xmodem and ymodem repeat initial block
Eröffnet am: 2019-10-10 22:50
Letztes Update: 2022-04-12 21:44
| Auswertung: | (Anonym) | Verantwortlicher: | (Keine) |
|---|---|---|---|
| Priorität: | 5 - Mittel | Meilenstein: | (Keine) |
| Typ: | Fehler | Schweregrad: | 5 - Mittel |
| Komponente: | Tera Term | Status: | Offen |
| Lösung | Keine |
Einzelheiten
Both xmodem and ymodem repeat the initial packet of a transfer even though the initial packet is acknowledged. In the case of xmodem, packet sequence 1 is sent, acknowledged by the receiver, and then sent again by tera term. In the case of ymodem it will be packet sequence 0 with all the file info that is sent, acknowledged by the receiver, and then sent again as if the receiver had NAK'd it.
Kommentar
I was able to build and run the Tera Term source code for Tag 4.106 and came up with a potential fix for this ymodem bug. The issue is that if the user takes a while to use the file dialog to select the file to send, multiple 0x43 ('C') will be received from the remote device and Tera Term will respond to all of them (causing remote device to send a NAK) when it should only respond to a 0x43 once for start of transfer. The fix is very simple and stops Tera Term from responding to more than one 'C' in a row. I tested it with my embedded system and the fix seems to work well. Feel free to use it if it's acceptable.