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  It's funny. I thought I was close to finishing an mTCP release. And then I started updating the NetDrive protocol spec to document the changes. It's been 3 or 4 days now of fixing it and fixing code to make it coherent and consistent. And I probably have another week of work to do. It's stupid things, like "Oh, a 16 bit CRC is fine for line noise but not for verifying a large block of data was written correctly." Or making sure the protocol changes are kind of future-proo...

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  mTCP is now officially on github! I was resisting for years but there are too many out of date or incorrectly forked versions out there now, so providing an official copy to fork from should be beneficial. https://github.com/mbbrutman/mTCP.git #Retrocomputing #Retrocomputing

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  Does anybody need an IBM PCjr postcard? #retrocomputing

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  My networking gear has always celebrated ... #PrideMonth #Retrocomputing

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  I wrote my first DOS TSR recently. It's a rewrite of the DaynaPORT SCSI Ethernet adapter packet driver, this time in pure x86 assembler. The original version was written in C which worked but it required 29KB when it was resident. The rewrite requires 3.5KB, which is quite an improvement. I also found it much easier to write a TSR in assembler, as I was able to do things directly instead of working around the C compiler. I should post this as a new skill on LinkedIn. ;-0 #retrocomp...

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  VCF PNW 2026 is one week away! https://vcfpnw.org/ May 2nd and 3rd, Tukwila, WA (just south of Seattle near the SEATAC airport). Sponsored by the Interim Computer Museum. #retrocomputing

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  I'm having way too much in retirement. While the soldering and coding are fun, the small extra details like funny business cards make it absolutely delightful. #retrocomputing

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  I spent two long days coding streaming writes for mTCP NetDrive. I have some early results. The test: Copy a large file (1.7MB) from a 386-40 with an NE2000 card to a Linux server about 1800 miles away. Old code: 18KB/sec New code: 214KB/sec The new code is about 350 bytes larger and uses no additional memory on the client side. On the server side I just had to increase buffer sizes. And DOS is none the wiser .. the remote server just looks like a drive letter. #retrocomputing #mtcp

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  Attn: DOS PC users using EtherSlip for networking: I have a new version of EtherSlip available that fixes two bugs: * The incorrect MAC address was being set in the simulated Ethernet header. This broke mTCP NetDrive and possibly other programs. * The code in EtherSlip that simulates ARP responses has a pointer bug in it. This can cause data corruption or crash your program any time it tries to send an ARP request. A fixed version can be found at https://www.brutman.com/Device_Drivers/packet...

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  Like to read about hunts for pre-historic bugs? I've just posted my notes on how I found a 35+ year old bug in DOS 3.3's SYS.COM. https://www.brutman.com/Adventures_In_Code/DOS_33_SYS_Bug_Hunt/DOS_33_SYS_Bug_Hunt.html #retrocomputing #DOS

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  VCF PNW 2026 is just a month away! https://vcfpnw.org/ May 2nd and 3rd, Tukwila, WA (just south of Seattle near the SEATAC airport). Sponsored by the Interim Computer Museum. #retrocomputing