Book Club: Commodore 64 Programmer's Reference Guide

[@8_Bit]

If anyone has other printings of the C64 PRG, it'd be great to know: 1) If the "Commodorf" typo (page 121) was fixed in the 2nd printing (we already know it is by the 3rd printing!) 2) When the Z-80 & CP/M section was blanked out on page 368 and on (it was in the 9th printing, gone for sure by the 15th printing) 3) Are there any other differences between the various first edition printings?

[@Okurka.]

The second printing still has the typo: www.classiccmp.org/cini/pdf/Commodore/C64%20Programmer%27s%20Reference%20Guide.pdf

[@karlramberg]

First edition, fourth printing- 1983. Commodore UK. Biggest difference is that it is bound with metal spiral binding coils, not the plastic binding.

[@jameschamblin7120]

@@karlramberg I think the metal spiral binding has to do with where the book was bound. I have a tenth printing that has the metal spiral binding. @8-Bit Show ANd Tell Tenth printing 1984 still has the Z-80 section.

[@snakefriesia6808]

I have a First Edition , Fourth Printing , UK version , bound in metal rings , and the Commdorf is definitley gone at page 121, the Z-80 /cpm section is still present on pages 368 and on i also have First Edition First print, US version , bound in plastic , typo and z-80 present

[@CommodoreFan_nl]

First Edition -Fourth printing -1983, the Z80 & CP/M part is present. First Edition - Eleventh printing -1984, the Z80 & CP/M part is still present.

[@QuintusCunctator]

This is, no joke, one of the most important books in my life. When I was 4 years old, my father bought a C64 and, bless, this gem was packaged with it. Basically I learnt how to read on it, and the rudiments of English language (I'm not a native speaker) by pestering my parents about the content ("mooom, what does PRINT mean?"). Plus, it kickstarted my career as a programmer. Thanks, Commodore!

[@jack002tuber]

That is so cool! :-D

[@yataman6727]

U were in the right timing for this book to start.. At the times i startet my real job . Without any connection with computers or programming. In school nowere computers. After the last year i came out of highschool with economcs they come for first time . I needed a decade after plus five years to start at 30 . Very late for restarting again.

[@0LoneTech]

I was too late to get a C64, but similarly got my English vocabulary started on the STOS manual. It included some mishaps like the time I thought the funfares.mbk file was corrupt, as I didn't yet understand mbk (for memory bank) files could contain music, not just sprites. And of course I had no clue how things were actually pronounced.

[@brianbirkinbine2054]

The C64 is the reason I chose my career. Loved that book

[@jack002tuber]

I am in IT and have been for 24 years, and got started with computers using the c-64.

[@rancidbeef582]

I started on a TRS-80, but later "upgraded" to a C64. I'm still writing software for a living. While I love Linux and being able to use machines with gigabytes of RAM and terabytes of disk space, nothing quite compares to the feel of those old 8-bit machines. I think the kids today are missing out on the fun stuff.

[@donnierussellii4659]

I asked for this book one year as a Christmas present. It was falling apart after a few years. I learned assembly and wrote a few games. It was so exciting to get that extra speed over BASIC. As a labor of love I made a formatted pdf, suitable for printing.

[@8_Bit]

Did you learn assembly just from this one book? If so, I'm impressed. It's a great reference, but the assembly tutorial section was lacking in my opinion.

[@donnierussellii4659]

I had this book and some Compute books. I used BASSEM. I was pretty determined.

[@weedmanwestvancouverbc9266]

I got this book as a birthday present from an adult who used my PET based BBS in 1983. He also paid for a subscription to Compute! and escorted me and a friend to the Computer Fest at Robson Square as we were both teens. Jim Butterfield was there giving a lecture, and while he was just starting, a remote-controlled robot that was still on stage with them started up for few seconds and moved across the stage towards and then stopped. He said that robot accidents in the future we're probably going to cause a lot of injuries to male virility in the future. I keep wanting to go to one of the local television stations and see if they still have the video of this on file someplace

[@Danny-bd1ch]

I can so relate to this person explaining his confusion to the book. Myself as a 13 year old in 1981, had such trouble understanding the book and its methodology. My grandfather first had a Vic-20, followed by the C64. I spent many hours inputting basic code from magazines for my gaming enjoyment. Only to have to wait for magazine corrections, to get the game to work.

[@SouthwestJoker]

I still have my original Programmer's Reference Guide from 1984. Great video Robin.

