The Sinclair QL Forum

martyn_hill wrote:If we do go for a uC to attach such things as a keyboard matrix, I'd be happy to develop the uC code.

Sounds great, just in case I was not clear: That is a Q68 issue.
A SGC successor that plugs into the QL extension bus would not need it.

However, a Q68 inside QL case, made possible by such an adaptor, would bring up the question whether a SGC successor is still needed.

martyn_hill wrote:We could go with an I2C connection or else map some SRAM - perhaps dualported - and develop a protocol between the mainboard and the uC (I've been thinking about this for a while) to connect the two.

A conversion to PS/2 would be my favorite, because it requires zero change in SMSQ/E. As a side effect, it would allow a QL keyboard on a PC or (by cheap USB converter) RaspberryPi.

Peter

Hi,

Peter wrote:Is a SGC successor for the original QL case still important to keep the QL scene alive?
Or do the Tetroid (S)GC clones and the Q68 already cover most needs?

The Q68 fulfills my needs and I can use SMSQ/E in Mode 4 @ 1024 x 768 on a modern monitor.

I have QLs with Super/Gold Card, Gold Card Clone, but have to use an adapter RGB to VGA adapter but only at 512X256.

I would like the capability to use my QLs on a VGA monitor with high resolution mode on a modern monitor.

Re: Q68 speed vs 68030 speed

Peter wrote:Yes, would be very interesting! Thank you!

Hi Peter and all,

I have benchmark the Q68 (SRAM area) with a 68030 @ 56mhz (not 50mhz as I first thought) The results are surprising!

The benchmark program is pure 68000 machine code. It is a routine that compute the number of prime numbers smaller than the input value. It is not the fastest algorithm by far but it uses no memory, everything is computed using the D0 to D7 68000 registers. It is however much faster than checking all numbers for primality! The program is 210 bytes long so fits without problem in the SRAM area of the Q68. I can supply the code/listing if anyone wants to do more tests.

This is slightly OT so please feel free to start another thread if you wish to comment.

Here are the results. Again all computers use the same base 68000 assembly code. All QL based computers were running SMSQ\E. The Q68 and SGC (Aurora) where displaying a normal mode 4, 512x256 display.

For an input value of 2000000

Gold Card:
Processor: 68000 @ 16 Mhz
Time: 660 secs

SuperGoldCard
Processor: 68020 @ 24 Mhz
Time: 189,9 secs

Q68 (normal ram)
Processor: FPGA 40? Mhz
Time: 136,4 secs

Q68 (static RAM)
Processor: FPGA 40? Mhz
Time: 47.8 secs

Amiga 1200 (with accelerator board)
Processor: 68030, 56 Mhz
Time: 71,0 secs

NeXT Station Turbo
Processor 68040, 33Mhz
Time: 66.7 secs

*************** The Q68 beats them all !!! ******************

The 68030 processor in the Amiga is no slouch. Here are the specification of the accelerator card for those who can understand such things as burst timing (source: big book of amiga hardware)

Individual Computers ACA-1230 introduced in 2010

CPU: 68EC030 @ 28MHz or 68030 @ 42 / 56 MHz, PGA
all processors are slightly overclocked to allow for a synchronous board design, the nominal speeds are 25 / 40 / 50 MHz
no FPU option
very fast burst timings: 2-1-1-1 (28 MHz), 3-1-1-1 (42 / 56 MHz) memory
64 MB SD-RAM, soldered to the board

memory clock: 56 MHz for 28/56 MHz versions, 42 MHz for 42 MHz CPU

the first processor card to feature a -1-1-1 burst synchronous design
no FPU option as this would have caused too much load on the data bus and would have increased burst timing


François

Hi François,

thanks for the interesting result. I think another topic "Q68 speed vs 68030 speed" makes sense.
Since you are the one who performed the test, it seems better if you also start the topic. Maybe just copy the same message, or move it over, if the forum tools allow that.

Peter

Peter wrote:Hi François,

thanks for the interesting result. I think another topic "Q68 speed vs 68030 speed" makes sense.
Since you are the one who performed the test, it seems better if you also start the topic. Maybe just copy the same message, or move it over, if the forum tools allow that.

Peter

New thread created.

François

Peter wrote:

dilwyn wrote:I think Tetroid's SGC compatible suffers from availability of a critical chip used, so a SGC successor actually makes sense if Tetroid is unable to make more than a few of these add-ons because of that chip shortage.

I think it is absolutely vital though, that whatever add-on card of this type is made, that the improved video connection is included.

This leads to an idea that I didn't have before: Tetroid might be interested in replacing that obsolete chip - maybe an opportunity to add video to his SGC clone?
Tetroid is doing an excellent job, and his recent board seems more like a new design than just a copy.
I would hesitate to bring in "competition", if the video issue can be solved this way.

Tetroid, if you read this, please comment.

I am sorry about the delay with anwswer.
I am sorry, I cant find the original NORMAL old date code EP1810.
I tryed to buy several EP1810 parts - all parts from China / Taiwan is fake - refurbished ( remarked from new date code ) or programmed. I have no chance to find the guaranteed original non programmed old date code EP1810.
I think is possible on USA only , but I have no access to US warehouses.

Hi Tetroid,

thanks for your comments. Do you think it would be realistic to replace the PLD by a new one like the Lattice LC4128 or LC4256?

Peter

tetroid wrote:I think is possible on USA only , but I have no access to US warehouses.

I am based in the US. If I can find or order parts for you on your behalf, let me know.

Peter wrote:Hi Tetroid,

thanks for your comments. Do you think it would be realistic to replace the PLD by a new one like the Lattice LC4128 or LC4256?

Peter

Yes, I think this is possible.

Dave wrote:

tetroid wrote:I think is possible on USA only , but I have no access to US warehouses.

I am based in the US. If I can find or order parts for you on your behalf, let me know.

Thank you , Dave.
I would be grateful if this happened.
I need EP1810LC-20(T) or LC-25(T) , date code from 1990 to 1995.