Commodore 64 is Boss: Datassette Motor and Location $01

[@boler6502]

I got lost for a second on address EA73 at 38:54 into the video, as you say "If it was zero, it's going to branch ahead, but, if it wasn't zero, then.....", when I think you meant to say it the other way around. The opcode is BNE, which should branch if $C0 is 1 - 255, not 0, right? I believe you continued to trace the code correctly, just this little hiccup when describing the state of $C0.?.?. Please feel free to delete this if I'm right and you decide to add a correction before posting on the main channel. Otherwise, please straighten me out. Thanks SOOOO Much for your vids. \boler

[@8_Bit]

I think you're right! Whoops. Given the worse bloopers I've made in other videos, I don't think I'll do another render and upload for this one. I will pin your comment as a warning to others, and other sharp-eared viewers who noticed get +100 points. You of course, get +1000 points for being first :)

[@PieFights]

@@8_Bit Just to point out that CDS also made Frantic Freddie

[@kcmule]

My comfort level with the Datasette in the 80s helped me get hired by a tape storage company in the 90s (StorageTek) and thus launched my computer career. Thanks Commodore!

[@PedroGoncalves.DSGProAudio]

I absolutely love cassettes ❤📼

[@TheLiquidLunchMan]

If I recall, Jet Set Willy (UK tape version) used this tape control as an anti piracy measure. They 'exacto' cut the tape length so that the datassette would click stop at a predetermined millisecond time range after the game load - giving another indication of a real tape vs a tape copy. As you couldn't hear the tape data audio, and there was no screen indication, you had no idea when to stop the copied tape manually.

[@phill6859]

Are you sure it was jet set willy? It had that colour sheet and I don't remember it being hard to copy the tape.

[@TheGreatAtario]

Wouldn't that prevent people from using ordinary cassette decks?

[@marksims3904]

The Last V8, the music by Rob Hubbard was incredible!!! Great video Robin, love the C64!!

[@randysmith7094]

Back in the late 80's we had a type in program that let us digitize a short audio clip from audio cassettes onto the C64. Most of the time it produced very distorted audio samples but we had fun playing with it. Might be an interesting revisit. I have no idea what magazine it was from, my cousin typed it in.

[@davideocassette6312]

I remember seeing a version of that program in a magazine but it was for the Plus/4. Very frustrating because I'm sure the C64 can do the same thing but I never found an equivalent listing for it.

[@saszab]

If you know assembler you can easily write such a program. I did this 30+ years ago for my DIY ZX Spectrum clone. It stored several seconds of 1-bit sound in ~40K of memory and then played it.

[@phill6859]

​@@davideocassette6312I'm sure I have seen one, I also wrote one. It's awful though because the c2n only lets you detect a zero crossing from + to -.

[@TVSAT90s-oz7sm]

interesting! didnt know about, it's in german magazine 64er 12/84 page 84 saw it here from 26:12 kzbin.info/www/bejne/r4e8oWOfe6qFrNEsi=Kq-AxnPiqNr6IbbH

[@hankw69]

My family had a Vic-20 in the early 80's with the datasette. When I went to Great Britain in the service I bought a C-128 and my roommate had a bread-bin 64. The British software scene was still(1987-89) very cassette heavy so I asked my folks to send the datasette. We had a blast playing games picked up at flea markets for one pound each. Fun times.

[@Electronics-Rocks]

Very interesting as repaired so many C64 & written code for it!! I had a C128 with a 1570 38 years ago & most of my code using the tape deck was on the Vic20! Always a school day!

[@Bobbel888]

Cool! Do you maintain that code on current emulators?

[@ChrisKewl]

Robin: From the west side of Cleveland and I used tapes a lot, especially for my old basic programs. I am also 45 years old, so I came into the C64/128 pretty late.

[@whomigazone]

North America, all my friends used them with their VIC20s and 64s, I was the first person in the group to get the 1541. Still have the Datassette unit.

