General Stuff(tm)

[stephen_usher]

Looks like I'll be adopting another machine soon... A Mega2 ST inc. UK keyboard.

[PhilC]

Looks like I'll be adopting another machine soon... A Mega2 ST inc. UK keyboard.

Nice, I must get round to fixing the temperamental floppy drive on mine.

[rubber_jonnie]

Looks like I'll be adopting another machine soon... A Mega2 ST inc. UK keyboard.

Oooh, nice

[stephen_usher]

OK... Fixed the cable but... the pin-out I have is still very wrong. After buzzing out the Sony VGA adapter it looks like the pinout I have has pins 4 and 5 swapped... i.e. it has SENSE0 on pin 4 and GRN.VID on pin 5 but the Sony adapter has the opposite. *sigh*

I think I'm going to have to cut some tracks and add some bodge wires. At least I can do this with the new PCB.

[rubber_jonnie]

OK... Fixed the cable but... the pin-out I have is still very wrong. After buzzing out the Sony VGA adapter it looks like the pinout I have has pins 4 and 5 swapped... i.e. it has SENSE0 on pin 4 and GRN.VID on pin 5 but the Sony adapter has the opposite. *sigh*

I think I'm going to have to cut some tracks and add some bodge wires. At least I can do this with the new PCB.

How vey annoying

[stephen_usher]

OK, after rewiring those two traces I've got h-sync and v-sync out of the LHM1980, so that's a positive sign. However, I couldn't get the h-sync to go to the VGA connector properly, It's being pulled down by something, so I started probing around the header pins and trying to match them to the pinout I have for the Mac II video port...

Oh dear! It's not just the SENSE0 & GREEN-VID which are swapped. Oh no, there's video on the SENSE1 pin too. The whole bloomin' lot are wrong, and it's not my cable as I've checked that. *sigh*

[rubber_jonnie]

OK, after rewiring those two traces I've got h-sync and v-sync out of the LHM1980, so that's a positive sign. However, I couldn't get the h-sync to go to the VGA connector properly, It's being pulled down by something, so I started probing around the header pins and trying to match them to the pinout I have for the Mac II video port...

Oh dear! It's not just the SENSE0 & GREEN-VID which are swapped. Oh no, there's video on the SENSE1 pin too. The whole bloomin' lot are wrong, and it's not my cable as I've checked that. *sigh*

Sounds like you have a right jumble on your hands!!!

Good luck.

[stephen_usher]

I think that I'll have to buzz out the connections on the Sony Mac->VGA adapter, I can then get the correct pin assignments. Once I have that I can create another cable with the correct wiring and make up another board without my bodges and cut traces. That's if I bother continuing at all.

[rubber_jonnie]

I think that I'll have to buzz out the connections on the Sony Mac->VGA adapter, I can then get the correct pin assignments. Once I have that I can create another cable with the correct wiring and make up another board without my bodges and cut traces. That's if I bother continuing at all.

Not sure if it's the same/similar connector, but I bought a VGA adapter for my Performa that is 15pin to VGA but with dip switches. Unfortunately it's sealed, so I can't tell exactly what the switches do (It's currently set for my Performa) unless I can find the dip-switch layout. I'll see if I can find it if it'll help.

[stephen_usher]

It's more the other wiring, such as the video and sync signals I need.

The DIP switch just changes the connections to the SENSE0->2 pins to tell the Mac what display is connected. For the 640x480 colour display pins 4 and 10 are grounded.