A Bird’s Eye View…

Sharing a map from the game!

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Holiday Updates

Working hard on this! I’ve been doing a lot of new things in preparation for the game itself. Here are some of the highlights:

No Demo

I decided that I’m not going to release a demo.

My reason? A demo provides an artificial milestone for completion. Just get the demo working and you’re good! The problem is, the demo doesn’t contain or encompass all the game has to offer. So you’re not really finishing anything other than a demo if you aim that way.

This means I’m focused on ALL the content in the game, not just for a very small part of it. This helps me figure out how much space I’m really using for everything as well as what kind of changes I’ll need to make to the engine to accommodate specific plot points.

Content Generation

I’ve had the story of the CRPG in my head for a number of years now… some of it has undergone revisions in my head, but for the most part I knew how I wanted it to end. It was all the middle stuff I wasn’t sure of. ūüôā

So I sat down and started plotting out the various quest threads and stories for each region, and writing up the dialogue that would be needed. This has been very useful because it’s helped me identify new requirements for the engine, and helped me to flesh out certain areas.

One thing I wanted to really accomplish was to create a world you can believe in. If you play either of the first two Ultima games, you really don’t feel like they’re real worlds. They generally feel more like an amusement park. It’s strange that later games (like Ultima IX) actually regressed to that state.

Ultima III was the first in the series to really try and make it more like a real place, and it partially succeeded. The main problem was that there were still many towns and places that felt like “throw-in” material just to give you another place to go and buy stuff at, or find the ONE NPC in town that had something useful to say. The fact that the manuals didn’t even define the regions of the map as distinct places just reinforced it; you could literally redo the entire map of the game and move everything around and it wouldn’t matter.

So as I’ve been creating places and towns, I’ve really tried to think about the history and inject some interesting content and material to make it feel more like a real fantasy world. I’ve even made sure that the names of towns feel “fitting” for the region.

Elevated Maps

I’ve added map elevation to the game, which should help give the map viewing some depth, literally. ūüôā The idea that you can see over a forest if you get to a high point is very appealing! I had a kilobyte of RAM to spare to store up to 4 elevation levels. I had to completely re-write my map editor to accommodate adding elevation, and I also added light mapping to it as well.

My only concern, and it’s one I haven’t had a chance to fully test yet, is how it will impact the map view generation. In truth, areas that are over/under your elevation are MUCH simpler to calculate, they are either fully visible or not visible at all. But adding that extra bit of calculation to do may slow things down too much, I’ll have to see.

Graphics Crunch

I’ve had multiple character sets in the game for quite some time. As I’ve been focused more on finishing the primary engine, they’ve remained largely the same for a couple years now. Eventually I ended up with eight separate sets:

  1. World
  2. Town
  3. Castle/Keep
  4. Cavern
  5. Building/Interiors
  6. Dungeons
  7. Stat Screen
  8. Special (Non-disclosure on this one for now…)

Not long ago, I was looking at my Castle set and realized that I was largely using it for cosmetic purposes. So I decided to eliminate it and use building interiors for anything of the sort.

Recently, I started to try and draw out some dungeon maps, using some of my characters. I had planned to use tiles to create a false 2D isometric perspective; walls would appear to have top edges and slant down to the ground. The problem though, was that this proved incredibly time-consuming on the maps to draw, plus the walls were at odds with pretty much every other tile in the game.

So I decided to “crunch” my wall tiles down, using only a single tile. It’s much more simple and reminds me more of a BASIC game, but it also means I can consolidate my graphics into tighter sets. The only walls I kept was cavern walls; caverns I wanted to have some smoother edging in places, so it has five tiles.

So my new sets are:

  1. World
  2. Town
  3. Building/interior
  4. Cavern/Dungeon
  5. Stat Screen
  6. Special

One advantage this also offers is that maps can be less homogeneous; caverns and dungeons can freely break into one another in a much cooler fashion, where before they were either all one or the other.

My biggest challenge right now is figuring out how to portray elevation in a believable way that isn’t too confusing. I need to use a separator graphic of some kind to indicate an elevation change but also block the player from just moving up freely. Still working on this…

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Bullet points

Another five months, another sporadic update… ūüôā Been busy with various things; my girlfriend and I completed our living room decor this weekend and it is beautiful! If only my office was that clean and zen…

After spending some time working in C# on a transaction parser, I went back to the assembly code to actually implement the transaction code itself. This was important because I suspected, correctly, that the act of actually writing out the implementation would help determine what transactions I needed.

For example, my original plan had a transaction code that would alter any byte/word value in the game’s data arrays. This meant tracking size, operation type, index, whether or not subtraction would go below zero, not allow below zero, etc. But I realized it burning up too much code space to do a single simple operation.

