cards

Peripheral Cards

Disk ][ Controller

The Disk ][ Controller card emulates the floppy disk controller card and associated disk drives in the original Apple ][ systems. In the emulator, each card has two drives attached to it, referred to as drive 1 and drive 2. The floppy disks themselves are represented by a ``nibble'' image of the contents. The emulator emulates the hardware, but to be of any use, you will need to provide the firmware ROM code.

To use a disk card and drives, add these lines to your epple2.conf file, for example:

slot 6 disk
import slot 6 rom 0 /usr/lib/apple2/dos3x/16sector/controller/disk2.ex65

The first line uses the slot command to insert a disk contoller card into slot 6, which is the standard slot used for disk cards. The next line uses the import command to load the card’s ROM with the disk controller firmware. This firmware is known as the bootstrap'' or P5'' ROM code. It is seen by the Apple ][ at memory addresses $Cs00-$CsFF, where s is the slot number (so in the common case of the card being in slot 6, the ROM is at $C600-$C6FF). The firmware is copyright by Apple, and is available from the Apple II Library.

You can also load a floppy disk image (nibble format) into the drive,either by putting the load command into the epple2.conf file, or by using the command prompt in the emulator (F5 key). For example, you could load the DOS 3.3 system master into slot 6, drive 1, with this command

load slot 6 drive 1 /usr/lib/apple2/dos3x/16sector/disks/dos330/clean330sysmas.nib

Language

The language card emulates an Apple 16K RAM card, commonly called a Language Card. To use a language card, add this line to your epple2.conf file:

slot 0 language

Note that DOS and ProDOS will make use of a language card only if it is in slot zero.

The language card has RAM at addresses $E000 through $FFFF, as well as two banks of RAM at addresses $D000 through $DFFF. A program switches between these RAMs and/or the motherboard ROM by using the I/O switches at $C080 through $C08F.

The information area of the Epple ][ will show the current state of the language card as follows:

• R Read from card RAM (vs. motherboard ROM)

• W Write to card RAM (vs. write-disabled)

• B1 Use $D000 bank 1

• B2 Use $D000 bank 2

An overview of the I/O switches that control the language card is provided by Jim Sather in Understanding the Apple II, p. 5-30, Table 5.4, as follows:

BANK2	BANK1	ACTION
C080	C088	WRTCOUNT = 0*, WRITE DISABLE	READ ENABLE
C084	C08C
RC081	RC089	WRTCOUNT = WRTCOUNT + 1*	READ DISABLE
RC085	RC08D
WC081	WC089	WRTCOUNT = 0*	READ DISABLE
WC085	WC08D
C082	C08A	WRTCOUNT = 0*, WRITE DISABLE	READ DISABLE
C086	C08E
RC083	RC08B	WRTCOUNT = WRTCOUNT + 1*	READ ENABLE
RC087	RC08F
WC083	WC08B	WRTCOUNT = 0*	READ ENABLE
WC087	WC08F

^* Writing to expansion RAM is enabled when WRTCOUNT reaches 2.

Firmware

The firmware card emulates a (modified) Apple Firmware card. The firmware card is simply an alternate ROM, at addresses $D000 through $FFFF, that is switched using the I/O switches at addresses $C080 through $C08F. In order to make use of the firmware card, you will need to load the ROM with a binary image from a file on disk. For example, to insert an Integer BASIC firmware card into the emulator, add these lines to your epple2.conf file:

# Firmware card with Integer BASIC and old Monitor
slot 0 firmware
import slot 0 rombank 1000 /usr/lib/apple2/system/intbasic/intbasic.ex65
import slot 0 rombank 2425 /usr/lib/apple2/system/other/other.ex65
import slot 0 rombank 2800 /usr/lib/apple2/system/monitor/apple2/monitor.ex65

For an Applesoft BASIC firmware card, use these:

# Firmware card with Applesoft BASIC and Autostart Monitor
slot 0 firmware
import slot 0 rombank 0000 /usr/lib/apple2/system/applesoft/applesoft.ex65
import slot 0 rombank 2800 /usr/lib/apple2/system/monitor/apple2plus/monitor.ex65

Note that the addresses specified in the epple2.conf file for the rombank are based on the beginning of the bank ROM itself. For example, specifying 1000 (which is 1000 hex) represents the final memory address of $E000, because the bank ROM is always based at address $D000.

