Here is a new version of the Express Modem FAQ. The only major changes are in brief: 1) Unofficial confirmation that there was infact a major bug fix in version 1.1.2 of the Express Modem CDEV. Older versions apparently polled the CPU unnecessarily even when the modem was inactive (but not turned off). 2) New version of the PowerBook CDEV changes the labeling of the 'internal' and 'external' modem buttons to 'compatible' and 'normal' respectively. The Macintosh Express Modem (FAQ) v.1.1 1.1 Introduction Ever since the Express Modem (EM) came out there has been a lot of traffic on the net surrounding the EM. This document is a consolidation of information that hopefully will answer the most common question that Express Modem owners, or those considering buy one, might have that are not well covered elsewhere. It is not intended to replace the manual that comes with the modem, but it does clarify some issues that are poorly covered in the manual. It does not attempt to answer any questions you migh have about the Apple Fax program, or how to make successful connections, but provides some basic, but essential, information all EM users should be aware of before they try to tackle more difficult problems. It is mostly directed a PowerBook users for the simple reason that don’t know enough about its use on the AV Macs. Most of this is based on personal experience so if you have any coments, corrections, questions, or hints you want to share don’t hesitate to contact me. Espen H. Koht email@example.com 2 General 2.1 What is the Macintosh Express Modem? The Macintosh Express Modem is actually several things. Unlike most modems the EM is not just a piece of hardware--it is also the Express Modem software and this is essential to the operation of the modem. The key to the EM is that many of the things usually done with special hardware is done in software by the Macintosh itself. For example, error correction and compression is done in software rather than hardware. There are currently several different Express Modems. Two of the modems are intended for use in Powebooks. One model is for the PB 160 and 180 series, and another for the Duo series. The main difference is the size of the internal board. There is also an EM for the AV series of desktop Macintoshes. Rather than a board that goes into the mac, the AV Express Modem is mainly the software. The hardware is the built-in DSP chip in the AV and an adaptor that attachs to the AV’s GeoPort. 2.2 Can I use the same software with all Express Modems? Unlike the hardware the Express Modem software is common to all the Express Modems. It might work slighly differently depending on what machine you are using it on, and the AV macs do require some extra bits of software, but the Express Modem control panel which is the ‘heart and soul’ of the EM is the same as on the Powerbooks. Just make sure you have the right version of the sofware. ie. both the 880AV and the Duo 230 will work with version 1.1.2 of the Express Modem software. 2.3 What version of the software do I need to install? The most important part of the software package is the Express Modem control panel (CDEV). This is the heart and soul of the EM--without this your modem will not work! There have been some (essential!) software revisions of the Express Modem Control Panel: 1.0 Avoid this! This first version was so buggy that for most people the modem didn’t work at all with this software! 1.0.1 Fixed enough bugs to make the modem actually work. 1.0.4 Fixed several more bugs and quirks and improved performance significantly. You should not be using anything older than this version! 1.1.2 New version that works with the AVs (if you have an AV you can’t use any older versions). According to Apple the only other fix in this version is improved performance with non-CTB aware programs. This might not be the whole story. As far as I can tell from informal testing and have had confirmed by unoffcial sources at Apple, it also fixes a major performance related bug (see section 2.5 for details). 2.4 Where can I get the latest version of the Express Modem software? The latest versions of the Express Modem CDEV available when this ‘goes to print’ is 1.1.2 and it can be found in the Apple Macintosh System Update, version 2.0.1. This is available directly from Apple and on most online systems. 2.5 How much memory does the software take up? The Express Modem control panel takes about 81K of system heap and about 16K of high RAM as an INIT. But that is not all. When the Express Modem is switched on in the Control Panel an part of it gets loaded as an invisible bakground application which takes about 450K! (This numbers can vary). When you turn the Express Modem off, the application quits and frees up some of the RAM, depending on how fragmented your RAM is. The big catch here is that while the EM get turned on automatically the moment the modem is needed by a program, it will not quit automtically when you are done with it. In other words you have to open the control panel and choose ‘off’ you want to reclaim the RAM taken up by the program. HINT: If you think this takes too much time you can send a ‘Quit’ appleevent to the invisible Express Modem application using something like QuicKeys, AppleScript or Frontier. NOTE: Your modem will not answer any calls when the modem is off in the control panel. eg. you will not recieve any faxes. If you are running with an older version of the EM CDEV than 1.1.2, another reason for wanting to turn off the EM is that it takes up quite a bit of the CPUs time. When the modem is transfering data the CPU has to do the work compressing the data and providing error correction. During data transfers you will probably notice this as a signficant hit if you try doing something else at the same time. Unfortunately a bug in the software used to mean that the EM also grabbed some of the CPUs attention when not in use! Although this bug has not been officially acknowledged by Apple unofficial sources at Apple claim that a polling loop that inadvertently slipped through in previous releases was removed from 1.1.2. 2.6 What is the Express Modem Tool? The Express Modem Tool is a Communications Toolbox (CTB) tool that can be used in programs that use the CTB to make connections. It is very similar to the Apple Modem Tool, but has been configured specifically for the EM to ensure correct setup for most connections. You don’t have to use this to use the modem, but it usually makes things simpler. Apparently there is an incompatibility between version 1.4 of Eudora and this tool, but you can use the Apple Modem Tool to get around this. So far I haven’t heard of any other incompatibilities. 