PAM/8 Operation

Operation Using a Mouse

You should find that PAM/8 works the same as a real H8 when you use a mouse to click the front-panel buttons on the GUI window. The buttons will even auto-repeat when you hold them down long enough.

But two-button sequences are not possible: there is no good way to hold down the '0' key while you press the '#' (return to montior) or '/' (reset) keys.

The solution was to use the Option key instead of the '0' button:

Return to Monitor (RTM)

Hold down the Macintosh Option key while you press the '#' button.

Reset

Hold down the Macintosh Option key while you press the '/' button.

While other two-key sequences were possible on the real H8, these are the only two-key sequences that PAM/8 supported and the only two that have been emulated.

Operation Using the Mac Keyboard

The emulator allows you to type commands on the Mac keyboard instead of pressing the front-panel buttons with the mouse. The H8 GUI window must be the front window in order for this to work.

Here are the equivalent keystrokes:

H8 Key	Macintosh Key(s)	H8 Key	Macintosh Key(s)
0	0	8	8
1	1, s	9	9
2	2, f	+	+
3	3, b	-	-
4	4, d, g	*	*
5	5, h	#	#
6	6, p	/	/, a
7	7, x	. (dot)	. (dot), r
RTM	option-#	Reset	option-/

So, for example, you can replace this front-panel button sequence:

    (reg) (pc) (alter) 0 3 0 0 0 0 (alter) (go)

....with:

    . 6 / 0 3 0 0 0 0 / 4

...or:

    r p a 0 3 0 0 0 0 a g

...typed on the Mac keyboard.

Return to Monitor (RTM)

Hold down the Macintosh Option key while you press the '#' keyboard key.

Reset

Hold down the Macintosh Option key while you press the '/' keyboard key.

When you type a valid PAM/8 key equivalent on the Mac keyboard, the key is "held down" for approximately 30 milliseconds. This is long enough that PAM/8 can see the keystroke on the keypad port and take action on it. It's short enough that you can type pretty quickly without problems. However, note that if you are doing heavy processing in a background application, keyboard emulation can get sluggish and not work well. This happens to the author whenever he prints. In these cases, it's best to use the keypad and mouse.

Tape Load and Dump

The Load and Dump keys work the same as they do in a real H8, except that they use disk files instead of tape casettes to hold a dumped memory image.

Use the "Open PAM Input Tape..." and "Open PAM Output Tape..." items on the File menu to open a file for input or output, respectively. Open the file before pressing the Load or Dump key. (Actually, you can press the key before opening the file; PAM/8 will simply wait for the "tape" device to become ready. If you change your mind, press Cancel.)

(You can also open a PAM/8 input tape by opening the tape file with the Finder. If an input tape file was already open, the file will be closed and the new one opened.)

As a reminder, to dump memory:

• open a Mac output file using "Open PAM Output Tape...";
• set (PC) to the program's entry point address;
• put the dump start address into cells 040.000A and 040.001A (low-order byte first!);
• display the memory address of the last byte of the program to be dumped;
• press the Dump key;
• close the Mac output file using "Close PAM Output Tape...".

Example: We have a program at 040.100A, with an entry point of 040.100A, that ends at 042.372A. Here are the key sequences required to dump this program:

(reg) (pc) (alter) 0 4 0 1 0 0 (alter)
(mem) 0 4 0 0 0 0
(alter) 1 0 0 0 4 0 (alter)
(mem) 0 4 2 3 7 2
(dump)

Remember to close the file.

To load the file later, simply open the file and press the Load key.