[@thewizardmountain]

This book came with the second hand c64 my parents bought me in the 90s. Taught myself to program using it!! Holds a super special place in my heart.

[@Brian-vs9sd]

You had me at deep and nerdy.

[@Polaris64]

Thanks for reviewing this book, your video brought back a lot of memories! I remember using this book exclusively as reference when I built a C64 emulator quite a few years ago before I had reliable Internet access, which just goes to show how much useful information was contained within those pages.

[@donkeytonk]

Wow so many memories. I managed to create some of the demos in this book when I was about 10. Inspired me to make some of my own basic games including a text adventure, a troll-style breakout clone (the physics would do the opposite of what you expected) and a track and field style button mashing racing game. I remember my tape deck breaking on me and I ended up handwriting one of the games in a physical notepad! Had such an interest in pursuing this as a career but my parents and even teachers were clueless when I asked them. Tried to pick up some other reading material but was all beyond my ability. Gave up and instead pursued business related studies. Fast forward 25 years and I decided to take up games programming as a hobby. Just had my first mini hit and given up my day job to do this full time. Better late than never to pursue the dream!

[@bcostin]

I used to carry the PRG around in my bookbag to read during my bus ride to and from school. I'd completely forgotten about that awesome little sprite editor. Being able to edit something visually via the DATA statements and then have a sprite was very satisfying. It was also fun to demonstrate to my parents (who pretended to be fascinated every time).

[@evileyeball]

One of my favorite Professors was a fan of scrunching. He passed away a few years back but I always remember him fondly when I hear things like scrunching.

[@dalestyx]

I still have my original round at my mums house, with various other books too. I never ever managed to write a program in assembly language sadly. Thanks for upping this video, it brought back fond memories of a time when the c64 was at its prime and I was much younger.

[@weedmanwestvancouverbc9266]

Robin, the 10th printing of the 1st Edition STILL had the section on the CP/M cartridge.

[@jack002tuber]

@@weedmanwestvancouverbc9266 I have the 1st edition 5th printing and the CP/M is still in there

[@weedmanwestvancouverbc9266]

@@jack002tuber We kno it was there for Robins edtion #9 and for mine #10

[@michaellosh1851]

Thanks for posting! I still have my original copy (1st ed. 3rd printing). I believe I'm of a similar age and was equally bewildered by sections of that book when I first got it in my youth. Now I wish everything in computers was as straightforward and well-documented!

[@r000tbeer]

Thanks for the trip down memory lane, loved it!

[@rancidbeef582]

You mention taking the book to college... I used to take my "Mapping the 64" and a binder with a disassembly print-out of the kernal and Basic ROMs to my college classes. When I was bored or had some downtime, I'd go through the code writing comments in the margin about what it was doing, using the Mapping book as a guide. I learned a lot about 6502 assembler and an ton about doing various tweaks on the 64. Fun stuff!

[@williammckeever4790]

Always like your references to Zellers. I bought a lot of my c64 games and hardware from them back in the 80's. Wish they were still around!

[@MattKasdorf]

I once bought 5 boxes of Star Raiders for the 2600 just to get the keypads, they were just $2cdn each.

[@JSRFFD2]

My local bookstore carried this book, but my local software store only sold games. Thus, I had this book long before I had an assembler or even monitor! I was therefore baffled when I read about 64mon. My first ML experience was with the Epyx Fastload cart, which could disassemble but not assemble! I didn't really "get" assembly until I ended up typing in a BASIC program for an assembler from a book. I wish I had had better tools earlier! Still, I was happy when I eventually bought the "64 assembler" via mail order, when this all clicked into place. I loved this book! Thanks for the detailed review.

[@8bitgamerC64]

Probably my most used book when i was coding the c64. i remember writing a sprite multiplexor and getting 128 sprites on screen. i had to count how many clock cycles each 6502 instruction took so i wouldnt slow down the CPU (under raster interrupt) too much.

[@MurderMostFowl]

I used the programmers reference guide so much as a kid that I had to tape the cover and first few pages back together so many times. Such great memories.

[@johansenphotography]

I agree with you on the Definitive Guide. I printed and spiral bound my own copy of the for the VIC20 and plan to do so for the C64 too. And you are correct. Whatever the Commodore - nothing can beat the official Programmer's Reference Guides!!