2.7 Does the EM have a magic initialization string? For some reason you quite often see what I call ‘the magic initialization string’ for a particular modem posted to the net. This string is the supposed magic formula that will guarrantie you successful connections at all times (it almost seems that lenght has some relevance, as in “Ha! My initialization string is longer than yours!”). Without denying the the fact that sometimes you need to tweak the modem configuration to get the desired results, fact is that most of the time you are probably best off with factory settings. The magic string for the EM is therefore “AT&F” which restores these settings. 3 The PowerBooks 3.1 Why did my Express Modem stop working on my PowerBook after I reinstalled the system? To use the Express Modem satisfactorly on a PowerBook you need to have at least version 7.1.2 of the Powerbook control panel installed. This is installed when he Express Modem software is intalled from disk. A common problem occurs when the system on the powerbook is reinstalled after the Express Modem has been installed, because the system disks usually contain an older version of the Powerbook control panel which overwrites the newer one. You should reinstall the PowerBook CDEV from your Express Modem disk or from Apple’s System Update 2.0.1 after you have reinstalled the system (the System Update contains version 7.1.3 of the Powerbook CDEV). 3.2 Why does ARA insist that ‘the port is busy’ when I know it is not? See section on Internal or Exernal Modem below. 3.3 What should I leave the “Internal or External Modem” radio buttons on in the Powerbook CDEV? In the Powerbook Contol Panel version 7.1.3 or earlier, there is a section labled “Modem” which has two radio buttons labeled ‘Internal Modem’ and ‘External Modem’. This is probably the poorest documented aspect of the modem configuration, and the manual even contains some very misleading, if not directly wrong instructions (eg. p.35). In most cases you would want to leave this on ‘External Modem’ (sic.). Since this is not very intuitive (the EM is an internal modem right?) it is worth explaining a little further. Most macs have two serial ports, and it used to be that if you wanted to attach modem to your mac it would be connected to either one of them. Communication programs only had to know which one of the two to use. However, it was soon discovered that this wasn’t always satisfactory. First you had the question of what to do when users added more serial ports to their macs using expansion boards, and then when the internal modems came out, how to tell the programs to us them and not send thedata out the serial port. To solve this problem (and some others) Apple came up with the Communcations Toolbox (aka CTB). The CTB allows any number of ports to be available, not just the two standard serial ports. That means that any program that uses CTB port selection will let you chose whatever ports have been registered with the CTB. Thus if you have an internal modem you should get an ‘Internal Modem’ option in addition to the serial ports in the CTB port selection phase. Most recent commercial communication programs, and quite a few shareware programs, use CTB port selection, but what about the old software that doesn’t know about the CTB and assume that just have a standard modem and printer port? Well, Apple thought about that and decided to make it possible to use those too. In order to do that you have to fool the old program by taking the information it thinks it is sending to the modem port and passing it on to the internal modem instead. This is exactly what you are telling the computer to do when you make the ‘Internal Modem’ selection in the Powerbook control panel. Sounds great? Maybe not. When you do this there is no way of telling the redirected information from something you might actually want send out the serial port and not to the modem (eg. connect to a printer or a localtalk network). For Duo users this might prove to be crucial as they only have one serial port on their computer when undocked. A more appropriate labeling of the buttons should have been something like ‘Redirect serial port to internal modem: on/off’. UPDATE! The newest version of the PowerBook CDEV that comes with the new Duo’s and the type II batteries apparently has changed the labeling of this feature. They are now labeled ‘normal’ and ‘compatible’, representing the old 'external' and 'internal' buttons respectively. Apart from the labels there has been no changes in the way these options function, but apparently the new manual does a better job of explaining things (or at least the blatant errors have been corrected). In most cases you will probably find that your applications understand CTB port selection, so you should leave the control panel set at ‘External Modem’. When you do you will find both ‘Internal Modem’ and the usual serial ports available when you set up your communications program. If you have selected ‘Intenal Modem’ you will only see the serial ports, and while the program will work with your EM with the port set to the modem port, you will not be able to use the physical modem port for anything. One thing to note is that there are quite few programs out there which are CTB port selection capable without using other features of the CTB. For example, just because a program doesn’t let you use the Express Modem Tool doesn’t mean it doesn’t use CTB port selection! For example, the popular shareware program Zterm uses the CTB for port selection and will work perfectly well with EM in the ‘External Modem’ mode, even though it doesn’t use the CTB for other things. The same is true of Appletalk Remote Access (ARA). If you set the Powerbook control panel to ‘External Modem’ you will be able to choose the ‘Internal Modem’ in the port pop-up in the Remote Access Setup. If you do it otherwise you will probably find yourself stuck with the ‘Remote Only’ option in the Nettwork control panel on a duo (because you have disabled the printer/localtalk port by redirecting information from it to the modem) or unable to get ARA running, all of which is avoidable! Other common programs that can use CTB port selection are: MicroPhone Pro, VersaTerm, MacIntercomm, FirstClass Client, MacPPP, InterSLIP etc.