This may be of interest to those who are running VICE to emulate a Commodore 64 and using tcpser to bridge serial I/O to the internet:

There seems to be an isssue with how tcpser encodes the carrier status (see post from lemon64.com below), affecting serial file transfers.

I have tried a few of the many forks of tcpser (including the fozztexx one and Jim Brain's original code) and none of them worked when trying to transfer files.

Discussion: https://www.lemon64.com/forum/viewtopic.php?t=72228#top

The solution to the problem was to use a different tool to "bridge" the serial communication: TCPSerial.jar which is a Java based implementation of tcpser. It is an updated version of Jim Brain's Java codebase (tcpser4j) to work with Java 21:

https://github.com/MyDeveloperThoughts/tcpserial/releases/tag/Version1.00

Using this tool instead of the original, C code based tcpser made it possible to finally transfer files using x/ymodem.

I thought I should let you know ... 🤔

#Commodore64
#VICE
#tcpser
#xmodem
#problems
#solution
#TCPSerial

Oh, the smell of 8-bit file transfers from a BBS ...

(on the sending end, at RC-BOX BBS, the CP/M program KMD.COM is being used)

#xmodem
#crc
#CCGMSfuture
#Commodore64
#Striketerm

I pushed out the January 2026 patch of DiskSumo: https://github.com/aakoskin/DiskSumo/commit/9b90634cda9a54bdf52e6b6048ce4e8f6a811fb7

The highlight being that disk read errors are now getting reported - an useful feature in a backup software, don't you think?

#Commodore64 #Floppy #Backup #Xmodem #Retrocomputing

I pushed out a new DiskSumo patch, with my new machine code routines. It's been fun to learn some 6502 instructions, and debugging the code just reading it over and over again using Zaks' book as reference.

Now a floppy disk backup takes only 40 minutes over 1200 bps Xmodem. I'll start a mass effort to back up all my 300 floppies.

https://github.com/aakoskin/DiskSumo/commit/4332018d598d8c130cc6ddd34df2b7b66150db6a

#Commodore64 #Floppy #XMODEM #MachineCode #RetroComputing

Just updated the VIC-BBS to include Xmodem uploads and downloads. There's a complementary VIC-20 terminal program called "Saturn3" that also includes Xmodem upload and download.

So now, VIC-20 users can finally do file transfers without having to rely on a friend with a C64! Keep in mind I didn't test this much, but give it a shot if you're interested.

bbs.deepskies.com:6400

https://github.com/VA3DSO/VIC-BBS

#Commodore #VIC20 #RetroComputing #BBS #BulletinBoardSystem #Xmodem #FileTransfers #Modem #DialUp #80sTech #RetroComputing

I rewrote 2 DiskSumo bottleneck routines in 6502 machine code (against original plan, I started to optimize sending):
- read a disk sector into buffer
- send buffer as #Xmodem packet

With 1200 bps #RS232, floppy disk dumping speed dropped from 90 minutes to 40 minutes, getting closer to line rate.

New machine code inlined in #BASIC lines is under 20 screen lines per routine. This is a "type in" program, so I need to optimize my verbose machine code syntax as well.

#RetroComputing #Commodore64

I pushed out a minor patch to my DiskSumo fork, just to remind myself how the program works and verifying my C64 and 1541 hardware are still OK.

Next goal for me is to rewrite the bottleneck routines in machine code in the following order:
- RS232 character reception polling loop.
- Xmodem packet reception loop & checksum calculation.
- Xmodem packet sending loop.
- Disk sector writes and reads?

https://github.com/aakoskin/DiskSumo

#RetroComputing #Commodore64 #LowEnd #Floppy #XModem #PermaComputing #Slow

Before torrents, before FTP, before high-speed — we had Xmodem, Express! Term, and a whole lot of watching this screen..

Checksum in play
SOH timeouts
NAK’ing blocks like a champ
Mom picking up the phone

If you were there, you know the thrill of waiting 40 minutes for a cracked copy of Donkey Kong to transfer without corrupting.

#BBSing #Xmodem #RetroComputing #Atari #SouthernAMIS #FujiNet #Telnet

Звоним через полстраны по dial-up модему в 2025 году

Приветствую всех! Многие из нас застали лично и всё ещё помнят «модемную» эпоху. И даже мне самому доводилось ими пользоваться, а много позже я писал про то, каково в нынешних реалиях сидеть в интернете через старый аналоговый модем. Но вот мне стало интересно: а как насчёт попробовать позвонить не через мини-АТС, а на модем в другом районе или даже в другом городе? Именно этим мы сейчас и займёмся. Итак, в сегодняшней статье проверим на практике, реально ли заставить два модема связаться друг с другом в наши дни заката эпохи медных линий. Узнаем, насколько стабильным будет соединение и будет ли оно вообще. Традиционно будет много интересного.

https://habr.com/ru/companies/timeweb/articles/812137/

#timeweb_статьи #телефон #модем #gpon #линия #rs232 #uart #xmodem #ymodem #zmodem #crc #ppp #putty #hyperterminal #norton_commander

I missed his passing last year.

https://en.m.wikipedia.org/wiki/Ward_Christensen

#Xmodem