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Cheapo IDE interface for Model 4p running MM CP/M

Yeah, by the time you put it all together the FreHD, fully assembled and with an SD card, is only about twice its price. But, as Hans' review said, they have their own niches.
 
When you have about 50 parts bins full of IC's Resistors, Capacitors and other electronic components plus cables and such like I do it is cheap. But if you have to go out and source parts it can be a little pricey like hans said. I emailed the seller he built up 8 of them and now trying to recoup his money. In that respect his price is not far off. So I wished him luck!
 
I've got to ask a question about the IDE interface: Can it be used to connect a CD ROM drive to a TRS-80?

Howard
 
@EX5707

Connecting is no problem.
But you need a driver to make it work, just like MS-Dos need.
I have never heard about it, but maybe someone has try to write it.:)
 
The CDROM would need to provide an 8-bit transfer mode for this to work, as with the low-cost adapter we're simply throwing away half the data from each 512-byte sector by using just the low byte from each word, to get 256-byte sectors.

I wonder how parallel port CDROMs worked? Presumably they were 8-bits.
 
It's waiting for someone to experiment with it :) Electrically I think it should work, it will need software of course.
 
James, I have one of the 1.0 Lo-Tech IDE adapters for the Model III. I just have to mount the resistors, then plug in the chips, make a cable, make the boot disk and go...

Your website is still showing pictures of the 1.0 board. I know the 2.0 board has pull ups on the control lines.

Can I use my 1.0 board safely, or should I wait until the 2.0 boards are ready (I'll want three PCB boards)?

Also, when the Model I compatibility is proved out, are you going to make a Model I version with the adapter circuit on-board, or offer PCB boards for the adapters?

If so, put me in line for a couple of those.

I might have to build one of these for all my Model I's as well as my III and 4D.
 
Please don't be insulted, but your adapter costs about twice as much as a Lo-Tech kit costs (currently about $47US for your adapter vs. $21US for his kit), or about the same as an assembled unit. If I had a bare PCB, I can solder two connectors and 4 components myself, as well as make up the cable.

I have extra connectors from building my Lo-Tech board, a couple of resistors and two transistors are pretty cheap.

I'm on a fixed income, and any money I can save really helps.
 
@ Al Hartman

Hi Al
Thanks for the link.
I have used the Trs-Ide unit setup as 2 Operating systems Ldos 5.3.1 and LSDos 6.3.1 on the one hard drive, using 2 Boot disks to access the relevant drive slots.
The unit is very fast ----etc.

I really would like for """ Somebody """ to do a Model 3 NEWDOS Version.

Ray
 
As it happens I just ordered more TRS-80 IDE Adapters - stock is due in about a week.

I need someone with a Model I to take on the programming and testing necessary to get it all to work though. If anyone is interested in doing this, I'd happily provide a pre-built IDE adapter of course.
 
I finished my Lo-Tech Cheapo IDE 1.0 adapter for the TRS-80 Model III/4.

I had to solder 5 resistors. I plugged in all the chips, and hopefully it will just work. I have to make a cable and a boot disk.

One hole for one of the resistors was plugged, and it was a bear to clear, but I got it done.

The R150 resistors I bought were too large, so I had to solder them in standing on one end. I also bought LEDs too large, but I squeezed them in. I don't care as long as they work.

Next, to make the boot floppy, and the cable.

BTW, those disk images appear to be larger than a double sided 5.25" floppy disk. What size were the original disks these were imaged from?

They really need to be lowest common denominator, which would be single sided, 40 track, 5/25" Double Density Disk for a Model III/4.
 
Al Hartman said:
Will my 1.0 board work, or should I just forget it, and save the parts for the 2.0 board?
Click to expand...

The only differences (IIRC!) between the rev.1 and rev.2 PCBs are revised hole placement for the LEDs and different port mapping (40h and C0h for rev.1, 40h and C8h for rev.2). So both should work just fine; I think that the drivers Firebox kindly provided use 40h.

Al Hartman said:
BTW, those disk images appear to be larger than a double sided 5.25" floppy disk. What size were the original disks these were imaged from?
Click to expand...

I'm not sure - Firebox kindly put these together. If you can shed any more light and/or create new smaller disk images, please do so and let me know so that the documentation can be improved as well.
 
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