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zippy - yet another serial fastloader
Posted: Sun Jul 17, 2022 12:56 am
by srowe
I've long been fascinated that JiffyDOS implemented an improved protocol to speed up transfers between the VIC and disk drives. Searching the 'net for information was frustrating, there's very little detail.
From what I could find, and from looking at the source for SJ20, I've written the controller code for the VIC-20 from scratch. I'm pleased I've managed to make something small (less than 800 bytes for the simplest usecase) and fast (more than 15x faster to an SD2IEC).
While I've extensively tested it (including an 18 hour save/load torture test) please consider this still experimental. Feedback, comments, bugs are welcome.
Source, as usual, is also available here
https://eden.mose.org.uk/gitweb/?p=zippy.git;a=summary
Re: zippy - yet another serial fastloader
Posted: Sun Jul 17, 2022 7:15 am
by orion70
Wow! Too bad I'm on a vacation now, will try once back home. It'll come particularly useful for long loading times of games for the expanded machine
Re: zippy - yet another serial fastloader
Posted: Mon Jul 18, 2022 2:50 am
by ops
Great work! I'll take a better look after summer vacation.
Re: zippy - yet another serial fastloader
Posted: Tue Jul 19, 2022 3:07 am
by AndyH
Nice one!
Re: zippy - yet another serial fastloader
Posted: Tue Jul 19, 2022 3:45 am
by DarwinNE
Very interesting!
Re: zippy - yet another serial fastloader
Posted: Wed Aug 03, 2022 9:39 am
by nbla000
Very good work, I will test it.
Re: zippy - yet another serial fastloader
Posted: Fri Aug 05, 2022 9:13 am
by nbla000
I'm playing a bit with it by compiling from Windows 10 (not makefile), it seems that I'm not able to use these options:
Code: Select all
dasm zippy.asm -DOPT_SAVE -DOPT_API -DOPT_CART_SA -DOPT_PRINT_ADDR -DOPT_BANNER -DSYS_PAL -ozippy-pal-full.prg
--- Unresolved Symbol List
print_cr 0000 ???? (R )
chrout 0000 ???? (R )
print_to_addr 0000 ???? (R )
print_from_addr 0000 ???? (R )
--- 4 Unresolved Symbols
While this command works:
Code: Select all
dasm zippy.asm -DOPT_SAVE -DOPT_API -DOPT_CART_SA -DSYS_PAL -ozippy-pal-full.prg
maybe something is missing on kernal-defs.asm and/or other files.
In addition, it could be useful to add another option like START_ADR to compile for a custom start address instead of $400:
It requires just a small update on zippy.asm:
Code: Select all
ifconst START_ADR
org START_ADR
else
org $400
endif
Re: zippy - yet another serial fastloader
Posted: Fri Aug 05, 2022 10:30 am
by srowe
nbla000 wrote: ↑Fri Aug 05, 2022 9:13 am
I'm playing a bit with it by compiling from Windows 10 (not makefile), it seems that I'm not able to use these options:
Code: Select all
dasm zippy.asm -DOPT_SAVE -DOPT_API -DOPT_CART_SA -DOPT_PRINT_ADDR -DOPT_BANNER -DSYS_PAL -ozippy-pal-full.prg
--- Unresolved Symbol List
print_cr 0000 ???? (R )
chrout 0000 ???? (R )
print_to_addr 0000 ???? (R )
print_from_addr 0000 ???? (R )
--- 4 Unresolved Symbols
I should have been clearer in the instructions, if you enable these options you have to supply the
print_ functions yourself.
chrout could probably be included in the KERNAL symbols.
In addition, it could be useful to add another option like START_ADR to compile for a custom start address instead of $400:
That's a good idea, I'll add that shortly. The top-level file is intended only as a example, I include the main source files when I'm using it IRL.
