Forgottenmyname - Progress

[exxos]

1 step forward is that i have a stable screen, although its yellow and im back to the 2mhz pulses on /AS and the data lines

Did you do this one as well ?

https://www.exxosforum.co.uk/forum/viewt ... 099#p10098

[PhilC]

that'll be a no, lol

[exxos]

that'll be a no, lol

C'mon keep up

[PhilC]

I just did, it's not pretty,

still getting /AS as 2mhz btw

[exxos]

still getting /AS as 2mhz btw

Just to check you did solder the jumper links up ?

[PhilC]

All 5 yes

[PhilC]

Just looking at the schematic for the ROM, on the Mega and ST A16 is also /OE on the ROMS but on the STF A16 is an individual entity. Should this be tied into /OE as well? I'm getting /OE mostly high on the ROM but with a few small blips once in a while. /OE Being high is Read disabled right?

[exxos]

Just looking at the schematic for the ROM, on the Mega and ST A16 is also /OE on the ROMS but on the STF A16 is an individual entity. Should this be tied into /OE as well? I'm getting /OE mostly high on the ROM but with a few small blips once in a while. /OE Being high is Read disabled right?

OE HI = ROM disabled.

Its how the ROMs are always wired up on my ROM boards and boosters. I don't use any address lines as chip enable lines, I just tie CE to gnd instead and just just OE.

I will have a look on my STFM rom board just to see how that was wired up..

[exxos]

OK so probably the confusion over A16 is 6 ROM vs 2 ROMs. A16 is wired for "2 roms" but of course thats 2x8 bit roms, whereas I use 1x16bit ROM. So A16 is correct. GLUE decodes the ROM address which drives the OE (on the plcc rom) via the LS11.

So its all correct...

[PhilC]

Ok, so all three ROM1,2,3 inputs have to be high to disable the /OE on the ROM. Can you think of any reason that the GLUE is disabling the ROM?

I don't suppose there's some GLUE logic diagram around anywhere is there?