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My 8Gb Tetroid big girl ?

Posted: Tue May 21, 2019 9:02 am
by polka
Hi all !

Not sure I put this in the right sub-forum !?

Since I got my Tetroïd card, I play again with my faithful old QLs (a JM and a JS) - no longer with my PC emulations.

After trying several different partitionning schemes of the 8Gb CF that went with it, I think that because of the limited RAM space (only 896Kb), some constraints must be considered :
- not too big partitions
- not too big blocksize
- anyway, not more than 32 partitions are allowed on one CF
- not more than 2 partitions should reasonnably be linked-mounted at the same time
Otherwise I noticed, the QL sometimes says "not enough memory", or freezes without saying anything, or slows down a lot.

In the meanwhile, I decided to do tests with a 1Gb and & two 512Mb CF that I had, and finally found out what should work well :
- on the 512Mb CF : 12 partitions of 40Mb with 2Kb blocksize => 80Kb FAT (RAM resident when linked/mounted).
- on the 1Gb Cf : 24 partitions of 40Mb with 2Kb blocksizeb => 80Kb FAT (RAM resident when linked/mounted).
I used the 1Gb CF for a long while with this partitionning, and am globally satisfied with it.

Now, to cope with my 8Gb CF, I had the following idea :
Init the first 1Gb with 24 40Mb/2Kb partitions like on my 1Gb CF, and the remaining 7Gb with 7 1Gb/32Kb partitions, to be used only for direct raw access (PUT/GET/POS or rather, the documented assembler TRAP#3 equivalents) from and to the 32Kb video RAM. Could I hope it will be fast enough for "kinematographic" animations ? I don't know but this is my project !

However, I have things to ponder (or to experiment) : I guess that I will first have to link/mount one of the seven 1Gb partition as a device (say WIN3), this could be done with a SuperBasic command. Then, as I intend to PUT/GET directly the QL 32Kb video ram from a FORTH job, I will have to code (with the FORTH assembler) GET/PUT/POS words through the documented trap#3 calls. But before that, FORTH has to open a "channel" for his job with the special file name "WIN3_*W8d". This may be problematic with the ComputerOne FORTH support for files : because it let only define standard file access control blocks with 128 bytes buffer - inside the 64Kb memory space of FORTH. Thus I may have to define instead a special OPEN for this channel with a TRAP#2-$1 call.

Your opinion ?

P.S. why is this subject about "big" "girl" ? because I use to name the first partition of my CFs "GIRL" (automaticaly mounted as WIN1 at boot) and the others "BOYs" "CATs" "DOGs" and "COWs", mounting them as WIN2 at will with a procedure PET(n).