The Sinclair QL Forum

t0nyt wrote: Fri May 09, 2025 9:03 am My first attempt won't look quite like that as I'll be using sockets (as it doesn't need to fit inside the QL and means I can easily extract IC's for troubleshooting) and I'm skipping the upper 16kb to keep it as simple as possible for now so no jumper for that

That all assumes I can put it all together in the first place!

Be aware about the height.
Perhaps with sockets your case won't close. Maybe using very low profile sockets... but really I keep some doubts it would fit inside the case.

Avoiding soldering jumpers till it they are necessary is a pretty good idea.

Popopo wrote: Fri May 09, 2025 9:07 am Be aware about the height.
Perhaps with sockets your case won't close. Maybe using very low profile sockets... but really I keep some doubts it would fit inside the case.

Avoiding soldering jumpers till it they are necessary is a pretty good idea.

Thanks, but the first board I do won’t be going inside a QL, so height isn’t an issue

t0nyt wrote: Fri May 09, 2025 9:15 am Thanks, but the first board I do won’t be going inside a QL, so height isn’t an issue

t0nyt,
What does it gives? Clock signal (RTC), ROM, and what other feature?
I²C ? ... how do you use it?

Thanks

Popopo wrote: Fri May 09, 2025 9:29 am

t0nyt wrote: Fri May 09, 2025 9:15 am Thanks, but the first board I do won’t be going inside a QL, so height isn’t an issue

t0nyt,
What does it gives? Clock signal (RTC), ROM, and what other feature?
I²C ? ... how do you use it?

Thanks

It all new to me! But as I understand it

a) Minerva ROM
b) RTC
c) Minerva also uses battery backed memory to set various boot options (see mk2 manual)
d) I2c

I was experimenting with I2c with my BBC Model B before I put it in storage, so my main interest in this MK2 is the I2c to continue my experiments (and myi2c harnesses all use 15 pin plugs so I can maintain compatibility with the BBC I2c)

t0nyt wrote: Fri May 09, 2025 9:54 am It all new to me! But as I understand it

a) Minerva ROM
b) RTC
c) Minerva also uses battery backed memory to set various boot options (see mk2 manual)
d) I2c

I was experimenting with I2c with my BBC Model B before I put it in storage, so my main interest in this MK2 is the I2c to continue my experiments (and myi2c harnesses all use 15 pin plugs so I can maintain compatibility with the BBC I2c)

Thank you
I will study the circuit then.
Looks very handful

Hi Popopo ,

image gives tOnyt an idea of how his project should look when finished.

The socketed version won't fit the bbql as it is too high.

The 2 pin header is indeed used for a modification which is not implemented on the board .

The remaining parts arrived in the post today, so just got to find time now to give the first board a go (hopefully this weekend)

techy wrote: Fri May 09, 2025 12:12 pm The socketed version won't fit the bbql as it is too high.

Thanks techy,
BBQL, what does it mean? is it what others call stock QL?

Popopo wrote: Fri May 09, 2025 1:06 pm

techy wrote: Fri May 09, 2025 12:12 pm The socketed version won't fit the bbql as it is too high.

Thanks techy,
BBQL, what does it mean? is it what others call stock QL?

Expand it to "black box" or "bare bone", if you like. Yes, stock QL.

or "the real thing"