[@mickehog76]

Love that book "programmer's reference guide". Learned a lot about C64 and 6502 assembler. But I had the version with a white front page and didn't used that spiral. C64 was and is still an amazing computer. My personal favorite. So much fun you can have with C64 if you are a programmer.

[@bbartky]

I bought my C64 in June ‘83 and bought the _Programmer’s Reference Guide_ about two weeks later. And yes, my copy had the Z80 section. 😀 I don’t remember if it had the typo or not but it does sound vaguely familiar. That and _Mapping the Commodore 64_ were my “bibles” that kept right next to my C64 at all times. 18:32 I agree 100% about the excellent documentation helping Commodore. I have to admit my bias, however, since I’m a technical writer. 😂 32:56 The balloon! 🥰 I totally forgot about that. And about the date format, while the normal format in the US is month-day-year (e.g., September 1, 2024) there are exceptions. For example, my first job after college was editing reports for the US Air Force. They required us to put time in 24-hour format UTC and dates in day-month-year format. However, I’d say most Americans aren’t familiar with that format so that woman who wrote that dedication probably wasn’t American.

[@larssjodahl7660]

The timing of this is uncanny! I started tinkering with my c64 this spring, and ordered THIS VERY BOOK on eBay 9 WEEKS ago, with eta TOMORROW, and you release this video now? Almost unbelievable. Gonna watch the rest of the video tomorrow, but that you just happen to publish a review of this ancient tome this very weekend, simply must be a sign from the 8bit gods...

[@rohart6981]

I have a First Edition Second Printing 1983 and Commodorf is still in that edition. I really enjoy your book club videos. It also has the Z80 CPM section.

[@darthbukowski6894]

A PDF is fine if you need the guide but there is nothing like having the paper copy in your hands.

[@BillyMartin4Life]

This quote was said for for in relation to when a game company decided to get one of the reference books it used back into print, but I think it can still apply here, lol: "You can't use a PDF to beat the ignorance out of someone" Nicholas Moran AKA "The Chieftain"

[@darthbukowski6894]

ungratefulmetalpansy , no I completely understand that.

[@Asterra2]

Never owned a C64. Definitely the pc/gaming era that I flat out missed out on. Jumped straight from Vic20 to Amiga. But I do remember the books with those plastic spool binds. And how that tended to promote book wear. Vic20 book had one or two specimens of complete (Basic) program. I was quite young back then so it probably shouldn't surprise me that I only successfully typed the whole thing in on like the fifth try over the span of a year. I could tell I'd done it right, because the end result was a lucid, playable space game kind of in the vein of Space Invaders, though the baddie was a giant asteroid (imagination was needed here). I was really too young to take instructions from a book, but I can remember the day I figured out looping and how that was needed to perpetuate motion. If I could have read that in an instruction book, that would have saved me a lot of time.

[@garyhucker8314]

Love your videos. My book is bound on the right side instead of the left. It's first edition, first printing - 1982 but also says second Australian printing - 1984. Has the section re Z80 but no Commodorf typo.

[@rivards1]

Bound on the right? Ya crazy Aussie, it's upside down!

[@stefanocrespi5424]

Thanks for sharing, Robin, this excursus is pure gold.

[@marred2277]

I'll admit, your video style took a little getting used to---Animated Hand teaches 8 bit computing. But I now see it's close to perfect as a way of presenting this information. Together with your voice, it's a great combination that makes your videos very easy and interesting to watch. Your voice and speaking style is very well suited for teaching, and being able to watch you type helps one follow along. Keep up the good work.

[@KayoMichiels]

Neat! I got a First edition, Tenth printing. Loving the in-depth study of the computer.. oh and the wiring diagram at the back.. just wow!

[@steviebboy69]

I have this book among others packed away I should check what revision it is, but from memory the book is mint condition. Years ago I purchased from someone about 4 C64's newer and old style and around 5 1541's and heaps of disks and a few cartridges and books as i mentioned. There were also some datasette tape units and a SX-64. i did get this for around $100 AUD. This was around late 1998, gees i see sx-64 going for crazy amounts on fleabay.

[@jonasrullo2590]

Nice walkthrough. I'm looking forward to the next set. Great song. I was the same way but didn't get to the level of actual game programming. Just a bit of music and BBSing here and there.

