Hacker News new | past | comments | ask | show | jobs | submit login

In my younger years, I had to pull a dBase 2 database off a CP/M desktop into an MS-DOS portable.

I ended up configuring a serial cable, and running PROCOMM on the PC, set 9600/n/8/1 on both ports, then printed from dBase 2 and set PROCOMM to record the session to a file.

It would lose characters if I let it run too long without a pause to write to a floppy, so I would ctrl-s/q on the CP/M side.

I guess nobody else had ever figured out how to do this.




I think in this particular (macbook) case the problem was lack of proper software. Yet, I recall if there was modem installed, a terminal software had to be present as well.


The CP/M side didn't have any terminal software. Both sides had methods to set 9600/n/8/1 on the printer device.

On the PC side, without PROCOMM, it would be possible to "COPY COM1: FOO.TXT" but I don't know how 9600/n/8/1 could be set in advance (IIRC setting it as a printer to force the baud rate altered the device so it could not be read).

Generally speaking, all of the pre-PC microcomputers implemented serial ports, which is the first choice in pulling data off of them (including binary data with XMODEM and its variants).


Yes, you can transfer files via COM port in MS-DOS using COPY command, but errors may occur. :) Also you have to switch port to 8-bit binary mode and turn off flow control. Don't remember how to do that exactly. Default was 7 bit XON/XOFF, AFAIR.


Looks like it's the MODE command: https://home.csulb.edu/~murdock/mode.html


Is it so hard to write your own program which would just read a file stream and send it to a port? Maybe also split it into smaller frames with CRC hashes attached.


Depends: I wonder what programming tools/languages were present on the old PowerBook. Otherwise, getting any handwritten program or its associated tools/runtimes (if necessary) onto the laptop might be just as much of a challenge as getting audio data off.


Just program directly on the macbook! :D would be fun to experience imo


CP/M was an OS for the 8080/Z80, which was limited to 64k of RAM.

None of the tools that you know today would work in something that small.

There was a C compiler for a dialect of C that met these constraints; I didn't have it, and I didn't know C at the time.


`cat file > /dev/com1`, or something like that.


Isn’t this a pre unix mac?




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: