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22

The big improvement to the language in Locomotive BASIC, compared to Sinclair BASIC (and many other BASICs), was the addition of timer support: AFTER 50,0 GOSUB 320 would call the subroutine at line 320 after a second, and EVERY 500,0 GOSUB 320 would call the subroutine every ten seconds. In both cases, the first value is the interval in fiftieths of a ...


20

Was Locomotive BASIC significantly better than Sinclair BASIC? TL;DR: Oh, yes, it was! I'm aware that both Basics were more advanced than the C64 Microsoft implementation, Comparison of C64 BASIC to other BASICs of the same time is never in favour for the C64, as it's a quick port of the original 1977 PET Version. but neither [Locomotive BASIC, ...


20

Yes, it is possible. There are a number of ways: If your TV has a SCART connector, you need a cable adapter from DIN 6 to SCART, wired like this (the audio is taken from the audio out using a standard stereo 3.5'' jack): (taken from CPCwiki) If your TV does not have SCART, but composite video input, you must Either use a RGB to CVBS adapter (using for ...


12

As you can see from the schematic, the Armstrad uses a 6845 compatible display controller together with a custom-made Gate Array or ASIC for video output. The Gate Array also controls the screen modes using two bits of a register. We'll never know exactly what happens until someone reverse engineers the Gate Array, and while it has been decapped and ...


11

Secure? No, but much more so than protected BASIC programmes on tape, which merely had a single field set in the tape header that triggered the run once then NEW behaviour. It would definitely have slowed down most bedroom crackers, but if you had a sector editor, a printer and a good eye for detail, you could probably work it out quite quickly. As Ken has ...


11

Especially for writing the sound registers, it is advisable to use the built-in routines. According to the Schneider CPC firmware guide, the reason is the following: The CPC keyboard is directly connected to the AY chip - Thus, the keyboard service routine (which runs as an interrupt service routine) is accessing the AY ports directly. Accessing the sound ...


9

Considering how much of a rush job Locomotive BASIC was, it's remarkably good. But it's not perfect. Sinclair BASIC has one powerful keyword that Locomotive BASIC lacks: VAL. Sure, Locomotive BASIC has a VAL() function, but Sinclair's one is a function evaluator: 10 FOR X=-5 TO 5 20 PRINT X,VAL ("X * X") 30 NEXT X This would fail on an Amstrad CPC, but on ...


7

The fundamental issue with scrolling is that, unless your hardware does it for you, it involves moving around the contents of your whole video memory. In other words, scrolling is the type of video programming task that is mainly limited by your system's fillrate. And, unfortunately, the fillrates of the majority of retro platforms are not particularly good. ...


7

As stated, mode 3 is an unofficial mode and thus a side effect of hardware implementation, so the circuit is designed to handle only three modes (bit values 00, 01 and 10). This means that bit combination 11 is interpreted as some other combination of bits. From the list of modes' features it looks like there are three circuits that read video mode value: ...


7

I used the dsk2cdt tool to convert a .dsk image to a .cdt tape file. I can then play this tape file via an app (or convert it to audio data) and use a standard Amstrad tape cable to play the audio out to the 6128. I place a blank or erasable disk in the 6128, and then type |tape and run" Then I start the tape audio playing, which will load a boot program ...


7

I've written various programs that may help, if the DSK files don't make use of copy protection. If you can get files onto the +3 via the ZXMMC, you can use DU54 at http://www.seasip.info/Cpm/software/amstrad.html to write unprotected disk images to disk (or vice versa). It may be easier to unpack DU54.PMA within a CP/M emulator and just transfer the +3 ...


6

The Amstrad CPC was not slow at scrolling. Hardware scrolling as originally intended Ever since the Amstrad CPC was released, even BASIC programs could use vertical hardware scrolling of the whole screen by just printing text past the bottom line. It is true, though, that when used in the simplest way, the granularity of the hardware scrolling is a bit ...


6

There's another version I found online, but it's the DOS version. In that version, it only used the first three letters. Typing JOYOUS CELEBRATION would be understood as JOYSTICK. The DOS version, however, is different than the CPC version. While the source needs to be analyzed to get the actual algorithm (I think they rolled their own), it is possible to ...


6

The two machines had very different video memory layouts. The Spectrum had only 6144 bytes of video bitmap, plus 768 bytes of colour attributes for it. The bitmap was monochrome, but one could set foreground and background colours for 8x8 pixel blocks. The Amstrad had much more video memory, at 16384 bytes, and it was a "proper" colour bitmap, with two, ...


6

I'm not familiar with that system, but if users had the ability to protect their own files, then no it was not secure. If you can protect your own files (with known contents) then you have easy access to both the protected and unprotected file. XOR has always been a very common encryption method, so it would have been natural for a curious individual to ...


4

No, it wasn't considered really secure. In fact several programs existed at the time, including small "type-ins" available in magazines for removing that exact protection. There are some of them listed in the CPCWiki, which are no longer than 3 lines of BASIC (well, sort of) code. I'm not entirely sure when the first such program appeared on a magazine, but ...


3

Was it Robot Odyssey? This fulfills most of the criteria in your question except that Robot Odyssey was not isometric - or at least I have never seen an isometric version. It required you to program a robot in advance to solve room challenges and it was an 8-bit game in the 8-bit era. Here's a video of the game on the Apple //.


3

(sorry, this is not really an answer, but I cannot post comments yet) Given the constraints you have, it seems difficult. I do not know about the Spectrum side of it, but I did use a homemade parallel cable back in the days: http://cpctech.cpc-live.com/docs/mods/parallel.html This being said, you would still need a parallel port on your PC, a DOS/FreeDOS ...


3

Without having the source code, it is obviously a bit hard to judge, but let's have a shot at it. There are various possibilities to "guess what the player meant": Levenshtein distance, as you said - Possible, but probably a bit heavy for an 8-bit micro and (only) a command line interpreter - Also maybe a bit oversize for a fixed set of strings to match ...


3

Wanderer 3D was not with glasses on the Amstrad. Could it be Relief Action from Loriciel? (http://cpcrulez.fr/GamesTest/relief_action.htm)


3

My best mental reverse engineering of the constraints applied to the CPC bus, based on reading alone, is that it has a period of four cycles. Disclaimer: I'm not much of an electronics person, just an avid schematic reader as an offshoot of emulator authorship. The Z80's WAIT, which is the recipient of the gate array's READY is signalled for three out of ...


3

It sounds like you are probably referring to the 1984 release of Chipwits. It was originally released for the Macintosh, and was ported to the Apple ][ and Commodore 64.


2

Something to consider is the length of the keys. 13 plus 11 bytes gives 192 bits, while 128 bytes is 1024 bits, so this scheme isn't even one fifth as secure as using 128 unrelated bytes. If someone had access only to the encrypted files, the repeating nature of the keys would give an advantage as it adds a pattern that can be detected. The entropy of the ...


1

I would guess you mean Paradroid. This game was originally written for the Commodore C64 and published through Hewson Consultants. Here's a video. The game was (at least on the C64) not isometric, but rather had a somewhat 3D-enhanced birds-eye view and had you program robots to regain control over an alien-infected spaceship. The game was ported to a ...


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