I don't have any pressing need for it at the moment, but I can see how useful that would be! That's one less barrier to someone who wants to start hardware hacking on the ROM socket. How much are you expecting this gizmo to cost?
—b9 On Tue, Jul 30, 2024 at 10:23 PM Brian K. White <[email protected]> wrote: > Anyone want one of these? > https://github.com/bkw777/Molex_7880x_bus_tap > > I'm going to make one for myself and I don't mind making a few more > along the way, considering "Anyone" is probably just Steve since it > would mostly just be useful for debugging REX and REX-like things. > > The two parts are connected by an FFC cable and lets you connect a logic > analyzer to the option rom socket while something is in operation in the > socket. > > The cable is thin and you can even install the rom door cover and flip > the machine back over and use normally with the rom hanging out to the > side of the machine. > > What I want it for is, this doesn't work, but I think it's close, maybe. > > https://github.com/bkw777/REX_ATF > > > REX Classic and REX# are based on the Xilinx XCR3064XL CPLD. That part > was EOL'ed last year. > > This Microchip (ATMEL) ATF1504ASL is a very similar chip, and is still > being made and sold new. > > Extra bonus, it's a fully native 5v part, so there is no 3V3 regulator > needed and only one VCC rail to route which makes the pcb simpler. > > And I managed to reassign some pins so the jtag pins are not used for > general i/o, so programming is a lot simpler. No more aux power > connection, power cmes from the programmer, no more PORT_EN jumper and > pulldown resistor, just connect the jtag and go. > > -- > bkw >
