IKS@PSUVM.BITNET (Indra K. Singhal) (08/26/87)
. MNP 5 for Multitech 224EH modems is around the corner. Microcom 9624/c has had it for some time now... Why should you get this $25 or $50 upgrade, as your case may be ? Couple of reasons: . With MNP 3 we essentially got CRC checking at the firmware level... big deal (it was for long distance file transfers over packet switched networks). MNP 4 brought dynamic packet size adjustment and a larger default packet size... this provided smoother text scrolling and better efficiency over noisy lines. (I have a very clean line... I said... Hmmm...) larger packet sizes are nice. It also achieved upto 122% efficiency by optimizing data in its packets (remove start/stop bits at origin & replace at destination when speed conversion is used). MNP 5, hmmm $25. Hmmm. Should I ? . I guess so. MNP 5 does dynamic realtime data compression. If you use your 224EH's speed conversion capabilities, it is said to provide up to 4800 baud throughput over 2400 baud lines. Speed conversion means, your 'puter talks to the modem at 9600 baud while the modem continues at 2400. If you do not use speed conversion, MNP 5 will bring little or no benefit. . To get speed conversion you need to go into your modem and flick a dip switch. You have to enable flow control. Switch 1 on the 4-position switch should be DOWN for CTS to act normally and NOT be forced on (UP is factory default). Then make sure the RTS jumper is set to function normally (which is the default, as per Rev. E User's manual of 1/15/87, page 9-9) and NOT forced on. Finally, the CTS/RTS jumper should be such that CTS follows RTS (again the default, page 9-10). . Now for soft changes. Try the following configuration: &E1 - to set Auto-Reliable mode (see note below) &E4 - enable hardware flow control CTS/RTS &E13 - Pacing on $BA0 - disable baud adjust $SB9600 - serial port baud rate to 9600. Once you have it working, issue AT&W0 to save the config. Thereafter an AT Z will take you to this configuration. AND before you invoke your favourite Comm program, you should issue: MODE COM1: 9600,N,8,1 (or what ever). . How do you know your speed conversion is working ? Get on to your favourite BBS, scan some text in non-stop mode and hit 'Pause' (or PC equivalent CTL-NUMLOCK (??)). You will see the text stop while the RD light stays on. Then hit any key to release the pause and try reading at 9600 baud !!! . NOTE: some cheap modems get very upset at MNP detection data being thurst down their RJ11s. When calling them issue AT&E0 before dialing. *%*%* Have fun !! 2) I have no connectoin with Multitech other than being a happy user. The above is from my head AND I am not liable if you get into trouble for using it... darn skin... have to save it. ------- Keep Smiling (-:-) --Indra K. Singhal >> << >> email : psuvm.bitnet!iks | bitnet: iks at psuvm << >> usmail: 1300 Fayette Street # 243, << >> Conshohocken, PA 19428-1320. << >> ring : 215-646-7710 (w), 215-828-1322 (h) <<
asp@puck.UUCP (Andy Puchrik) (08/27/87)
In article <18989IKS@PSUVM>, IKS@PSUVM.BITNET (Indra K. Singhal) writes: > . > MNP 5 for Multitech 224EH modems is around the corner. I've been following Indra's Multitech adventures. I went for cheap with the "desktalk II" and then the Turbo 2400 EC, both made by Incomm. The Turbo is MNP 4, Hayes compatible, and 2400 baud. I just called them about the MNP 5 upgrade (4800 baud). It should be shipping in 2 wks. The cost is around $200 from the distributor (USA FLEX). More than Multitech, but the Turbo came in for $319. It will be upgradeable to 9600. Looks like comm speeds are going up faster than my phone bills! -- Internet: asp@puck.UUCP Andy Puchrik uucp: {alliant,wjh12}!maynard!puck!asp Moonlight Systems ARPA: puchrik@tops20 Maynard, MA 01754