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builderpages:plasmo:spx-mpu [2017/08/06 13:29] plasmo |
builderpages:plasmo:spx-mpu [2017/10/10 11:41] (current) plasmo |
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ADC Communication' | ADC Communication' | ||
- | —photo | + | [[https:// |
SPX-MPU contains: | SPX-MPU contains: | ||
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Perhaps there is a way to upload software patch into the board, but I have no knowledge of it. In the absence of software upload, the most obvious way of changing software is to replace the boot flash with a new set of boot flash. The boot flash are located on the corner of the board above the DB25 connector. UB2 is the most significant byte and UB3 is the least significant byte. For people with the appropriate skill and equipment, UB2 and UB3 can be readily cut out and sockets installed in their place. New boot software can be programmed in an external flash programmer and installed in the sockets. The board will now boot up with the new software. The drawback with this method is that every board repurposed need to remove two flash chips, install two sockets and program two new flash chips. That's a significant effort in time and money. There is another way: | Perhaps there is a way to upload software patch into the board, but I have no knowledge of it. In the absence of software upload, the most obvious way of changing software is to replace the boot flash with a new set of boot flash. The boot flash are located on the corner of the board above the DB25 connector. UB2 is the most significant byte and UB3 is the least significant byte. For people with the appropriate skill and equipment, UB2 and UB3 can be readily cut out and sockets installed in their place. New boot software can be programmed in an external flash programmer and installed in the sockets. The board will now boot up with the new software. The drawback with this method is that every board repurposed need to remove two flash chips, install two sockets and program two new flash chips. That's a significant effort in time and money. There is another way: | ||
- | —-photo of the board with sockets | + | [[https:// |
- | **Reprogramming | + | **Programming |
- | The reprogramming | + | The programming |
- | —–Photo of reprogramming | + | [[https:// |
- | The software works as follow: switch the boot chip select to the reprogramming headers and power up. MC68302 will execute the new boot software located on the reprogramming headers. Load a cloning software into the 68302SBC RAM and execute it. This cloning software will copy the boot software located on the reprogramming header into RAM and then examine the device ID of the flash continuously and wait for the switch to connect to the original boot flash. Once the switch to the original boot flash is made, the cloning software will erase the flash and copy the new boot software into the original boot flash. The repurpose of the board is now completed. This method still requires some soldering/ | + | [[https://www.retrobrewcomputers.org/ |
- | —photo | + | Photo of programming headers removed |
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+ | [[https:// | ||
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+ | Detailed view of the programming header installed over the existing boot flash | ||
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+ | Yet another way of replacing the original boot software is to program a set of flash with the desired boot software, straighten the ' | ||
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+ | [[https:// | ||
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+ | Photo of custom boot flash ' | ||
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+ | [[https:// | ||
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+ | Detailed view of the ' | ||
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+ | ---- | ||
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+ | The software for the programming headers works as follow: switch the boot chip select to the programming headers and power up. MC68302 will execute the new boot software located on the programming headers. Load a cloning software into the 68302SBC RAM and execute it. This cloning software will copy the boot software located on the programming | ||
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+ | This method still requires some soldering/ | ||
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+ | * The smt capacitor between UB2 and UB3 needs to be removed, otherwise the headers will not fit properly | ||
+ | * The 330 ohm resistor connecting boot chip select need to be removed and a pull up resistor | ||
New boot source code, S-record | New boot source code, S-record | ||
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ADC SPX-MPU [[: | ADC SPX-MPU [[: | ||
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+ | ADC SPX-MPU [[: | ||
Photo [[: | Photo [[: |