[@WhileTrueCode]

i remember typing in one of the longest ZX81 games from my dads book, "saving" it to household cassette recorder, then re-loading to test.. before ever running it.. needless to say, the tone/volume knobs got me...

[@thenorseguy2495]

It’s Friday and we get a new video from Robin. What a great day

[@sprint955st]

C2N shape my favourite, best shape. All my Spectrum buddies moaned like hell about tape loading difficulty, I had none whatsoever on my VIC or 64. As I recall, Beach Head stopped and started the tape as it loaded. Here in the U.K. yes most people had tape not disk, the 1541 cost as much if not more than the 64. But for my 16th birthday my Dad very generously bought me a bread bin 64, 1541 drive and a MPS803 printer too - because a) he didn’t want me to have a moped (16 is the legal age here) and b) to ostensibly help me with computer studies. I did a fair amount of programming, and have worked in IT 35 years. Thanks Dad! RIP.

[@timsmith2525]

Fascinating! I never would have guessed that there was so much interaction between the kernel and the cassette hardware. I alway thought it was just a cassette player with data lines.

[@simonstapletondotcom]

Hi Robin - boy this was a blast from the past. In my early teens (40 years ago) I had a Plus/4 and I remember hacking all the memory addresses for fun, and discovered a poke to switch the tape motor on and off. So I played monosyllabic tunes on the motor purely from basic. Nerdy, geeky, not something I have admitted to another human being before, until now!

[@stewkenly9453]

Love the detailed explanation! I’m relatively new to the C64 world. I grew up with the Coco 2&3. I seem to recall those had a motor on/off basic command. Fun to learn new things! Thanks for the great memories.

[@00Skyfox]

Wonderfully detailed and in-depth description! Thanks

[@thefamouseccles1827]

In the UK, for some reason the disk drive cost as much as the 64 did in many cases, and games on disc were twice the price. Wasn't so much wealth in the country in the early 80s, and to compete with the lower cost ZX Spectrum, tapes are where it was

[@Commodore128Mode3]

Thanks Robin! Another great episode. Of course, many games were released only on cassette tape, so I was likely one of those few who used my datasette on my 128 back in the day :) Also in the C128 mode, when a program was FOUND, using the Commodore key would load the displayed program that was FOUND whereas pressing the space bar would skip the displayed FOUND program.

[@HenrikDanielsson]

Having been listening to SLAYRadio for years but never having actually used a C64 more than a few times, it's so nice to see where all those tunes came from.

[@stefanjohansson3578]

Robin your videos are always full of surprises and NO they´re not to long, always make my day when you release a new one. Love this kind of hardware/software deepdive hacking stuff! C64ever!

[@38911bytefree]

Not many games were gentle enough to cut the motor once it loaded. As our 1531 was sooo delicate on azimuth missaligment we need to dampen manually the play key by hand to soften it is retunr Otherwise azimuth got kicked out of alligment after some time. Once our game did load, we would start to play and forgot about stopping gently the tape. Eventually if motor was let running by the game, tape will reach the end, the autostop will kick and let the play function return kinda hard. A bit silly thing but at the time we got out datasette serviced, the guys didnt bother to lock the azimuth screw. And the azimuth drifted easily with normal use. I had a generic datasette later and even the the mecha was almost the same (I think it is Hitachi's), we didnt got any azymuth issues, and if a correction was needed, it will last no problem.

[@MariaEngstrom]

I seem to remember that the game Silent Service actually used the cassette motor, it pulsed it, to simulate the submarine engine sound on the C64. 🤔

[@38911bytefree]

The motor uses an integrated speed regulator, like any other 80s takpe deck. I dont think it would be possible to pulse the motor fast enough because you would be pulsing the speed control IC and not the actual windings. But in the cas it worked, would be a nice way to stress the motor speed control.

[@DMStern]

I remember reading about some game (I want to say Into the Eagle's Nest) using the motor to simulate enemy footsteps. I never got it working, but maybe the feature was only included in the cassette version?

