Sergey Kiselev
Sergey Kiselev
74LS245 is slower than 74AHCT245, but otherwise they should be compatible for the purpose of buffering the data bus. Still there's a slight chance that the part being too fast...
It appears that the issue was related to a hardware issues. Closing...
@nekochan777 display select switch must be checked before display initialization. Especially for MDA/CGA displays. So KBC needs to be initialized earlier. It does make sense not to halt in this...
> I wonder if it can be "faster"? in old 0.9.4 it inits display very fast, while latest version added ~20 seconds of delay without any display with Post Code...
Thank you for your research and the fix!
I've added the following note to the [Assembly Instructions](https://github.com/skiselev/Z80-512K/blob/main/Assembly_Instructions.md): *Note:* The Z80-512K can generate NMI interrupts to the CPU when power failure is detected. The RV1 trimmer resistor is used...
/RESIN has a pull-up resistor (RR2). I don't think CLEAR/RESET should have one. It could be a good idea to connect a diode between /RESIN and VCC to discharge it...
It makes sense. It also should support 29F020/39SF020 ICs in this case. By the way, do you mind contributing the flash programming code changes to the https://github.com/skiselev/8088_bios project?
> Hi, I ordered a "SST39SF020A-70-4C-PHE-ND" instead of SST39SF010A as it is backorder in Digikey. I thought that I can just ground PIN30 and use it. Would I need to...
The SST PH29EE010 should work. Intel 28F001 is not a good choice, as it requires 12Vpp. Please try it with SST PH29EE010, and report back :)