PSR-800: DMR and NXDN systems

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marksmith

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Explains why you are having a problem. The 800 won't receive those types of systems.

Mark
WS1095/536/436/996P2/HP1e/HP2e/996XT/325P2/396XT/PRO668/PSR800/PRO652
 

troymail

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Thanks for the reply.Would you know if the Uniden 436/536 or the new Whistlers will monitor the systems?

Whistler 1080/1088, 1095/1098 and the new TRX models will do DMR as will Uniden's 436/536 - although my 436 doesn't seem to want to receive (at least) the UHF frequencies many DMR systems use all that well without an external antenna.

Only Whistler has announced that they intend to offer NXDN but for the new TRX models only.
 

jmarcel66

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The PSR-800 and the Whistler WS1080 are essentially the same scanner. What is different that prevents the DMR upgrade offered for the WS1080 from being applied to the PSR-800?

Thanks,
John
 

ka3jjz

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I suspect something in the micro-code for the firmware that specifies this is a GRE vs. Whistler radio. Even tho the functionality may be identical, the code might not be... those of us in the coding industry - regardless of the app - know that there's often more than one way to skin a cat... Mike
 
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darunimal

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jmarcel66: I suspect since GRE is out of business nobody is there to pay the bill to DVSI and Motorola for the licencing to add support to the PSR-800 for DMR, Volume Licensing is usually the way it works, no business, no money, no license.
 

troymail

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It's just business... same reason why when NXDN comes along, it won't be offered on the WS-10xx models... you'll have to buy a TRX-x. They aren't in the firmware business - they are in the business of selling radios.

Research, development, and licensing costs $$$.

Whistler is supporting their products - not legacy products.
 

jmarcel66

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All good points. Can't stay in business if you keep seeing losses; even if it's to be nice. I'd think a charged upgrade for the PSR might work. But even then, it might not be enough to justify.
 

EricCottrell

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Hello,

A fun project has resulted in an unique PSR-800. :)
https://drive.google.com/file/d/0B2DTf80q8MnIZnBqcXFXd0t5QTg/view

The hard part was figuring out how to convert the firmware file so the PSR-800 would accept it. I used the normal method to update the dsp. The battery charging circuit is suppose to be different, but I just disabled it in the configuration. I do not charge batteries in the scanner anyway.

73 Eric
 

EricCottrell

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Hello,

I have not completely tested the PSR-800, so I am not sure everything works. Scan and Limit Search works. Battery charging is a known problem. I can easily flash it back to the correct firmware, but I like being able to create objects on the scanner.

It is highly unlikely that NXDN will be released for the PSR-800, Pro-668, and WS-1080/1088 for the simple reason there is not much flash space left. Flash space in the M16c processor grows down from the top of memory, so firmware for the 512KB flash processor starts in flash memory space that does not exist in the 384KB flash processor used in the PSR-800.

GRE implemented a method that prevents loading the wrong firmware in the scanner by changing the data so it fails the checksum check. You can not directly flash the WS-1080 firmware image into another scanner as the bootloader will incorrectly change the firmware data, the checksum check will fail, and the scanner will end up in firmware update mode. It is not a simple matter of changing only a few bytes.

Another likely reason has to do with later changes to the ECPA. Scanner/Receiver manufacturers got Congress very upset with the easily reversable implementations used to block the 800 MHz cellular range. In some receivers it was just a matter of clipping or adding a diode. GRE had to make sure that the firmware was not easily modifiable, and unblocked versions of firmware could not be loaded (I also have a PSR-600 and there was a Canadian version of the firmware). This maybe the reason the file formats of the programming files EZ-SCAN loads on the scanner are not published, as it could be used as a backdoor to add cellular frequencies.

The firmware file starts with a byte that seems to indicate the platform the firmware is meant for. Just changing the first byte of the file did not work, so it is not likely used by the bootloader to decode the file.
FB PSR-600 BL 1.1
F5 PSR-600 Canadian
F3 PSR-600 BL 1.4
EE PSR-800
E6 WS-1080
E4 PRO-668

The next three bytes are the size of the image. The next two bytes appear to be a checksum and is also where the exclusive-oring of the data starts. The image follows and seems to be a flat binary image starting at the beginning of flash space.

Since I used modified copyrighted programs and tools, I cannot distribute the modified firmware. I would have to write a program from scratch that downloads the WS-1080 firmware, converts it on the fly, and writes it to the other scanners. I am not sure I want the support headaches.

73 Eric
 

Blackswan73

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Since I used to be in FTA satellite, I saw how firmware could be hacked for receivers not intended for it, like the Blackbird clones, for example. Good work. There was some experimentation along this line about a year ago in another thread. Since the radios have the same processor, it follows they should be able to use the same firmware.
 

Joseph11

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EricCottrell, how would one specifically do this if they wanted to for the PRO-668? Any more technical information?
 
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