[@jussikuusela7345]

My maternal grandpa had a Sony reel-to-reel mono deck that had a microphone with a remote switch... and the dual plug had a 3,5mm and 2,5mm barrel with fixed spacing. It also fit my aunt's Sony mono "boombox". Now, it would be neat to know if some other manufacturers adopted the same spacing even if they supplied their own mic/remote sets with semi-detached plugs or even separate remote buttons. You probably have also noticed that when you turn the C64 on, or reset it, the tape motor will spin for a fraction of a second even if no button is pressed.

[@lougarou007]

I knew these different datasette sounds where really there. Thanks for the video

[@The_Last_Ninja]

This video couldn’t be timed more perfectly! Yesterday I serviced my C2N Datasette and my Turbo model Datasette and adjusted both Azimuth’s so that I could play copied .tap files from PC to cassette on my original hardware. I recently purchased a new old stock tape recorder for coping original games from PC to blank cassette tape and wanted to play the games as they were intended, so I can have the authentic Commodore 64 experience. Even though the disk drive was light speed compared to the datasette, for me this is where it’s at in regard to the Commodore 64…ultimate nostalgia achieved.

[@andrewgillham1907]

So are you saying you weren’t keeping up with the Commodore? Great video, it reminds me I wanted to spend more time with a datassette and some early tapes myself.

[@8_Bit]

As I was making another editing pass on this yesterday it did occur to me that I missed out on some kind of "keeping up with Commodore" reference in all this :)

[@piwex69]

I remember the some titles for Atari 8-bit family used to be issued on the combined data/audio cassettes. The proprietary cassette unit (I had the Atari 1010 tape recorder) was stereo, with one track for Data, second track for music to ease enormously long waiting time . The music played through the monitor's speaker. My 1010 run out of favor because of cheap plastic levers had broken off and there was no way to glue them back. I saved for the Atari 1050 disk drive and that was the revelation....

[@KennethSorling]

Very interesting. A viable use for this doesn't immediately spring to mind, but knowing about this may come in handy one day. Oh, and I live in Sweden. In Europe we used Datasettes a lot. Most C-64 users' first external storage device was one of these babies. Especially since the 1541 was so dang expensive. Our parents didn't wanna fork over the dough for it if there was a cheaper alternative available. Incidentally, I started writing my second novel at 16 on a C-64 with a cartridge-based word processor. The Datasette was my storage medium, at least for a while. I still have the tape.

[@uriituw]

I was always fascinated by what games did to the motor back in the day.

[@HelloKittyFanMan]

Not only Canada and USA, but Mexico and those smaller, island countries.

[@thoralfkleint2102]

Hi, try Ghouls ’n Ghosts for cassette. If you load the intro, the tape stops after loading and run the game. When you want to get to the first level, the tape starts and read it, stops again. For the other levels the same. When you finish the game, rewind the tape and press play and joystick button to continue. It seeks for the first level by skiping the intro, its alsways in the ram.

[@Isaac_Garcia_Peveri]

I knew since my childhood that was always the c64 the master, and the Datassette the slave, and I was always wondering how the C64 was controlling it. Thanks man.

[@KAPTKipper]

I used a tape from my PET with my C64 in 83. I wasn't long saving money for a 1541 drive. My PET tape deck has no grounding strap. It is an internal mounted one. I bought exactly ONE tape, Avalon Hill's "Midway Campaign". I recently uploaded the tape to the Internet Archive because it had 5 different computer systems supported on it and one had not been archived. Didn't several disk FASTLOADERs disable the tape routines, because they replaced the code with their fast loader?

[@bluerizlagirl]

I'm currently working on a 6502 coding project myself (full PCB CAD, from SPICE deck to Gerber files, on a BBC Micro!) It's always nice to see how someone else did things Back In The Day and whether it's like anything I've done. I've certainly used no shortage of "branch effectively always" constructs; as well as making use of the known carry state, after a BCC or BCS succeeds or falls through, potentially to save a CLC or SEC.

[@HelloKittyFanMan]

This was really interesting, Robin; I love to keep learning new things about my favorite 4-decade-old computer! But then the sad part is that they make me wish I had known about them way back then. Oh well, better now than never, eh? "Cool beans!"

