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Re: How are you testing that new bit of code youve just written?

Hi Guys,
thanks for the replies, John, i own something similar programmer (just probably more expensive todo the same thing) its called a GQ-4X, connects via USB to pc and have used this to write .hex to UV and EE PROMs over the years, it also can be used to program some of the serial flash memory used now on desktop mainboards (this is what i originally purchased it for). what i got annoyed with was 1. not being able to find good EEPROMs around in qty and 2. having to pull them even from a ZIF and program it and slip it back in. although this system works, (or i seem to make more mistakes debugging code then others) the amount of times i would do this over a day, or evening session would get into the 50's, how much time was this wasting? i dont know..

this is why i decided to sit down and build the frankenstein board, old and new tech on it may make some of our more seasoned board builders cringe, but the system is very stable, the "bios" UVprom sits in the first 1K of memory range so thats what the Z80 sees when it wakes up and then i have 1MB minus that 1KB sitting aftrer the UVprom, the UVprom provides the "bootstrap" code to rip off 1MB of data from the Serial Nor Flash device and load it into SRAM at the exact same place (or somewhere else if you like). then later on after a jump to a specific vector (not in 0-1K) it writes to an IO port that permanently makes the chip select of the UVprom high and the lower 1K turns into SRAM and the program copies back all the specific interrupt vector code etc to the <1K range and basic bios code. so the board has a total of 1MB of SRAM on it, which can be put in whatever 1-16MB range on the S100 bus. when it comes to programming the Serial NOR Flash device, i has an onboard programmer that connects to a PC (x86 or x64) via USB that runs some software and the whole erase and programming process of a new 1MB image gets done in about 5seconds. no pulling anything out.. only a board reset to check your new code.