“Phoenix Pete” Fischer is THE GURU of TS-2068 Telecomputing, having written a book on the subject. Thanks “P.P” for this nice input. Your expertise is always welcome in the pages of UPDATE!
ABSTRACT: This is a review of MakeDOS-64, a machine code system which allows use of the OS-64 cartridge code on an AERCO Disk Drive without loss of Aerco DD commands, and with access to the full 256K ram via bank switching. (review by Pete Fischer)
Short Description of DOS-64
DOS-64, like the OS-64 cartridge itself, sits in the Dock Bank. However, it DOES take away a small portion of ram in the Home Bank. It features the full use of AERCO Disk commands, just like the AERCO version of OS-64, but that version gives you only 17K of BASIC area. This version keeps the normal 33K that OS-64 would leave you. It also includes a number of other features not found in either the Aerco DOS nor the OS-64. Read on!
Description of the OS-64 Cartridge
Before I go into MakeDOS-64 itself, though, let me describe the OS-64. It’s not as cut and dried as it first seemed. True, you just plug it into the cartridge port & turn on the machine. But it’s not QUITE that simple. For one thing, you’ve lost nearly 5K of free memory at the bottom of BASIC. This is never discussed in the Zebra docs. Thus, loading any program longer than 33+K will crash the 2068. Also, you’ve lost some of the commands in BASIC. FLASH is useless, since it required Display File 2 in order to work. Once you set either PAPER or INK, the other is set to it’s compliment. (i.e. PAPER 4 [green] will set the INK to 2 [red]). This change effects all the ink on the page- so that it’s impossible to have more than one color of INK on any page. Also, you can’t change the BORDER to a different color than the PAPER. You also lose BRIGHT and INVERSE.
Jeff Street, the Zebra programmer who wrote OS-64, DID manage to include printer drivers for 4 centronics interfaces, namely, the Aerco/Oliger, Tasman-B, Tasman-C and A&J. The 2040 is NOT supported. These are meant to drive Epson- compatible printers. But you can also load your own custom driver, and the docs tell you where to load it and how to call it (can be either centronics or serial).
Since screen display uses display file 2, a normal SCREEN$ will not work to SAVE or LOAD. You must SAVE/LOAD two seperate CODE files in order to deal with a SCREEN in 64 col mode.
At first I thought a BASIC program had to be specially written for OS-64. But then I thought, why don’t I just LOAD in a program written for 32 col.,and see what happens?
So I did, and to my surprise and delight, most things worked. There WERE problems; such as when a program used 2 or more INKs in the same menu. The screen would flash through all the different colors as it printed out the screen, finally ending up with green ink and red paper which was unreadable even on my RGB. So I had to fix all those (this can take some time on a long program).
Any text which was centered in 32 col. is now to the left, and depending on how the PRINT command was used, some lines of text may stop at 32 col, while others go on to 64 col. So these PRINT statements may need some editing. But once you’ve converted a program, it’s done. You never have to do it again.
So what is the advantage of 64 col.? The first attraction to me was the capacity to run Zterm-64. But the small buffer and bugs made that program less appealing.
It lets you put twice as many columns on the screen, with the same number of rows. This doubles the information on a page. This is particularly useful when you’re using software that stores and displays lots of data, such as word processing, spreadsheet, accounting, database or telecommunications. It can make much better menus, as I always seem to run out of screen before I run out of options. You will see less of the “scroll?” prompts on your screen. Although I can’t help but wish we had more rows as well as more columns…
One last note on the OS-64, if you have the JLO disk drive, you need to have OS-64 ver 1.72 in order to use the NMI “snapshot” save.
The Difference Between OS-64 & DOS-64
The main difference is complete compatibility with the Aerco system without any loss of free ram. Also of critical interest is the access to the full 256K rambank via bank switching. These banks can be had by a simple OUT command. Oh, what wailing and gnashing of teeth could have been saved if Aerco had sold this software with their 256K upgrade! (NOTE: In his recent book on advanced M.Code Programming on the 2068, Dr.Lloyd Dreger discusses this scheme of access to the 256K. He gives credit to David Hill. Keith Watson wrote the code originally, and gave it to David to publish in his newsletter. This is just a misunderstanding on Dr. Dreger’s part).
Another feature that Keith worked in is a program by Jack Dohaney called KEYWORDS. For those of you who are unfamiliar (as I was) this program allows you to enter the TIMEX BASIC keywords, one letter at a time. This is useful to those who have custom keyboards without legends. You can toggle this feature on and off with a PRINT USR statement.
There are two additional character sets, BOLD and IBM PC style. These improve readability on marginal monitors.
You can alter the total maximum number of directories on a disk. We always complained that 31 was too few. But now that the number is doubled for DD diska and tripled for QD disks, it seems to take a significantly longer time for the system to search a directory. This gives you the best of both worlds.
While it’s true you can “customize” the OS-64 cartridge for a large number of options, you do so using POKE statements which must be re-entered everytime you turn on the computer. Since Make-Dos comes off a disk, however, you can customize it once and for all (and easily re-configure it later). Then, you save the customized version and DOS-64 “Wakes-up” in any setup you want!
This “customizing” is done by a menu-driven program that’s quite painless and easy to follow. This is MakeDOS. All four of the original printer drivers are still there. You can choose one of those, or your own custom driver as permanently enabled. You can also choose various printer configurations such as line length, and print density. There is also an option to increase the total of numbered lines in BASIC from 9999 to 16383.
THE GOOD POINTS
1. Permanent 64 Col. display with completely normal DOS operation.
2. Full access to the 256K ram upgrade.
3. All the original printer drivers of OS-64 are there and any one can be permanently enabled.
4. There are 2 new character sets.
5. Jack Dohaney’s KEYWORDS program is available for use.
6. Most 32 column BASIC programs are compatible, or require minor modification.
THE BAD POINTS
1. I miss a hardcopy manual for this product. You don’t need one much, but it’s good to have.
2. Some of the explanations given on the help screens are a bit technical. For technical users, they will be welcome. But others may be thrown.
3. You lose about 5K of BASIC (which you also lose with OS-64)
“I was just writing something for my own uses.” That’s how Keith described it to me in his self-effacing manner. He ended up spending several hundred hours and many calls to AERCO to get the straight story on the 256K. How many really great software packages started out as someone writing something for their own use.
This software is available from RMG, who has gone to great lengths to support AERCO users. It costs $15 +$2 P&H. Or from Keith. Brilliant programmers are worth supporting. See pg 14 of January UPDATE for addresses of Suppliers.