The idea is that you would load your motherboard with, for example, Applesoft BASIC and the Autostart Monitor ROM (to emulate an Apple ][ plus), and then install a firmware card with Integer BASIC and the old Monitor. Booting with DOS 3.3, then, would allow you to type FP to use Applesoft BASIC, or INT to switch to Integer BASIC.

Note that DOS and ProDOS will make use of a firmware card only if it is in slot zero.

Jim Sather, in Understanding the Apple II, on pages 6-18 through 6-21, explains how to modify a firmware card to allow independent switching of the $F800-$FFFF ROM memory. This area is occupied by the Monitor, so it is primarily intended to allow the user to switch between the old Monitor and the Autostart Monitor, independent of switching between Integer and Applesoft BASIC. The EPPLE ][ firmware card emulates this behavior.

The information area of the EPPLE ][ will show the current state of the firmware card as follows:

• D Read from firmware card $D000-$F7FF (vs. motherboard BASIC ROM)

• F8 Read from firmware card $F800-$FFFF (vs. motherboard Monitor ROM)

Clock

The clock card emulates a ProDOS-compatible real-time clock card for the Apple ][. To use a clock card, you will need to configure the EPPLE ][ to insert one into a slot, typically slot 4. You will also need to load the card with its ROM code, which is provided with the emulator in the clock.ex65 file. For example, add this to your epple2.conf file:

slot 4 clock
import slot 4 rom 0 /usr/lib/epple2/cards/clock.ex65

Of course you may need to adjust the path for your particular system.

To verify that the clock card is working correctly, you can run the following Applesoft program to retrieve the current time from the clock card and print it. This program assumes the card is in slot 4.

NEW

10 CALL -15360 : REM $C400 SLOT 4 ENTRY POINT
20 A = 512 : REM $0200 INPUT BUFFER
30 C = PEEK(A)
40 IF C < 160 THEN 99
50 PRINT CHR$(C);
60 A = A+1
70 GOTO 30
99 END

RUN

The card returns data (into the GETLN input buffer at $200) in the following format:

mm,ww,dd,hh,nn,ss,000,yyyy,Time Zone,v

• mm Month, 01-12

• ww Weekday, 00=Sunday…​ 06=Saturday

• dd Day, 01-31

• hh Hour, 00-23

• nn Minute, 00-59

• ss Second, 00-61

• 000 Milliseconds; always zero

• yyyy Year, e.g., 2008

• Time Zone time zone string (could contain lower-case characters, which won’t display correctly)

• v Daylight Saving Time in effect, 0=no, 1=yes

Note that only mm,ww,dd,hh,nn fields are used by ProDOS. The other fields, ss,000,yyyy,Time Zone,v, are an EPPLE ][ extension. Also note that ProDOS was not designed to work for years past 2007, so ProDOS will show the incorrect year, but the other fields will be accurate. I believe patches exist for ProDOS to fix this.

Standard Input

The ``standard input'' card doesn’t emulate a real piece of hardware; rather, it reads characters from standard input (stdin) (of the EPPLE ][ emulator).

To use a standard input card, add these lines to your epple2.conf file:

# IN#2 reads from standard input
slot 2 stdin
import slot 2 rom 0 /usr/lib/epple2/cards/stdin.ex65

That will insert a stdin card into slot 2, and then load its ROM image into the card. The stdin ROM is provided with the EPPLE ][ distribution.

For example, if you have a stdin card installed in slot 2, start the EPPLE ][ emulator from the command line, and at the Applesoft prompt, type IN#2. Then you can switch back to the command shell, and whatever you type will be fed into the emulated Apple. Use RESET or IN#0 to go back to normal.

Standard Output

The ``standard output'' card doesn’t emulate a real piece of hardware; rather, it acts similar to a printer card, but instead of sending characters to a printer, it sends them to standard output (stdout) (of the EPPLE ][ emulator).

To use a standard output card, add these lines to your epple2.conf file:

# PR#1 prints to standard output
slot 1 stdout
import slot 1 rom 0 /usr/lib/epple2/cards/stdout.ex65

This will insert a stdout card into slot 1 (which is the typical slot for a printer card), and then load its ROM image into the card. The stdout ROM is provided with the EPPLE ][ distribution.

For example, if you have a stdout card installed, at the Applesoft prompt, type PR#1. Whatever you type next will be echoed to standard output. Type PR#0 to stop echoing.