Newsgroups: comp.sys.apple2 Path: news.uiowa.edu!chi-news.cic.net!newsfeed.internetmci.com!news.sprintlink.net!in1.uu.net!comp.vuw.ac.nz!actrix.gen.nz!dempson From: dempson@atlantis.actrix.gen.nz (David Empson) Subject: Re: IIe info wanted! Message-ID: Sender: news@actrix.gen.nz (News Administrator) Organization: Actrix - Internet Services Date: Sat, 21 Oct 1995 14:08:28 GMT References: <13329@gos.ukc.ac.uk> X-Nntp-Posting-Host: atlantis.actrix.gen.nz Lines: 352 In article <13329@gos.ukc.ac.uk>, Monts wrote: > > Can anyone tell me more about the IIe? It's history, specs etc? No-one else seems to be replying, so lets see what I can come up with. See below. > I gained acouple of these things over summer, but so far have > had no luck with booting either of them (BASIC works, but they > don't seem to want to talk to the disk drives). If you turn the IIe on or reboot using Ctrl-Apple-Reset, it should try to boot from the drive. Without a boot disk, you won't get very far. Pressing Ctrl-Reset at this point will put you into Applesoft BASIC, with no support for accessing the drive. You can load and save programs on tape, though. :-) To be able to use the disk drive from BASIC, you have to boot a system disk containing an operating system, either DOS 3.3 (the last version of the original Apple II operating system) or ProDOS (the current operating system). A ProDOS boot disk must also contain BASIC.SYSTEM to be able to access BASIC. An Apple II user group is probably your best source of either - most user groups have libraries of public domain software that is likely to include many bootable disks, and they should be able to supply you with a current ProDOS boot disk. > One of the machines is a genuine IIe, the other is a machine made > by Mitac, some Japanese characters on the keyboard. Seems like a > IIe inside though, with a disk, joystick, and TV interface built > in. The IIe has joystick and video interfaces built in, but the disk controller is a plug-in card (normally goes into slot number 6, counting from the left). Now, about the general history of the IIe: The IIe was originally released in 1983. It is an improvement on the design of the earlier Apple ][ and ][+. The main improvements are: - A full ASCII keyboard (the ][+ didn't have lowercase support and was missing several special characters). The keyboard also has "Open Apple" and "Solid Apple" keys, which are used by many IIe-specific programs for special commands (in conjunction with other keys). These keys correspond to the pushbuttons on a pair of paddles or a joystick. - 64K of RAM built in, instead of 4K to 48K. The ][/][+ can be brought up to 64K though the addition of a "language card" in slot 0. This provides 16K of RAM that is bank-switched into the memory area normally occupied by the ROM. The language card function is built into the IIe, and slot number zero is not physically present. - An auxiliary slot, for supporting IIe-specific memory cards, including some video cards. A 64K memory expansion card is supported, through bank switching. Most IIes have this card installed, giving them 128K memory. Many current IIe-specific programs require 128K. The extra memory is not directly supported by Applesoft BASIC. It can be used as a RAM disk by ProDOS, or directly by programs that need more memory. - Built-in hardware and firmware to support 80-column text display (a 1K or larger memory expansion card is required in the auxiliary slot) and "double high resolution" graphics (requires a 64K memory card in the auxiliary slot). Double hi-res graphics was not supported by the original IIe motherboard, but this was quickly replaced by a second revision. - Two character sets are supported ("primary" and "alternate"). The primary character set is the same as the ][+ (with the addition of the lowercase characters), while the alternate set removes support for flashing characters and replaces them with inverse lower case. - A self-test function is provided in the firmware. - General improvements to the hardware design to reduce the manufacturing costs and simplify the motherboard. An upgrade was released in 1985 (the "enhanced IIe"). An original IIe can be upgraded to an enhanced IIe by replacing four chips: the microprocessor (65C02 instead of 6502), the two firmware ROMs and the video ROM. The enhancement's main features are: - The 65C02 processor has several new instructions. Many current programs require an enhanced IIe because they use these instructions. The processor also consumes less power than the original 6502. - The firmware adds mini-assembler and search functions to the system monitor program, supports lower case command entry in BASIC and the monitor, has many improvements in the 80-column and diagnostic firmware, and has a much improved interrupt handler. - The video ROM has a set of "MouseText" characters, which include various symbols (e.g. open and solid Apple) and elements for implementing a windowed user interface on the text screen. There are some old programs that are not compatible with an enhanced IIe. The main reasons are the use of undocumented 6502 instructions, or reliance on undocumented entry points in the ROM. There are also several old programs that are affected by the MouseText characters (this is a cosmetic problem only, but it can make the program unusable becuase