[@LordmonkeyTRM]

As an Amstrad CPC 464 user never needed an external. The tape player was bomb proof too would load pretty much every thing I threw at it.

[@NuntiusLegis]

C64 person here, but I envied the Amstrad design until the C64 C came out.

[@timsmith2525]

I used a Radio Shack cassette player with my TS-1000 and the Commodore Datasette with my 64.

[@mbvideoselection]

I used to save a menu program at the start of my cassettes into which I created a directory of other programs and files on the cassette. The add routine would ask me to input a filename, then ask me to press fast forward on the tape until it got to the right counter position for the program. It would monitor for me pressing Stop and, when i did, it would remember the amount of time it took using TI. The program then used the send keys trick to add a DATA line to itself containing the filename and timecode. When running the program in normal mode, it would get me to choose the file i wanted, ask me to press fast forward, automatically stop the motor at the right position, then tell me to press Stop. Then it would go into normal Load mode with Press Play On Tape.

[@damouze]

Interesting video! I never owned a C64, so this is very educational to me. At the same time I get the feeling that other platforms didn't really do things in a fundamentally different way when dealing with datarecorders (using the generic term here). The specifics will vary, but in the end the computer still needs a bit stream to analyze and follow. The MSX for instance, works with regular datarecorders and cassette decks, but has built-in circuitry to transform the analog signal into a bit stream and vice versa (I actually have a replica of that circuit as a KiCAD project) and it too has motor control. Which makes me wonder if one could abuse this circuitry to have it output a high frequency pulse width modulated audio signal... Or use it to connect two computers together...

[@jbeckva499]

Good points about using a non proprietary deck, but about that SuperScope Cassette Deck - That had a heck of a lot of features compared to ones I remember. Stereo? Speakers too, Left and Right? Never seen ones like that other than mono portables from RadioShack. Neat

[@HelloKittyFanMan]

Oh wow, you just coded a little bit of crude PWM to the tape motor!

[@SM-rn3xy]

17:25 When you press the Tape Motor button on Lazer Force do you have some sort of auto-fire going on your joystick? It could be toggling it on/off rapidly as a result like a PWM signal. I used a dongle with my C64 (and later C128 until I got a 1571) to use a normal cassette player as I already had one for music and my C64 and wouldn't want to buy a second one without a speaker.

[@iansorbello9693]

I’ve never seen past the first corner in the last v8 ever. Nice side distraction ;)

[@falksweden]

Speaking of Swedish C64's. I remember that the first C64:s available in Sweden had a British keyboard, but a Swedish character ROM was available to buy, complete with brown stickers for the keys. Life in the 80's... 😁

[@atkelar]

I had fun with tape storage for my MPF-I video; it offers tape for a "large storage medie" solution. But the input lacked a proper decoupling so the input signal somehow didn't make it to zero ever. I had to cobble a little filter cable together to make it work. So yes, a pure direct connection with a specialized deck is certainly good. My (short) C-64 time didn't have a tape as it was on the SX-64 of my mom's cousin.

[@MrMaxeemum]

I knew it was under control of the C64 because when you load a tape, the motor pauses when the program is found and starts again after some seconds or the SPACE BAR or CBM key is pressed. I believe this was done because the C64 tape load routine needed screen time to process and store the data (don't know why though), so the screen was blanked and if it was blanked you wouldn't see if or when a program had been found. The screen blanking isn't done on the VIC20 so doesn't pause when a program is found. I think the VIC20 stopped the motor after loading, so I guess it is controlled the same way.

[@NuntiusLegis]

The VIC II graphics processor in the C64 steals a few CPU cycles for fetching certain data, which would interfere with the precise timing needed for tape operation, that's why the KERNAL of the C64 was modified that way, switching off the VIC II so that the screen blanks to the border color. I think this is also the reason why the 1541 on the C64 is slightly slower than the 1540 on the VIC 20.