[Edit: I've pushed a v1.2 with these changes]
Re: zippy - yet another serial fastloader
Posted: Sat Aug 06, 2022 1:55 am
by nbla000
thanks for your explaination, I'm planning to test it in both PAL and NTSC machines, I wish to compare it with SJLOAD and test compatibility with pi1541 (both 1541 and 1581 emulation in JiffyDOS mode)
I will report you results.
Re: zippy - yet another serial fastloader
Posted: Sat Aug 06, 2022 2:29 am
by srowe
I look forward to seeing how your tests work out. My pi is too old so I don't have a pi1541.
Re: zippy - yet another serial fastloader
Posted: Mon Aug 08, 2022 4:26 am
by nbla000
srowe wrote: ↑Sat Aug 06, 2022 2:29 am
I look forward to seeing how your tests work out. My pi is too old so I don't have a pi1541.
I've successfully tested the NTSC version with pi1541 (both 1541 and 1581 emulation), I've also compared speed with SJLOAD and JIFFYDOS and they are quite similar, while by using an SD2IEC device, Zippy it's slighty faster but quite similar to SJLOAD, by using a 95 BLK file it requires about 4 seconds with both Zippy and SJLOAD and 5 seconds by using JiffyDOS.
Anyway It is a bit smaller that the minimal SJLOAD version and could be useful in some situations, very good work!
PS: I have no PAL machines at the moment (they are on recapping phase) but if you need, I will test Zippy+pi1541 on PAL machines when possible.
Re: zippy - yet another serial fastloader
Posted: Mon Aug 08, 2022 10:46 am
by srowe
nbla000 wrote: ↑Mon Aug 08, 2022 4:26 am
I've successfully tested the NTSC version with pi1541 (both 1541 and 1581 emulation), I've also compared speed with SJLOAD and JIFFYDOS and they are quite similar, while by using an SD2IEC device, Zippy it's slighty faster but quite similar to SJLOAD, by using a 95 BLK file it requires about 4 seconds with both Zippy and SJLOAD and 5 seconds by using JiffyDOS.
Anyway It is a bit smaller that the minimal SJLOAD version and could be useful in some situations, very good work!
Thanks for confirming this, I only did limited testing of the NTSC version with VICE (and, obviously, that didn't test an SD2IEC). The size reduction was a combination of general optimizations and making the load routine use a common function for byte and sector modes. That required some ugly stack manipulation, I might go back and see if I can find a neater solution.
PS: I have no PAL machines at the moment (they are on recapping phase) but if you need, I will test Zippy+pi1541 on PAL machines when possible.
Most of my testing was of the PAL version with a mixture of VICE and my FE3. When you are able a check of pi1541 and PAL would be nice,
Simon
Re: zippy - yet another serial fastloader
Posted: Tue Aug 09, 2022 1:23 am
by nbla000
srowe wrote: ↑Mon Aug 08, 2022 10:46 am
PS: I have no PAL machines at the moment (they are on recapping phase) but if you need, I will test Zippy+pi1541 on PAL machines when possible.
Most of my testing was of the PAL version with a mixture of VICE and my FE3. When you are able a check of pi1541 and PAL would be nice,
I forgot to mention that I've tested it also with a generic 32k expansion by compiling for $B000 address and with Mega-Cart by compiling for IO2 address by overwriting Mega-Cart music data just for tests, It's a pleasure to play DOOM with SJLOAD/Zippy, I forgot FE3 but I will test it too with my NTSC machine.
For PAL machines you have to wait a bit since now in Italy there is an holiday period and the repair man who is recapping my VICs is closed for a while.
Re: zippy - yet another serial fastloader
Posted: Sun Jun 18, 2023 12:29 pm
by JonBrawn
I'm having a bit of difficulty with this - I assume that the usage is:
However, I'm not seeing any difference in load times. What am I missing?
Re: zippy - yet another serial fastloader
Posted: Sun Jun 18, 2023 1:40 pm
by srowe
JonBrawn wrote: ↑Sun Jun 18, 2023 12:29 pm
However, I'm not seeing any difference in load times. What am I missing?
What device are you loading from?