zippy - yet another serial fastloader

[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

[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

[ops]

Great work! I'll take a better look after summer vacation.

[AndyH]

Nice one!

[DarwinNE]

Very interesting!

[nbla000]

Very good work, I will test it.

[nbla000]

Source, as usual, is also available here

https://eden.mose.org.uk/gitweb/?p=zippy.git;a=summary

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

OPT_PRINT_ADDR
OPT_BANNER

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

[srowe]

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

OPT_PRINT_ADDR
OPT_BANNER

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]

[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.

[srowe]

I look forward to seeing how your tests work out. My pi is too old so I don't have a pi1541.

[nbla000]

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.

[srowe]

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

[nbla000]

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.

[JonBrawn]

I'm having a bit of difficulty with this - I assume that the usage is:

Code: Select all

LOAD"ZIPPY-NTSC.PRG",8,1
SYS1024

However, I'm not seeing any difference in load times. What am I missing?

[srowe]

However, I'm not seeing any difference in load times. What am I missing?

What device are you loading from?