40 Best Machine Code Routines for the ZX Spectrum - 2nd Ed

[PeterJ]

Found via Facebook

[Jbizzel]

£12 for the paperback. That seems decent.

[Dr beep]

How do you define the 40 best machinecode routines?

I have a 5 byte routine which is used in several emulators to find an opcode in shortest time.

[Bubu]

Just 5 bytes? May I have a look?

[Dr beep]

Just 5 bytes? May I have a look?

DE=PC in this code

LD A,(DE) ; get opcode
LD L,A ; set lowbyte jumppointer
LD H,B ; fixed value to a highbyte table
LD H,(HL) ; get highbyte jumppointer from table
JP (HL) ; go to your opcode routine

table at #XX00
db i00 / 256
db i01 / 256 ; table of 256 pointers

code at #XX00+ 256
i00 do something in the bytes needed ie 4
i04 next code etc....
fill program with all routines


This is how SP2X81 is coded and de GAlaksija-emulator on the SAM

[PeterJ]

How do you define the 40 best machinecode routines?

It's a reprint of this book from 1983: Probably you may not be the intended audience.

https://spectrumcomputing.co.uk/entry/2 ... X_Spectrum

[Dr beep]

It's a reprint of this book from 1983: Probably you may not be the intended audience.

https://spectrumcomputing.co.uk/entry/2 ... X_Spectrum

Indeed, I know enough of Z80 that these routine are familiar for me by heart.

[uglifruit]

Be interesting to see what the updated/additional material in there is.

[merman]

It's a reprint of this book from 1983: Probably you may not be the intended audience.

https://spectrumcomputing.co.uk/entry/2 ... X_Spectrum

It’s more than just a reprint - Jim Bagley is writing new material.

[PeterJ]

It’s more than just a reprint - Jim Bagley is writing new material.

Indeed, you are quite right. Are you clear about how much will be new? I couldn't get that from the Kickstarter page.

[merman]

Indeed, you are quite right. Are you clear about how much will be new? I couldn't get that from the Kickstarter page.

From reading the Kickstarter page again, there are new introductions from the original authors plus new material from Jim Bagley - looks like Jim will be writing new routines/code as well as talking about the Next.

[PeterJ]

looks like Jim will be writing new routines/code as well as talking about the Next.

Excellent! Backed.

[Nitrowing]

www.kickstarter.com/projects/robhwson/2 ... um-reprint

[Mad Fritz]

Excellent! Backed.

Me too

[drdivago]

Same here

[Morkin]

My copy is a bit tatty. It also contains an 'erratum' sheet. That probably drove someone mad in 1983...

[PeterJ]

It also contains an 'erratum' sheet.

Please would you be able to scan that?

[flatduckrecords]

Seems the going rate for a 2nd hand copy is about £40. (Mutant Caterpillar has one if you fancy it!) so £12 for the reprint sounds like a bargain.

I actually thought that price was *just* for the PDF so I’m glad I looked again, thanks for pointing that out @Jbizzel.

[Jbizzel]

Seems the going rate for a 2nd hand copy is about £40. (Mutant Caterpillar has one if you fancy it!) so £12 for the reprint sounds like a bargain.

I actually thought that price was *just* for the PDF so I’m glad I looked again, thanks for pointing that out @Jbizzel.

No problem. I think that's good value..if you printed a pdf copy it would probably cost the same or more.

I'm not familiar with the book, is it worth a punt?

[PeterJ]

I'm not familiar with the book, is it worth a punt?

There's a PDF of the original book in the archive if you want to take a look.

https://spectrumcomputing.co.uk/entry/2 ... X_Spectrum