WiModem232 works great until file transfer
#1
Ordered the WiModem232 early in the week, got it today. Set it up and logged into a dozen BBSs. This thing is pretty awesome! What a way to relive the "good old days"! The only thing missing is the dial and connection tones, lol! The only issue I am having is that when I try to do a file transfer, using Xmodem, Ymodem, Zmodem, etc, the transfer never starts, just keeps erroring until it eventually fails. I tried AT*T0, AT*T1, and AT&K1, with no help. The BBS screens load with no issues, no corrupted ANSI garbage, it works perfectly until I try a file transfer. I'm using a Tandy 1000 TL/2 with a dedicated 16550 serial card, WiModem connected directly to the port, no adapters, and I've tried Procomm Plus and Telix. Any ideas what I can do to get downloads going with this?
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#2
You need to enable flow control on your terminal program if you are using a baud rate higher than 2400 baud.
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#3
Depending upon your software, you may be able to see the menus without issue at the higher baud rates, but with file transfers, your software and/or computer may not be fast enough to sustain higher transfer rates.

I was working with a terminal program that at 38400 baud, no issue displaying the menus. However, with file transfers, I could not go above 4800 baud. After playing with the source code for weeks, it was just night I overcame the issue and was downloading at 38400 baud.

That software had several "gotchas". One, no RTS/CTS. Two, the status line with clock info on the bottom of the screen chewed up too many CPU cycles at the higher baud rates. Three, keyboard checks for Aborts took too many CPU cycles. And fourth, the "byte" counter/odometer showing how many bytes transferred was chewing up too much time when it rolled into displaying 5 and then 6 digits of file size.

All hurdles. I still do not have the RTS/CTS quite right, but I finally got the transfer speeds to download at those higher baud rates. Keep in mind years ago some of the older Terminal software may have been written to handle no more than 2400 or 9600 baud rates. Faster hardware just was not available. And, with Telnet capability and Telnet BBS's, there is a continuous buffer of data at the modem sitting to be processed and delivered as fast as possible.

Beery
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#4
I tried enabling XON/XOFF flow control, and alternately RTS/CTS flow control on both the modem and the terminal software with no luck. I tried dropping the speed all the way down to 300 baud to see if that was the problem too (forgot how slow 300 baud was!) I even tried the Wimodem on a 486 just to make sure it wasn't the computer. Any other tips that may solve the problem?
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#5
XON/XOFF is not supported.  You should only need flow control at 9600 baud and higher.  Zmodem protocol requires extremely laxed timing due to the Internet latency.  Xmodem, Xmodem CRC, and Xmodem 1K all work fine.  What protocol are you trying to use?  Have you verified that your terminal software and PC work with file transfers for a real modem?

If you are calling a BBS that uses telnet escaping are you enabling telnet mode using AT*T1?
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#6
I had trouble transfering anything with either Zmodem or xmodem. But Kermit works great with the WiModem on my C128 and striketerm or even under cp/m with cp4-c128. Wich makes sense, as Kermit is designed to work with bad connections.
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