Alt]+[Right] = Continue
[Pg Up] = Shift up
[Alt]+[PG Up] = Result
[Pg Dn] = Shift down
[Alt]+[Pg Dn] = Edit
[Ins] = Insert char
[Alt]+[Ins] = Insert line
[Del] = Delete char
[Alt]+[Del] = Delte line
For HPL } = Right arrow symbol (assignment)
The mappings are defined in keyboard.c
The knob is emulated by the mouse wheel. Unshifted moves horizontally, shifted moves vertically.
Use the Issue feature in github to post requests for enhancements or bugfixes.