The Sinclair QL Forum

In other words, the QL relies on the sending devices to listen to and react properly to their handshake input lines. If the sending device has no handshake provision, only one serial port can be used for input. The hardware in the QL itself does not 'mask' the serial line input from a misbehaving se...

Nasta - thank you for such a full explanation! So, in summary, HC family can sink the current needed and fast enough from DS to disable the 8301's DSMC - the transistor approach wasn't necessarily just because the decoding through a couple of ICs wasn't fast enough... To this day, I still remember ...

stevepoole wrote:Hi,
I upgraded to SGC and Romdisk and have never had any problems with either.
steve.

How is that relevant to this thread?

Hi guys I have a question regarding the driving of the DSMC(l) line - haven't we always been told that a 'fast switching transistor' should be used to drive this line, rather than TTL logic - something about either the latency or else the OC output? It would certainly simplify things if I didn't ha...

Don't bother with ASL. The QL does not use it and neither should any peripherals except maybe a set of bus buffers. 74HCT125 could gave been replaced by small schottky diodes appropriately oriented (something ike BAT42). HC(T) can be loaded quite a bit in real world applications. Also /WR and /OE on...

Of course - go right ahead

https://groups.yahoo.com/neo/groups/QLHARDWARE/info

As I am the owner of the group, I can pull all the files and send them to someone who can put them somewhere more public - I'm open to suggestions.

PLD sources are available on the yahoo group and have been public for years.

prime wrote:Cheers Mark,

That's exactly what i needed.
Looking at that, the machine cycle of the IPC is 1/ (11MHz/3) = 272ns.

Careful with that. The 8048 clock is divided by 3 from the crystal, but each cycle takes 4 clocks, so it's effectively 11MHz/12

tofro wrote:

Dave wrote: What I want to know is.... Who is Dawn?

She's living under my Gold card.

IIRC girlfriend of the guy who worked with Stuart Honeyball and designed both the GC and SGC PCBs, whose name escapes me...