[@MurderMostFowl]

I remember reading through the instruction set and being so interesting in learning how many cycles each operation took and being weirdly obsessed with memorizing it all, even before I really understood what it all meant

[@Anth369]

Hey Robyn, just revisiting this old video. I’m glad you mentioned how terrible the book is at explaining machine code. I tried to wrap my head around it in my teens and remember just being absolutely bewildered. I figured I just didn’t understand machine code and gave up. Now, 30 odd years later, I’m back on the mission of coding in machine language. Nice to know it wasn’t just my intellect, but some terrible instructions given! Cheers mate from Melbourne Australia.

[@comchia4306]

18:30 IIRC, Atari's notoriously bad system documentation was a significant factor in the Jaguar's demise, especially since programmers struggled to get the system's full potential unlocked. And, as somebody currently learning a bit about the 6502, this book looks fascinating. Thank you for the video!

[@BertGrink]

Commodorf is a small village in Germany.

[@BertGrink]

@ungratefulmetalpansy Yep

[@waymamma]

Perfect and awesome video Robin, thanks so much for publishing this from your Patreon channel. This is exactly the "nerdy" kind of content I love from your channel!

[@chipacabra]

Probably the closest equivalent for the Atari 8-bits was De Re Atari in 1982. Failing to support developers was always one of Atari's weaknesses, it's true.

[@jack002tuber]

Great video. I have this book, got it when it was new. I wrote in it a lot. It broke the comb that holds the pages, I replaced it with my own invention, I have plastic tabs on the pages like you see on some Bibles. Used it a lot and learned a lot about the commodore and about programming. Mine is first edition, 5th printing (no commodorf typo) This is one of my most loved books ever.

[@HelloKittyFanMan.]

This was nice! Thanks for releasing this to the general public!

[@DaveF.]

Thanks for uploading this to youtube - that was, and still is, one of the favourite computing books I've ever owned. The opcode reference list and the schematic wowed me completely. I've just brought myself a BBC Master system, and the appropriate reference manuals for that and I'm really looking forward to getting into a deep delve of that with it's built in assembler. Thanks!

[@peachgrush]

19:53 The mythical VSP Cartridge appears once again :)

[@MurderMostFowl]

So interesting... especially since VSP means something completely different to the C64 these days!

[@csbruce]

2:47 "1. BASIC PROGRAMMING RULES" can be interpreted in a few different ways. 8:59 Don't the Interrupt-control registers in the CIA operate a little differently for Read and Write? 12:00 It doesn't seem that the 2114 is actually connected to the VIC at the place you indicate, but that some of the Address lines go "under" the 2114. The special parallel connections between the VIC and 2114 would be the Data lines that are also on the system bus. They go to D₈…D₁₁ on the VIC (where the system bus is only eight data bits wide). 12:13 I'm sure Bender from "Futurama" also had "naked" circuits on his dorm wall. 15:18 I wasn't able to understand the same section of the VIC-20 Programmer's Reference Guide. It wasn't until the last class of a mostly-pointless night course on the VIC-20 that everything clicked into place. 17:13 At the bottom of page 109: it's messed up that they didn't make the FRE() function of their new computer with the huge amount of RAM return a positive number. Lots of people probably felt gypped! 19:12 Of if you need LESS detail: The Complete Commodore Inner Space Anthology. Less detail is useful when you already know how the stuff works but just need to remember the memory addresses. 20:34 Did any cartridge ever actually use the Dot-Clock signal? 28:13 PETSCII's control codes grew by accretion from the PET to the C128. Is there really any logic to the codes beyond the 128 bit indicating a Shifted key? 30:08 I once had a letter about VIC-20 memory expansion published in Power/Play. 30:23 I'm partial to The Transactor as well… I think it also started out as a publication owned by Commodore, or Commodore employees. 31:51 The VIC has five DRAM-refresh cycles are in its 63 to 65 memory accesses per scanline, but how does the DRAM get refreshed on the C128 in 2-MHz mode when all of the VIC's accesses are taken away? 34:30 No, you still get gypped - RAM locations $0000 and $0001 are unavailable for programming! It's even worse on the C128, as locations $0000-$0001 and $FF00-$FF04 are unavailable on each internal RAM bank! 38:11 "Ten years old, 1983." With data like this, one could calculate how old you are! 38:16 I had a computer in my room when I was a kid, which made it impossible to be bored! Of course, today, the average household probably has over a hundred computers, if you include every Turing-complete computational element.

[@jack002tuber]

Man, you are more Robin than Robin! :-D

[@8_Bit]

@@jack002tuber I'm out of a job if csbruce ever starts his own channel!