you cannot read its text output). In the original IIe video ROM, the alternate character set had two sets of inverse upper-case letters. The enhanced IIe replaces one of these sets with MouseText. The programs that were using the "wrong" set of characters will now display MouseText instead. If you aren't sure whether you have an original or enhanced IIe, look at the title which is displayed at the top of the screen when you boot the machine. An original IIe says "Apple ][", while an enhanced IIe says "Apple //e". A new version of the IIe was released in 1987. This has a redesigned motherboard and has a numeric keypad to the right of the keyboard. The firmware, video ROM and all other features are identical to the enhanced IIe. Different versions of the IIe were released in the USA and other countries. The international versions have a different motherboard layout (the auxiliary slot is in the middle of the motherboard in line with slot 3, instead of in the lower left corner) and support the standard video system and power frequency of the country of issue (e.g. the UK version is PAL/50 Hz) instead of NTSC/60 Hz. In addition, the international IIe has a different video ROM and keyboard layout, both of which are dependent on the country. The video ROM supports two character sets: the US set and the local set. A switch on the underside of the keyboard selects between them. The UK IIe is very similar to the US IIe in this area - the only difference is the shape and labelling of the keys, and a UK "pound" symbol on the '3' key in addition to the "hash" symbol. The "local" character set has a pound symbol in place of hash. These differences mean that a different enhancement kit is required for each country. For example, in the UK version, you need an enhanced UK video ROM. As far as I know, it is no longer possible to get hold of these ROMs - only the US version of the enhancement kit is still available. Alltech Electronics _might_ be able to supply the appropriate video ROM, but I doubt it. It is possible to enhance a IIe by replacing just the processor and firmware ROMs, leaving the original video ROM, but this will cause problems with programs that are expecting MouseText to be available. Given a local unenhanced version of the local video ROM and an enhanced version of the US video ROM, it is possible to copy the relevant parts from each ROM to create a local enhanced video ROM (you will need a 2764-type EPROM and an EPROM programmer that can handle the 2764 and 2732). I haven't worked out the details, but it wouldn't take me long to do so. General specifications not mentioned in the above: - The microprocessor runs at 1.023 MHz. - 15.75K of ROM. - Seven expansion slots along the back of the computer, which are fully compatible with the Apple ][ and ][+ (there are minor differences which affect some obscure cards). - The game I/O connector supports one to four paddles or one to two joysticks (four analog inputs, three digital inputs) plus four digital outputs and a general purpose "strobe" output are available on the internal 16-pin connector. - cassette tape input and output connectors. - internal speaker (square wave sound generation under direct software control). Video modes: - 40x24 or 80x24 text. Two pages are available, but the second one is almost never used and is not supported by the firmware. 80-column mode requires a RAM card in the auxiliary slot (providing at least 1K of RAM in the right place). - 40x40 lo-res graphics in 16 colours (with 4 lines of text, or 48 rows without text). There is also an undocumented 80x40 (or 48) "double lo-res" mode that is not supported by the firmware and is rarely used. Two pages are available, but the second one is almost never used. - hi-res graphics: 280x192 monochrome or 140x192 in six colours (with position restrictions). 4 lines of text may be provided, limiting the graphics area to 160 lines. Two graphics pages are available. - double hi-res graphics: 560x192 monochrome or 140x192 in 16 colours. Requires a 64K RAM card in the auxiliary slot. On the software side, you have Applesoft BASIC and the system monitor built into the ROM. You've already found BASIC. It was mostly written by Microsoft, and is similar to early implementations of Microsoft BASIC. It has Apple-specific extensions to support graphics, text output, slots and cassette tape. The system monitor is a general utility for doing machine-level stuff, such as moving, setting or examining memory and disassembling machine language programs. It is entered by typing CALL-151 from BASIC. To get back to BASIC, press Ctrl-C followed by RETURN. Warning: be very careful what you do while in the monitor. It can be fun to poke around and see what is in memory, but a little knowledge of the memory architecture of the IIe is vital to avoid serious problems (such as locking up the computer and having to reboot). If you use memory modification commands, you can easily overwrite areas of memory used by BASIC or the operating system, causing them to crash or misbehave at a later point. The monitor commands are very simple. Most of them take the form of a memory address (in hexadecimal) followed by a command letter. Some commands have more than one argument. The common commands, with examples of their use, are: start.end Dump a memory range e.g. 8000.807F dest