An Interview with Jerry and Til Chamkis of AERCO

I took a short vacation to Austin. A morning to drive down in. The rest of the day, that night, and the next day were spent in Austin. Spend that night and drive back to Fort Worth the next morning. (I said it was short!) I took my wife and two daughters. (Sо I was wrong about it being a vacation.) I was able during that one day to stop in and talk with Jerry and Til Chamkis of AERCO. They knew of other members: Frank Bouldin, Charles Stelding, and Ben Jackson. When I got there, Jerry, the lead man at AERCO, was out running some errands, so I put most of my questions to Til. I had numerous questions about the AERCO FD-86 Floppy disk interfaces and received many answers and much information. Jerry came back just as I was getting ready to leave. I stayed while he “booted” the dual drive system with the 256K of RAM, CP/M and the ADD VIEWPOINT terminal. He showed me the 80 column output and the directory on the disk that comes with the system. One of these programs, Jerry told me, when ‘unsqueezed’ takes up over 90 pages in a book. That іs some system!

Since Charles Stelding has the full system, but was having problems with the CP/M MODEM 7 COM program, I asked about what might have gone wrong. І was told that the MODEM 7 or the 750 СОМ program that is provided with the system (they use the standard XMODEM protocol) was a little ‘rough’ since it was being used with the 2050 modem. It can be improved, but most of the ‘bugs’ should be worked out. Both Til and Jerry said that with an RS232 port and a stand alone 1200 baud modem (using their CP/M and drives) you should be able to run almost any COM program including the one’s with XMODEM, KERMIT, МЕХ and others.

When asked about problems upgrading the original 64K to 256K of RAM, I was told there were bound to be problems іп the beginning particularly because of static damage to the chips. In changing the chips for the upgrades the new ones are denser and can cause problems. With the proper care and being careful about static charges being built up, there is a very slight chance of this taking place.

I asked about the necessity of the ADD VIEWPOINT terminal and found that it was necessary for using the 80 columns for CP/M. You can see it in 64 column, but it is more difficult to read. The terminal takes care of that. Timex had an assembly program (AROS or LROS, I am not sure which) for 80 columns (not the 64 columns mode with the 8 blanks on each and equalling to 80) in the 2068 Technical Manual, but it was never really developed. I was told that the terminal really only used the microprocessor and the clock essentially from the 2068. Everything else is on the interface board and the terminal and programs. You obviously need a good monitor to use this. It is possible, since they have a built-in RGB interface on the board, to use one of the better RGB monitor.

I had heard about some difficulty with the MTERM II COM program not working properly with the interface for the disk drives. I was informed that there us» no ‘real’ problem, just the 5V PIN for the computer could cause some problems if it was, as it is in some 2068s, weak. They gave mе a modification sheet for the correction. (See FIG.1). I asked about using the LOACER V program with the TSXMODEM from Kurt Casby with the MTERM II. No problems, a few changes are necessary in the BASIC that takes care of the whole thing.

What kinds of problems are there іп using the CP/M 2.2 operating system? Virtually none, was the answer. For a disk-to-disk copy of programs, there may be a problem. Not all CP/M 2.2 systems are the same, and then they are the same. It depends on the format being used. The onе that Jerry uses emulates a MORROW MD3. Some people have even gotten disks for the MORROW MD3 and run them directly on the AERCO FO-86 with no problems at all. Іf you have the same format-number of tracks, vectors, how the sectors are numbered and such, then there should be no problem. So not all CP/M 2.2 formats are the same. If you are not doing a disk-to-disk copy of progrmas for CP/M, instead using up or -downloading from a BBS, then there should be virtual compatibility.

I asked why the OS-64 cartridge won’t work using the СР/М system. The system uses bankswitching and switches the bottom 0K of the ROM into Chunk 0 of the DOCK BANK. There they modify the ROM to make corrections to the many ‘bugs’ to be found there. Since the OS-64 cartridge uses the DOCK BAMK, there is some incompatibility. This is why the OS-64 and many Spectrum Emulators, which use that DOCK BANK, won’t work-for now. I have heard about someone who has the system with the 256k RAM configured for 4 drives that can use the OS-64 cartridge. The LROS set-up that is necessary will soon be completed.

I then put my final question to Til, how good is your CP/M system for use as a CP/M system and not worrying about it being a Timex 2068? The answer was even better than I had expected. You should be able to upload and download all the files from a CP/M BBS (like the Kaypro MBBS) and use them all. That means using the special ‘squeeze’ programs to compact the program, the ones to ‘unsqueeze’ the programs, the ARC files, the EXE files, the .LBR files, all of them should pose no problem. I believe that if it was configured to run on a specific terminal and system, there might be a problem, but nothing that cannot be figured out. That even includes using all of that extra RAM in the 256K. The only reason that no one is using it is that there is no software available, as yet, that takes advantage of it.

I left Jerry and Til with some information about the newsletter, our group and the FWKUG MBBS and PSDE that has a Timex area. Jerry told me that CP/M was not dead and neither was the Z80 chip. It seems that CP/M is the “hacker’s” choice and the Z80 is the machine that his is most prone to use. There are thousands of great public domain programs out there for our use. If you get some disks in 8″ format, which the system will not read, and want them onto a readable 5 1/4″ disk, Jerry and Til will do it for you for $5 a disk and given the necessary information.