[@sabriath]

I loved that book, I don't think I have it anymore though, it's probably in my attic somewhere if I still have it at all. The book I do keep around though is the "Programming the PET/CBM" by Raeto West, it doesn't have much of the video memory stuff that book had, but it is still good for assembly lookups.

[@dougjohnson4266]

So I had to go check my book. First ed, Third printing and it has the Z-80 info, no ...DORF. :-) Thank you sir.

[@8_Bit]

Hopefully someone with the 2nd printing will resolve the mystery of when DORF was removed :)

[@moshly64]

​@@8_Bit I have First edition Fourth printing 1983 (wire bound, marked Commodore UK on back cover) has Z80 section, DORF has been fixed.

[@opengldirectx1259]

Hi Robin! I was lucky enought to get one of them today for 3Euro! Its fourth printing 1983 and its like brand new! I Found it in Poland 😊 Book is great:)

[@JustWasted3HoursHere]

18:00 I totally agree that getting programming info out there is in the best interest of the manufacturer. Atari and Apple both have a long history of trying to keep this info to themselves or leaking it out bit by bit, but in the end it hurt them. In my opinion, not only should all of these 8 bit systems have readily available programming info, but that info should be included with the system, along with actual programming tools to get started right away! If a system has a large library of programs for it people are more likely to buy it. It's a win/win situation.

[@jeffhyche9839]

The first time I encountered this book was right after I got my first C-64. I dug it out of a $1.00 barrel at a used book store. It looked like it had been run over by a truck. The notes in the margins the original owner left where a god send when I started programming the C-64.

[@alienrenders]

When I was a kid, took me forever to find this book. Went to a bookstore and asked and they said they could order it. Book cost over 80 dollars. Took me a while to save up. As yes I checked several places and it was even more expensive. Mine was the later softcover binding which isn't as good. But after going through it, it was well worth the money.

[@jim_64s8-bitprojects5]

By the way, the c64 shown on the cover is the same as on the box. It does not have the silver label badges. The commodore badge is black with a silver commodore text, opposite of the real silver labels. Also, the badge around the power LED is a rainbow 64 and ,as noted, the keyboard is a PET font version but with the gray function keys. Probably an early marketing mockup that got photographed and used for a while.

[@Tuxon86]

I still have mine. I also have a french book containing the listing of the kernal. For macine language I used the brown Compute! book of assembler.

[@ScottyBrockway]

We have two of three same favorite commodore books, my third one is Inside Commodore DOS instead of the Raeto West one. 4th would be the complete commodore innerspace anthology Transactor book. I learned assembly from Jim Butterfield's book, what an awesome guy he was. - Fungus

[@williamsquires3070]

(@11:22) - You mention and show that the book has the schematic. The manual that came with the Apple ][+ also had the schematic, as well as pinouts for all the connectors, the joystick/paddle socket, and the expansion card slots. It also had a listing of part of the ROMs as well.

[@MrRobbyvent]

The C64 P.R.G. cost me a fortune for a teen-ager back then. But I wanted it so badly when I saw it in a shop. In Italy, for what I knew, was the only way to have a complete reference of the memory map and the ROM routines and this stuff was pretty rare to find. The italian edition we had was bigger approaching I guess the A4 size and thus very expensive.

[@Lion_McLionhead]

Used to look up character codes & registers from that, but never read the prose sections. Learned to draw schematics with arches where lines crossed over from that book. It was always frustrating that schematic editors & college professors didn't do the same.

[@neilloughran4437]

Fabulous video. I would have loved this book back in 1983/4... unfortunately it was a lot of money for a 14 year old esp as you needed a assembler cart as well to anything.. later I came across a cassette at the local library for a C64 assembler and I got into it but it seemed a kludge...

[@fuzzybad]

Interesting fact about the Z-80 cart section in the PRG! My copy has it, 1st edition, 11th printing (1984)

[@G.B...]

I enjoyed watching this "nerdy" video as much I enjoy watching your videos focusing on programming. Plus I learned a few things I didn't know. Some might think "why do we need to know all those details?". Well, if someone asks that question, he/she is not "nerdy" enough. Plus learning new things is always great, even more when they are related to a great book for your favorite machine.