[@CityXen]

Never had a datassette, started with a 1541, so can't relate to the experience. Although I have one now, might be fun to experiment with at some point.

[@NuntiusLegis]

There's nothing wrong with using the Datassette: With fastloader/saver (most convenient on a cartridge) it is fast enough for small or medium-sized files, and this should increase the lifespan of the 1541 which is less robust than the Datassette. A last save using the KERNAL routines to a Datassette in good condition with a quality tape at the end of a programming session (when time is not important, you can brush your teeth or something) is a good backup.

[@timsmith2525]

Ah! The sound of cassette tapes being inserted and removed!

[@TheUtuber999]

21:36 If a line is disconnected, it would be floating, and its value would be indeterminate. It's probably just being pulled low with a pulldown resistor. It would be a value of "1" if it were pulled high with a pullup resistor. It all depends on which way the circuit was designed.

[@mikegarland4500]

Ahh, so I had the one you show second, at about 0:12 since the other was way too modern looking to be the one I had. Mine was definitely more boxy and looked like a regular tape recorder you could buy at the time. I used it for at least a year, maybe 2, before my dad got me the 1541 disk drive. I used to make my own "mix tapes" of programs I wanted to keep on the cassettes by dubbing them on another tape with a dual cassette deck. I would keep "working cassettes" but then have a single "backup" tape that I would listen to the sounds on the tape to find the ends of the programs. I had no idea at the time why the Datasette made 2 copies of the programs. It wasn't until later that I learned why and how they were used in case of data failure in the first copies. I'm sure I wrote over the 2nd copies of the program at least a few times before I realized they were even on there... memory is fuzzy at best.

[@8_Bit]

Yes, sounds like you had a PET-era datasette, or maybe the very first VIC-20 era unit, before they went to the rounded one I use in most of this video. re: two copies of each program, that's something I really need to look into for myself some time. I've heard that many times but I've never seen a good explanation of exactly how things are laid out on tape, and if in fact there really is any automatic attempt at using the 2nd copy if the first one fails. Whenever I see load errors on cassette, they seem to happen immediately and don't seem to try to use the 2nd copy. So when I eventually study this, I'll be looking to find out what the save and load routines actually do, and if/when that 2nd copy comes into play. Let me know if you ever find any good details about it!

[@8_Bit]

I've just found there's actually a pretty good article on C64 wiki about "Datassette Encoding" which explains that the data/payload is actually repeated twice within each 192-byte data block. So it's not two copies of the program stored one after the other, but each block is repeated before moving on to the next one. I haven't found out yet if it actually tries to take the best of each copy of each block, or if it just fails if it detects a difference.

[@thefamouseccles1827]

Presumably Warren Pilkington of Zzap64 and Commodore Format fame...

[@RetroCave-wr9tl]

My C64's I/O chip was messed up at some point. I did not know what was wrong with it, but I observed 2 weird behaviors: 1. Random pulsating of that part that you showed during Cauldron gameplay 2. SYS1 would lock up the computer instead of clearing the page. I spent my childhood on that datasette. I had to install a little buzzer for easy azimuth adjustment as I developed an ear for the clean data sound at 300 baud😅

[@WhiskeyTango-h7q]

FYI - on the datassettes I've used, there is enough space to coil up the ground lead inside the connector housing, making for a much more orderly looking cable.

[@HelloKittyFanMan]

Interesting that the control circuitry in the Datasette is so different from a regular tape recorder that the signal goes out to the computer and back just to run it even when the computer isn't actively commanding it, and that it's linked to whatever runs the cursor speed! But as for when you reset the computer, could that be more about just interrupting the power to the drive?

[@suvetar]

@10:28 Y'know, now I've got a relatively decent set of speakers (as PC speakers go anyway! Logitech Z685) I still catch myself being surprised but so pleasantly so, to hear a Sid tune that takes advantage of the dynamic range!

[@amalgamatedsociologicalins6680]

All this time I thought it only could stop the tape. Could it be leftover functionality from the PET when the tape device was built in? Get rid of the chunky buttons and you are most of the way towards fully automated.

