Revise the Instructions for the New 56K PC Card Modem

The instructions for the initialization of the new PC Card modem from Thaddeus Computing, Inc. uses ATS37=29. What this does is limit the upstream rate to 56,700. I think this is very fast for the Palmtop, and probably it is adjusted during negotiations down to about 25,000. I believe that in the US, modems may not upload at more than 51,200 legally, per FCC rules. I had to use S37 value of 28 just for the handshaking to go right.

The instructions also add a DT after the S37 specification. This alone means Dial Tone. This is usually part of the dialing sequence - ATDT5553582. Adding it in the initialization makes no difference but it can confuse people.

The W2 means "report the actual modem-to-modem connection speed". With W1 you get the modem to terminal (200LX) speed, which could be faster and it usually is the one in the S37 register.

I suggest that you change the instruction sheet with the following:

1. Take out the DT in the first initialisation string you mention.

2. Then you have a sentence "Note that most software...." This is not really correct. Almost all the programs I have seen, even going back to old, old DOS days, have one string for initialization, and another for the dialing number.

The part that software requires the phone number immediately after initialization is never true in any of the software I have seen run on the Palmtop.

I'd state it like so: "If your software requires that the number be placed with the initialization then use this ATW2S37-29DT5553582."

Avi Meshar

http://www.dasoft.com