[@spartonberry]

24:14 As to undefined opcodes on a 6502, I have done that on NES. On Metroid, people spread a known extremely vulgar password (no idea how someone found it) which passes the game's password hash validation check, but results in an invalid game state. Something in the encoded game state data causes the cartridge memory mapper to map the incorrect ROM bank, causing the CPU to jump to garbage data as code. People rumored it could damage the cartridge, but I do not see any cartridge hardware that could be damaged, especially not for the reason people claim "because the played time date gets mapped to like a million years". Especially for a cartridge without battery-backup save. On real hardware, it would crash the CPU, emulators would run in a glitch state, or reset the game (such as the GBA port was coded), depending on their invalid opcode handling. People probably incorrectly thought it was destructive to real hardware because someone made a popular post about it the moment Nintendo launched the 3DS Virtual Console version (the user hard-locked their console). That version was an early-access version given to early adopters and wasn't quite polished yet, such as checking for undefined opcodes, and surely Nintendo patched that after the response but before releasing the final commercial distribution.

[@matti157]

The 1984 italian edition still have the Z80 chapter. Fun fact: the page numbers have been eliminated and the font is that of a typewriter

[@spartonberry]

16:13 Oh, I think that might be source of the text document I have downloaded from the Internet and saved on my computer as a quick reference to the 6502 instruction set (though I have used it for writing NES code).

[@awilliams1701]

Just imagine making a detailed schematic like that of a modern component like a graphics card.

[@colwarsstudiobrickfilmandm8580]

There is also a good book by (i think) robert morris (or something like that) where he talks about many of the things that the refrence guide covers!

[@Potsie]

Quite an interesting and nostalgic look back at (what I assume) many of your viewers did in their childhood. I, like yourself, got a C64 when I was 12 for Christmas. Unlike you however, my brother did read the bit about MON64 and we bought that cartridge. I recall managing to get an A character at the top left corner of the screen, but my 5 year older brother had sprites running around by joystick control in no time which I thought was amazing. Funny thing was that when I started high school (about a month later - the school year here in Australia starts at the end of January) I remember correcting my 'computer studies' teacher in class as I seemed to know more than she did.. I must have been an annoying little s*it... It's only been through watching your videos some 35 odd years later that I have realised how 'bad' the C64 basic was. (Due to commodore not wanting to pay Microsoft for a new version of the pet basic I think). Pretty much Australia wide 'Microbee' computers were used in schools. Instantly having a 'HIRES' command available on the Microbee made graphics so much more attainable...and I then spent a lot more time on programming the Microbee than the C64 (eg. Lots of cursing was required at the Programmers reference guide when trying to count the number of spaces between the dots in the balloon sprite you referred to). Thanks for the video.

[@jim_64s8-bitprojects5]

Agreed! All the comments in my code reference page number in the PRG. Want to select a different screen memory location, comment says goto page 103!

[@Soundfactory24]

Nice explanation about the holy bible for true programming enthusiasts! That reminds me of my beginnings with assembler with the Commodore PLUS4 and its built-in machine language monitor. I have a book "C16, C116, PLUS4 ROM-Listing" from "Markt und Technik" (in German) with 435 pages, where the ROM list was printed out and every assembly line in all routines was documented line by line.

[@vcv6560]

@Robin, indeed the R.C.West tome is such a jewel I bought the VIC version new in`85 even though my 64 was my main computer (later added a used C64 one) just because it was so rich of detail and too damn interesting to pass up. I hope the book club also covers Tool Kit Basic & Tool Kit Kernel by Dan Heeb. Nerd register Store $FF.

[@bald_engineer]

I have been using a PDF for a while. I bought a copy of this one from eBay and it arrived on Monday. It is a third printing. It has the CP/M section on 368. But doesn’t have the Commodorf typo.

[@Brian-vs9sd]

Interesting. My "First printing".. "Second Australian Printing" Text colour for the highlights is more purple than light blue.

[@williamsquires3070]

About the various C64 memory maps (or any other 8-bit system that used a 6502, or derivative): you had to watch out for the stack @ 0x0100-0x01FF; if you clobbered it, your program would crash, but not necessarily instantly! This was so not good, as it would often crash one subroutine call after the problem occurred, or as soon as you returned from the subroutine where the stack got clobbered. It makes me wonder how many people scratched their heads bald trying to figure out problems caused by stack smashing. Another problematic area was 0x0-0xFF (6502 zero-page) as it often has system vectors or other bits of information used by the BASIC interpreter, or the system ROMs.

