Boxcar RS232 DSR dump needed

[atrax27407]

I have what may be a DSR dump of a Boxcar RS232. However, it is very odd looking when viewed with a hex editor. I need a verified dump (i.e., one from a known Boxcar RS232) to compare it with. Can anyone help? Send the DSR dump to: Rmcarmany@aol.com with "Boxcar" in the subject field. Thanks.

[atrax27407]

I got a verified dump of the DSR. Exactly how it works is a mystery. It doesn't look like any DSR I have ever seen!!

[+mizapf]

Show us?

[atrax27407]

OK --

bxc_rs232.bin

[Stuart]

Is that read direct off the DSR EPROM? Do you see the same data if you look at the DSR using MiniMem EasyBug? (Wondering if the address/data lines to the EPROM are jumbled, so that it reads correctly in situ.)

[atrax27407]

It is a direct read off the EPROM from a working unit. It is also identical to a file that I got 16+ years ago from the Lima UG library.

[Stuart]

The data lines to the EPROM are jumbled. If you re-order the bits in each byte as follows then it all makes sense:

 

Original data: D0-D1-D2-D3 D4-D5-D6-D7

EPROM data: D1-D5-D7-D0 D4-D6-D2-D3

 

For example, the first byte of the DSR header is AA (1010 1010), and this is 1E (0001 1110) in the EPROM.

[atrax27407]

Bad engineering or attempted subterfuge?

[+jedimatt42]

Bad engineering or attempted subterfuge?

 

Well, sometimes it is easier to route the traces for a board if you can re-assign the pins on a device. The pin order on the sideport for these signals is in a pretty crazy order. That said, doing it on purpose to something like an eprom that requires a contract with another device, is evil. If their goal was subterfuge, then it was clever. If their goal was to save a batch of pcboards that were designed wrong, then it was resourceful. If their goal was to just be easier, then I'd call it lazy, but that is me being judgmental, without any knowledge of 1980s EDA tools.

 

I just did this on my TIPI project, but that was a MISTAKE. Not intentional, will be corrected before release.

 

-M@

[apersson850]

Do you have the unit in question? If so, disassembling from the device would give you the right listing. The memory chip doesn't care which data bit is used for what. It's only a problem if you read it, or write to it, in a different way.

[Swim]

Seems a nice project for this device would be to add higher baud rates than 2400.

[atrax27407]

Go for it, Richard!

[+acadiel]

I have one of these. Will need to find it. Maybe someone can in unobfuscate the order of the bits and "fix" the image.

[atrax27407]

Due to the efforts of Richard Bell, we now have a dump of the Boxcar RS232 as seen through the scrambled address lines as seen from the console. However, to burn a replacement EPROM one would still have to use the one previously posted. Here is how it appears unscrambled.

boxcar.bin

[+acadiel]

Due to the efforts of Richard Bell, we now have a dump of the Boxcar RS232 as seen through the scrambled address lines as seen from the console. However, to burn a replacement EPROM one would still have to use the one previously posted. Here is how it appears unscrambled.

Awesome! Glad he got to the unscrambled one. I was about to do a mini memory dump

 

I dumped mine for comparison too, it has "V1.1" on it.

bocxar_e232_v1.zip

[+acadiel]

 

In case anybody be wants to see this.

 

The AC adaptor is 9V, 200ma, positive tip.

[+Schmitzi]

thanks for the PSU info. "tip" means the pin insight, I think.

 

(Have 80 PSU´s in the list now, there in 44 for the console)

[+InsaneMultitasker]

Wrote a quick and dirty Geneve program to scramble/unscramble the EPROM.

Acadiel's v1.1 appears to be the same as what Swim dumped.

If you update the baud rate table, I can scramble the binary so that you can burn it.

 

To unscramble the EPROM contents, the bits are re-ordered as follows:

EPROM[abcd efgh] -> [dagh ebfc]

[+acadiel]

thanks for the PSU info. "tip" means the pin insight, I think.

 

(Have 80 PSU´s in the list now, there in 44 for the console)

Tip is literally tip in this case. It's a standard mini 3.175mm tip/sleeve connector.

[atrax27407]

Insane Multitasker and I "double teamed" the Boxcar RS232 file. I took the existing "clear" file that we got with the DSR dump through the console which was unscrambled and altered the baud rates. The original went from 110 bps to 9600 bps. The table had been truncated by one value. I changed the baud rates to go from 300 bps to 19.2K bps I sent the file back to him and he re-scrambled it so the it could be burned directly into an EPROM (TMS2532).

 

Remember, this file is completely untested. Someone with a Boxcar RS232 will have to try the new baud rate table out. There are no guarantees that it wll work properly. Pleaae post your results (and system configuration) so everyone can share in the "fun"

BOXCAR_HS.bin

[Swim]

Nice work guys.

 

Of course I am working dawn to dark this week on the real job so unless it rains I will not be able to burn an EPROM with this new .bin until later in the week.

[+InsaneMultitasker]

Remember, this file is completely untested. Someone with a Boxcar RS232 will have to try the new baud rate table out. There are no guarantees that it wll work properly. Pleaae post your results (and system configuration) so everyone can share in the "fun"

Once the changes (and scrambling) are confirmed, I'll post a disk image with the program source/executable and the DSR images.

[Swim]

 

In case anybody be wants to see this.

 

The AC adaptor is 9V, 200ma, positive tip.

 

Hmmm? I don't see a wire tying pin 21 and 24 of your EPROM acadiel? Is your pin 21 lifted from the socket or trimmed off? Ah, you have a revision "A" board maybe that's why.

[+acadiel]

 

Hmmm? I don't see a wire tying pin 21 and 24 of your EPROM acadiel? Is your pin 21 lifted from the socket or trimmed off? Ah, you have a revision "A" board maybe that's why.

Nope, no wire that I can see.

 

Sent from my Moto G (5) Plus using Tapatalk

[Swim]

Perhaps the black case could indicate earlier board versions.

This didn't go well. I just learned "My Media" reduces the size of pics. This board has hand wiring and the EPROM has pins 21 and 24 strapped with the leg of pin 21 bent out so it doesn't make contact with the socket. acadiel's board is a version "A" and shows no hand wiring or strapping of the EPROM.

So far, I'm unable to successfully test atrax27407s high speed .bin. I can program the EPROM successfully but the EPROM does not function as expected when connected to the 99/4a console. Will investigate further as time allows.