| ??? 02/10/07 00:36 Read: times |
#132446 - Reality vs perception Responding to: ???'s previous message |
Mike Stegmaier said:
FPGA software will allow you to specify a given output for a given input and will simplify the logic for you. List some. I would like to download and try it. Google 'FPGA software' or simply go to www.xilinx.com or www.altera.com. You can even use these tools to design your own processor. Here's a suggestion :- since you have most of the stuff you need, build a eeprom programmer. As I have said on this site about 5 times, I do NOT want to make a separate programmer, because then I have to remove the rom everytime I change the code, and the chances of me changing code are high. That way you can load bootloader code into your eeprom with ease. Now that is just going to complicate things. (2 eeproms?) Who mentioned 2 eeproms? The complication is in your mind. You only need one eeprom. If all hell breaks loose and you loose the bootloader, you'll have to remove the eeprom chip, put it into your eeprom programmer, reprogram and put it back. This is Exactly what I dont want. Of course - hell has to break loose for this to happen. Basically, to do this would be a rare occurance. I've got over 500 boards out there that work this way, and rarely do I have an issue. What I want happening under the worst case scenario is for the system to allow programming, even if all the eeproms were not programmed or even not inserted. I do not want to depend on an EEPROM for programming operations. Good luck - you'll need some form of persistant storage. EEprom would work for me (I actually use a flash chip). Program the bootloader once, and you can download new code to your heart's content. Mike, I think your perception of reality is distorted. You need to remove the blinkers you're wearing as it is standing in the way of a reasonable solution. You're not flexible as you'd like to have us believe, you're just plain stubborn in the face of overwhelming evidence. You've had the guidance of half a dozen engineers all with extensive experience but yet you see fit to argue - usually because you're not allowing yourself to understand what we're telling you. If one of us tells you something that is plainly wrong - one of the others will point it out. As pointed out above, using a programmer to load an eeprom (or eprom or flash) with bootloader code that stays resident in the device and allows you to download new code at your command complies with your requirements - 1/not having to remove the chip each time 2/being able to download new code You wont have to do a bunch of logic minimisation, you won't have to use a stack of ttl buffers, gate clocks etc. I could even post some bootloader code that downloads via the serial port using XMODEM protocol into a flash device. A few changes and it would work with your eeprom. But you'd probably argue with me that it couldn't work, that there's encryption etc - all because you haven't taken the time to understand it. |