[@raymondheath7668]

My Programmers Reference Guide is fifth printing 1983 and has the Z80 cartridge info, interesting. My book also mentions the VSP cartridge, but COMMODORE is spelled correctly.

[@diarrhealatte2881]

The Master Memory Map is another classic

[@psyderianlinux6473]

Énorme ! A l'époque ont savait bien faire les choses quand même

[@brucetungsten5714]

Done watching the whole thing - very interesting!

[@wesc6755]

This book + Compute/Gazette + Ahoy = my entire life.

[@bgelais]

I remember i had this book...had the french version tough.

[@Momentvm]

These books were gold! Unfortunately, being over the iron curtain at the time, language and availability was always a problem. Polish books were either non-existent or really bad. What would be the Atari counterparts for these? "Mapping the Atari" ?

[@8_Bit]

Mapping the Atari is the closest I've found so far, yes. I have a lot to learn about the Atari, and overall I've been disappointed by the quality of the Atari books I've found; hopefully there are better books I haven't discovered yet.

[@jgcornell]

I remember buying the Machine Code for VZ200 book years ago and it had just the same problem, it went from ELI5 to Postgrad in complexity like an on/off switch. I never did glean anything from it, except a single POKE to make it go Beep

[@greggiggle]

Is the Vic20 version of this book just as useful? (For the Vic20 of course)

[@8_Bit]

Yes, the VIC-20 Programmer's Reference Guide is a very good book too.

[@VolJoe]

Do you remember zoom copy for the c64? I believe it was the first fastloader that made c64 diskcopy fast. I remember it was translated from German but the translators missed the error codes so errors. So those were entertaining. There was a rumor at the time that it was copywrite material but everyone had a copy of it.

[@m7hacke]

Hi Robin, I have the 11th printing of the PRG and it does have the Z-80 section and does not have the "COMMODORF" typo.

[@baardbi]

This episode was amazing!

[@meneerjansen00]

Wish they'd reprint the Programmers Ref. Guide. I have to read it form PDf and it's agony to browse through. Only hard copy is suited to quickly go back an forth from a chapters text to an appendix to look things up etc.

[@jack002tuber]

I wonder if a print shop would print one?

[@meneerjansen00]

@@jack002tuber Might be a solution. Wouldn't look very good, but better than reading off a screen.

[@ImYourProblem]

Thanks, Rob.. love your vids man

[@tiborzic]

? C64 was and is the greatest machine ever, keep up with it... love your episodes, and we send you cheers from Slovenia

[@machinebyte7235]

and from Poland too

[@MichaelDoornbos]

I was troubleshooting a bug and thought I should review the kernal routines I was using. I have three versions of the PRG. On P290, the PLOT kernal routine, and I noticed something odd. Had to break out my other versions as it was late and I thought maybe my mind was fooling me. It has something different for each of the three versions: Second printing(1982) - Y is the column number of the cursor location (0-79) Third Printing(1983) - Y is the column number of the cursor location (6-39). 6! Weird. The other one I have is a Twenty First Printing (1989) and it's correct there, 0-39. I wonder what version was the first it's actually fixed in.

[@8_Bit]

Nice, I hadn't noticed that one! I wonder how many other small corrections/changes like that were snuck in. I wonder if the "6" was someone mis-reading a sloppily written zero. It seems to frequently take Commodore 3 tries to get things right :)

[@MichaelDoornbos]

@@8_Bit Yeah, a hasty 0 in red pen or something could have been read incorrectly by the typesetter. Hadn't thought of that. It's the routine I use the most second to $FFD2 and I guess I'd never read that paragraph very carefully before. I HAVE run into trouble not clearing the carry on that one from time to time.

[@haweater1555]

I always thought the worst part of the book was the overstuffed binding, so many pages that turning them will wear out the holes and fall out. The VIC20' Programmers Reference Guide, while thinner, has an appropriate sized binding that won't tear pages.

[@JGreen-le8xx]

I have a 1st Edition 10th printing 1984. It has the censored material as well. Also have Commodore 64 User's Guide 1st Edition 2nd printing May 1983

[@roaddan01]

Hi Robin, I have found an error in the french Canadian version of the Programmers Guide. On page 250, the ROL instruction omits the possible carry modification of the instruction. Also, tired of looking in books for mnemonics details, I have made myself a 6502 assembly mnemonics quick reference card both in alphabetical and numerical order fitting on a legal size recto/verso sheet. I was thinking of sending it to you so you could share it with your viewers but I dont know how. Interested ? Keep on the good work.

