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TRS-80 Model 1 won't boot from disk

Hi AndyDiags,
I worked several years on my US version Model 1 without a functional interrupt. The only thing I was missing, was the CLOCK function. Especially the floppy access worked fine without having the interrupt capability.
From my US version ROM V1.3 I know that the NEWDOS80 V2.0, I am using, is accessing fixed addresses. As I only created WAV files from US versions of the operating systems, you might run into an incompatibility of the disk OS and the ROM content. Do you have a Japanese OS version that you can use for testing?

Regarding Bootstrap
The program is checking the content received via the cassette port. It is verifying each sector written to disk and it is verifying itself after finishing the creation of the floppy. It is very unlikely that an error might be missed on the path.
 
Your Floppy Drive has a Switch S7 with six toggles. What is the function of each Toggle?
I can almost see that Toggle 6 is HM (Head Sol'nd Load with Motor ON), Is the following
assumption correct?

You have toggles 1, 2, and 6 "ON"

1. HS (Head Sol'nd Load with Drive Select)
2. DS0 in a DS{0..3} configuration (On my M1 DS3 Can NOT Be used.)
3. DS1
4. DS2
5. ??
6. HM (Head Sol'nd Load with Motor On)

Try Booting your Computer with just Toggle 2 "ON" = CLOSED for DS0.

Attached is my MPI 51-52 Floppy Shunt for Drive Select.

Also on Most Computers the Terminator is installed on the last Floppy Drive on the cable, which
would be DS0 if you are only using one Floppy Drive. (I forget where my Model 1 has the
Terminator installed. I can't look at it until early April.)


Larry
 

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Is the Japanese Model I the TEC with the Kana keyboard? I have one and none of the operating systems I tried work. George added support in trs80gp and had to patch TRSDOS 2.3 to work with it.
 
dittman said:
Is the Japanese Model I the TEC with the Kana keyboard? I have one and none of the operating systems I tried work. George added support in trs80gp and had to patch TRSDOS 2.3 to work with it.
Click to expand...
This!
I thought the Japanese TRS-80 just had a different character set, but the ROM and its mapping is different so that regular DOS systems won't boot.

There's no archived copy of a Japanese DOS disk. My system did come with a disk drive and a floppy inside, I'll try to dump it to see if anything useful is there.

@dittman, can you please share the copy of the patched TRSDOS 2.3?
 

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Here's TRSDOS 2.3 patched to work on a Japanese Model 1.

Any luck dumping the diskette? It'd be great to have the real TRSDOS for it.
 

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Thanks! That's fantastic. It works in trs80gp. A quick scan shows at most 100 bytes difference in the various files on the diskette from TRSDOS 2.3. And all indications point to it being a patched version as opposed to having been re-assembled from source. Will have to do a deeper analysis at some point.

Where did the picture of the diskette at the start of your page come from? Was that the original TRS-DOS for Japan diskette or some kind of mock-up?
 
gp2000 said:
Where did the picture of the diskette at the start of your page come from? Was that the original TRS-DOS for Japan diskette or some kind of mock-up?
Click to expand...
It's the original image from an ad. In 1981, Radio Shack ran some ads in popular Japanese microcomputer magazines. I got the image from one of those ads. Examples are here and here.

I think that maybe the Japanese TRS-80 was initially released with TRSDOS 2.2, as I see it mentioned here in a 1979 issue of Microcomputer.
I couldn't find any other DOS (e.g., LDOS, NewDos) mentioned anywhere in any magazines. I think TRSDOS was the only DOS ever released in the market.
 
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