[@moshly64]

Can you do a video on tape fast loaders & how they work?

[@HelloKittyFanMan]

Oh my heck, I remember when you showed us that we could stop the cursor blink but I didn't know until now that we could set it to keep blinking but slower, and that that also affects typing responsiveness! Do you think that's one of those accidental poke things?

[@NuntiusLegis]

It is quite a common topic in C64 books to slow down the interrupt or skip parts of the IRQ routine to make the main program faster. Doesn't have a big effect though.

[@HelloKittyFanMan]

@@NuntiusLegis: Interesting. I must not have read my fair share of those books then!

[@dewdude]

Those Superscope tape units were made by Sony. They were really good tape units.

[@HelloKittyFanMan]

"The Commodore can't tell the difference..." Which one can't tell the difference?

[@TheSimTetuChannel]

Very interesting! I didn't realize the Commodore datasette controls were basically just an external keypad.

[@HelloKittyFanMan]

But any time rew/FF are working, that hum will be there. But the sound of the gears that drive the reel spindles might just overpower the sound of the motor running by itself with just the capstan.

[@g.h.190]

I had the impression power was cut to cassette port during a reset, apparently more was going on...

[@amirtavakol8256]

Hi Robin , if you have access to pp hammer cassette version please take a look at it an smart tape loader which blowed my mind

[@Breakfast_of_Champions]

The only thing that still needs adjusting sometimes is the head position screw on the Datasette. But that's really easy with visual feedback provided by Turbotape. That's another thing generic tape recorders had much more difficulty with.

[@NuntiusLegis]

I think most adjustment problems result from that screw being too much of a temptation. ;-)

[@TesseractUnfolded]

Could this magic be used to make a muti-game datasette that presents a menu on screen and can automatically fast forward to the right part of the tape to begin reading a selected game?

[@NuntiusLegis]

The excellent "Cassette Book for the Commodore 64 (And Vic-20)" by Dirk Paulissen (German version: "Das Cassetten-Buch zu Commodore 64 und VC-20") has a neat BASIC program that does exactly that, using similar techniques as in this video, to have a "directory" at the beginning of a cassette.

[@mkl-68k]

ACOS+ from Melbourne House did that. (Advanced Cassette Operating System)

[@rickyderocher3181]

Is the jittering in Road Toad the result of a NTSC / PAL issue?

[@alangoddard6167]

Hi Robin, great videos btw.. Can you please tell me or show me, how you get the Kung Fu Flash to accept the super snapshot crt files please. It’s driving me crazy.. Thanks Alan…UK subscriber

[@Kobold666]

I wondered if a faster serial port could be implemented using the cassette port than on the IEC port because it's directly connected to the 6510. But it really is just a memory read from zero page and that direct connection has no benefits at all to the software side of things.

[@HelloKittyFanMan]

"I'm gonna be loading it from disk today..." OK, when? So far only from the cartridge.

[@ownpj]

34:39 And if you connect pins 4 and L on the userport you can cascade both timers on both CIAs.

[@SmoggyLambGG]

That tape recorder has four-way power. OK, it uses AC, DC, batteries, what's the 4th method of getting power?

[@HelloKittyFanMan]

"...Our BASIC program can't turn the motor on or off..." Well it _can;_ you just got done saying so. But the running kernel ("Kernal") ML turns it right back the other way.

[@50shadesofbeige88]

10:20 This song slaps.

[@HelloKittyFanMan]

OK, but then what about poking a decimal number directly and just skipping the Boolean logic?

[@NuntiusLegis]

Should be possible if you use the standard values, but that might cause problems in non-standard situations.

[@HelloKittyFanMan]

Huh, how weird that the tape capstan runs all the time under some software. That always-spinning business for storage certainly reminds me of a hard disk! Any idea why that particular game would have it do that? I mean: I see that motor option there, but I didn't fully understand your explanation of what the point of that is.

[@NuntiusLegis]

Doesn't every audio cassette deck do that as well when powered on?

[@HelloKittyFanMan]

Nope, @@NuntiusLegis!