[@8_Bit]

Hi Daniel, cool, I don't think I knew there was a French-Canadian version of the PRG! I do have a few french C64 books now though that I got last year. If you go to the About tab on my KZbin channel page, you can get my email address if you want to write. Thanks.

[@roaddan01]

@@8_Bit Well it is probably not a French Canadian version. It is most likely a France French version. Canada with it’s 9 to 10 million francophone population do not have a big enough market to get it’s own translation. Then again maybe. However, I will send a zip file containing a pdf version of tables and the searchable ms-excel version of the table. All in English of course. Fell free to add any correction. Best regards.

[@speedbird737]

@ 30:20 Commodore the Microcomputer Magazine available here archive.org/search.php?query=commodore%20the%20microcomputer%20magazine

[@HelloKittyFanMan.]

"...It only had 38K..." Closer to 39K in that message, actually.

[@speedbird737]

@ 30:20 Power/Play Magazines available here archive.org/details/commodore-power-play-magazine

[@rager1969]

Interesting pronunciation of flag. Do you say it the same way when talking about a national, regional or organisational flag, like the Canadian flag, California flag or POW/MIA flag?

[@DaveF.]

Hmm - my copy was spiral bound rather than with those flat white ties. And it did have the z80 section.

[@CobraTheSpacePirate]

OH man! I got rid of mine back in the 90's!!!

[@8_Bit]

I'm very sorry to hear that!

[@AndrewKroll]

Still have my original copies, and lots of others, some of them aren't CBM related and are actually binders. 🤓

[@andlabs]

classiccmp.org has a PDF of the second printing. It DOES have COMMODORF! www.classiccmp.org/cini/pdf/Commodore/C64%20Programmer%27s%20Reference%20Guide.pdf commodore.ca seems to have the third printing split by chapters, and it doesn't have COMMODORF: www.commodore.ca/manuals/c64_programmers_reference/c64-programmers_reference_guide-03-programming_graphics.pdf (Of course that assumes that these PDFs are all scanned from the same book, and the quality appears to be low here...) 35:31 At least the C64 PRM talks about how to make an auto-start ROM (on page 263). The VIC-20 PRM just mentions that auto-start ROMs are possible, but never talks about how to make them (which I wanted to know so I could disassemble those HAL games from a few videos back). I managed to find a brief discussion on how to do so.... on some university student's term paper about using the VIC-20 as the basis for some medical device. vtechworks.lib.vt.edu/bitstream/handle/10919/76031/LD5655.V855_1985.B744.pdf?sequence=1&isAllowed=y I wonder if Commodore back then didn't want people making and selling their own cartridges, which would, combined with how Atari handled programmers on their computers and how Commodore sold Infocom games using the standardized C64 branding, make sense for the time??? (That didn't stop companies like Thorn EMI from making VIC-20 cartridges anyway.)

[@Sumaleth]

Is that a mistake on page 110: "Tip: Reversed characters are just characters with their bit patterns in character memory reversed." Should that be inversed? :) This was a foundational text for me as a kid too. I read it, and reread it, and reread it until I understood everything.

[@8_Bit]

Good catch, I had forgotten about that. I'd call it a semi-mistake, but also it's a Commodore-ism like the misspelling of "KERNAL". The bit patterns are inverted, but since the first PET they've been calling those upper 128 characters "reverse characters" or "reverse video", even using the RVS abbreviation on the keyboard, so they may have just been trying to explain and define their terminology even though it's not literally correct. It's interesting how loose with language some of the 8-bit pioneers were. I occasionally use some Jim Butterfield-isms like saying "The Commodore" or "The VIC" in my videos, and I'll get comments about how I should have said "The Commodore 64" or "The VIC-II" etc. :)

[@bierundkippen720]

Why are PLOT and CHROUT good for game programming? Isn't it much faster to put the characters directly into screen RAM?

[@8_Bit]

Yeah, it's much more efficient to just directly store the characters into screen RAM. I'm sure I didn't make this clear enough in the video, but my comment was mostly a 1984-era memory, when I was reading the PRG before I learned machine language, and a PLOT was a thing I was missing. My previous Timex/Sinclair 1000 computer, as poor as it was, had a PLOT (or was it PRINT AT?) BASIC command and that random access of the screen was great.