[@NuntiusLegis]

@@HelloKittyFanMan Tested it with two decks I have around, one (Sharp) does it, one (Philips) doesn't.

[@HelloKittyFanMan]

@@NuntiusLegis, you're saying that the whole time you have working batteries in the Sharp one its motor is running? Because if that's the case then something's wrong with it, because that's not supposed to happen.

[@NuntiusLegis]

@@HelloKittyFanMan The Sharp one is a HiFi deck without battery compartment. The Philips is a programmable cassette / radio / digital clock unit; it has a battery compartment, but only to back up the clock.

[@BruceLaing-f7t]

We, too stayed on cassette in Australia, due to the cost of 1541 disk drives (cosying almost as much as the commodore 64 at the time ($499 for the C64, and the same for the 1541) which is the reason turbotabe became common.

[@CallousCoder]

I’m always amazed that I see Rob load games I’ve never seen before! I love that Halloween game.

[@RandomBitzzz]

I'm in the US and our family started out with a datassette on our bread bin. We suffered with it for about a year before we got a second hand printer and MSD floppy drive. We did have fun splitting the cost of the disk+tape combo pack software with a family friend - they took the disk and we took the take.

[@fliplefrog8843]

Something i missed? U put in the cassette and load the Game from Disk? Tape has no inventory(Dir)

[@NuntiusLegis]

He loaded from disk to save time.

[@rafalklepinski7372]

Great episode! I happen to have a 1531 Datasette box right by the monitor! It's been sitting there for years. First use was a breadbox 64 with a 1531 with the C16 plug which had to be cut off and soldered directly to the connector on the 64. Got both the 64 and 1531 at the same time at Canadian Tire of all places. Fond memories of borrowing software tapes from school and using the stereo to copy them. Alas school had a PET so most software was not compatible 🤣 But there were functional exceptions. This 64 and 1531 combo got me started on an IT path.

[@NuntiusLegis]

There are adapters to use the 1531 on the C64.

[@rafalklepinski7372]

@@NuntiusLegis Maybe there are but I guess Canadian Tire wasn't selling any in 1986. :)

[@jendak7921]

I had 1541 and datasette and was courius why datassete motor is running sometimes when playing games and it was loaded from floppy. My dad said it's because game was programmed for casette then copied to diskette and didn't know where it came from so still checking tape. It looks like it was half of truth. When datasette broke down mechanically I tried connect datasette cable read/write/gnd pin with out/in/gnd 5DIN on Aiwa stereo250 and other tape recorder without knowledge how it exactly work and it didn't work as expected. My all three C64 computer (two flat, one big), two 1541, datasette, diskettes, power supplies, graphic writing unit XY4150 (made in Czech Republic), joysticks, cartridges.. were stolen in 2004. I still have casettes because it was on other place and believed one day I can converted them somehow into image and play in emulator on PC.

[@FlyingSurprise]

Let's write a routine to stream data (text maybe) from the tape deck and print it on the screen in realtime.

[@PaulHockerOnEarth]

Only Robin has the skills to make a video about a cassette deck be interesting. Bravo!

[@NuntiusLegis]

I am a big Datassette enthusiast and find everythimng about it interesting.

[@csbruce]

1:37 Why didn't they just put a shield-grounding pin in the connector? 10:37 Is there actually a penalty for rolling off the road? 11:44 That's what BIC pens are for! 27:51 Is the time between interrupts exactly the number of cycles you set, or are there one or two extra cycles to reload the register, etc.? Does it interrupt on hitting $0000 or when the counter underflows? 29:14 Your BASIC program will also run a little faster now that less system overhead is being taken by IRQs. 33:45 You've selected an interrupt interval of 16.3 seconds.

[@8_Bit]

No penalty for leaving the road in Last V8 - but if you hit any of the obstacles, even the shrubs or whatever, it's insta-death. I haven't done a full investigation of the CIA timers but as far as I know the IRQ occurs when $0000 is hit, and it's only at $0000 for one cycle and then it's reloaded at the max. value. I'm fairly sure that in the past I've set the counter to 65 decimal to match the NTSC scan line length, and the resulting code was horizontally synced with the raster. I'm not sure if I still have this code but it would be a neat thing to investigate again.

[@wembleyford]

Oh, that's impressive - I think I've only ever got to the second stage in The Last V8 perhaps half a dozen times back in the eighties. Horrible game - but worth £2.99 just for the music

[@Bobbel888]

nice memory.

[@mikgus]

The big takeaway from this video is that some people kept the grounding cable!

[@8_Bit]

Did you just cut it off? I was very reluctant to do things like that, and didn't know anyone who knew better.

[@mikgus]

@@8_Bit I believe a friend did it first and then we all did it. None of us had seen a Pet back then so we couldn't figure out a use for it.

[@G7VFY]

Cools games I have never seen.

[@ChrisCebelenski]

Never used tape on my C64, even in the early days - started with the 1541 right away, and then bought the single-drive version of the MSD and dumped the 1541. The downside of the MSD was that a lot of copy protected software (and fast-loaders) wouldn't work with it, one of which was solvable. I did use tape with the TRS-80 Model 1, but only for a few weeks before that got really old and I moved to disk (TRSDOS is a whole nuther subject). The "ultimate" tape drive was DECTape, which was block addressable and allowed for random access! Slower than a disk, yes, but still nice enough, especially when compared to the paper-tape alternative that I had. I guess the modern version would be LTO tape, but at those scales the physical medium itself becomes a limit.

[@HelloKittyFanMan]

"1/60th," Robin? That doesn't make sense. How do we pronounce just "1/60" in fraction form? It's _already_ "one sixtieth." So what would "1/60th" sound like?

[@desertfish74]

That ground wire was DEATH for the C64 user port, it killed a CIA in mine when it short circuited something. Bad Bad Bad

[@8_Bit]

Bizarre that Commodore didn't even mention the ground wire in the 3 different Datassette manuals I looked at. It was not just an extra manufacturing expense that 99% of their users didn't need, but it was an actual hazard to computer health.

[@NuntiusLegis]

That was extremely bad luck. I like that Commodore still cared about backwards compatibility then.

[@markjreed]

Totally had a Datasette with my VIC-20, and continued to use it with my C128 for a while before we could finally afford to get a 1571 to go with it . . .

[@thenoblerot]

I used the 6 volt motor control of the PET cassette port to power an Arduino that drives my PET's custom rgb led keyboard. (I can power cycle the Arduino, and control the rgb from the PET User Port.) It took me an embarrassing amount of googling to learn of the Interlock!

[@8_Bit]

That interlock feature seems to be barely documented.

[@NotIT]

I also had the Datassette with my C64 as a kid growing up in Michigan (closer to Windsor that Thunder Bay though). Probably used it for 2+ years before I finally bugged my parents enough to shell out for a 1541. So I had a decent library of tape based games.

[@Trompunitalphapropan]

There were 64 likes, poked it to 65! Sorry ;)

[@hammondeggsmusic]

Yep, used this with the Vic and then a breadbin c64, but got a 1541 with a c64C later. For the Vic even with the super expander (an extra 3K..!) it wasn’t unreasonable to use really…

[@awilliams1701]

I was under the impression the C64 could disable the motor optionally. Then again I've never used a tape. I have the U2+ tape adapter.......and have never used that either.

[@falksweden]

I'm also one of the few that used a Datassette with my C128. Used the same I used with my C64. But I removed the annoying ground strap from the plug. :)

[@FuerstBerg]

When I remember right the user loses control over the motor as soon as a BASIC program runs. The motor then runs only with pressed buttons and IO operations (LOAD from tape, reading from or writing to a file; SAVE could work, too, but makes less sense). Maybe after the end of a LOAD, VERIFY, or SAFE you need to press stop to re-enable the motor. I never tested if the capstan runs by set motor bit. I never cared about the mechanics of a tape drive as a teenager, a new datasette was too expensive.