Instead I focused on making transaction codes for specific use cases. Because training points are earned by all players at once, I just wrote a code to do that and that alone, rather than engineer a solution that would do it for anything anywhere.

Writing up transactions also revealed I had a lot of “dead” code from older implementations lurking about. Removing these feels good as it’s cleaning up the codebase and freeing up memory. I have just under 5k of space left which looks like it will be enough to finish it!

I came up with a new idea as well; I’m adding gambling as an option to the game. Certain places will have a gambling sub-game, involving dice rolls. I’m a big fan of the CRPG Addict, and he’s noted that games to win money are useful for bypassing tedious monster fighting in games. Given I don’t want the game to focus solely on combat, it seems like a nice idea to have the option to earn money in other ways.

Right now, I’m working on buying and selling items. I’ve hit a particularly complicated and infuriating snag, which is ammunition. I decided to make the item # for ammunition types reflect the count of ammunition awhile ago, because I didn’t want to maintain separate counts of items for everything. This “special case” though is causing major headaches… I can’t just consider the number of items in a backpack as an indicator of fullness where ammunition is concerned, because it should add to an existing item… IF it’s in there. Plus I have to display the cost on screen a little differently, showing the number of ammunition you buy for the given amount. So more special casing, argh! For selling items, I’m not even going to allow you to sell ammunition back for money, it’s just too complicated…

The good news is that after I’m done with all the transaction code, my next step is to prepare a baseline “demo” data package for test purposes, compile the code, fix bugs, and start testing the hell out of the engine to make sure everything works. Once that’s done, I can start actually WRITING the game in earnest. Getting closer and closer…

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Hammer and Screwdriver

What’s that title mean? That while you can drive nails and screw-in screws without tools, it’s a much longer and more exasperating process…

Tools for development are always needed. Besides my map and graphic editors, I have also wrote tools in Windows (in C# .NET) to handle some of the more automatable tasks. My text compression is an easy one; all I had to do recently to it was modify it to process a whole text fine line-by-line so that I could paste an entire block instead of one at a time.

But until I got VERY deep into design on transactions, I hadn’t realized that doing things by hand wasn’t going to cut it.

I’ve made one other decision; all NPC interaction is now tracked through transactions. This includes buying and selling items. As I was writing code, I realized it was just easier to have a single entry point for everything.

My original plan was to just hand-code the transactions myself, storing them in an Excel spreadsheet. I started to write out text files to describe each NPC and what they were doing. But as I did this, I realized how complicated it was getting. Plus, every small change would force me to re-do every single reference that was to an offset position. I would be reduced to gibbering insanity in a VERY short order if I had to do that. ūüôā

The transaction system is a word (2-byte) language that tells the game what each NPC does. For example, the code to display a message on screen is “!MSG” followed by a list of dialogue codes. Dialogue is structured as “0-5”, which means dialogue file 0, message 5. If I have several comma-separated messages, it loads and displays all of them in a block.

Here’s an example of a text file describing a sage in the first town:


?LOCAL_FLAG 0,Visited,NotVisited

!MSG 2-26,2-11
!BRANCH OptBuild

!PMSG Two,1-14,1-33

!OPTION 0-6,Q1,1-12,Q2
?QUEST_FLAG 1,OptBuild1,Select

!OPTION 0-7,Q3

!INPUT Select

!MSG 1-13,2-20

!MSG 2-25,2-18,1-6

!MSG 3-3

#Sage end

The # symbol is used to indicate the start and end of a transaction block. This allows me to add commentary in-between blocks if I need to; my intent is to have one large text file containing all of a disk’s transactions for processing.

When in a block, there are two kinds of commands, actions (!) and queries (?). Queries check values and branch to labels inside the transaction based on true/false conditions. Actions do things like display messages, alter data both in memory and on disk, start a battle, etc. Any line that has neither a ? or a ! is considered a label and gets added to a list to note it’s position in the transaction array. (For now I don’t have a “comment” symbol, but I could add one if I need to.)

Let’s go over it, shall we?

?LOCAL_FLAG 0,Visited,NotVisited

So first, we check a local flag. There are eight of them in a byte, so they are referred to by position, 0-7. Every NPC in the game has a local flag store of a byte, for tracking changes and states. #0 on all of them is being treated as the “visited” flag. This indicates whether or not this NPC has been interacted with before. This lets us have an NPC actually remember that the player has interacted with them already and respond as such. The first label after the flag number is the true case, and the second is the false case.

!MSG 2-26,2-11
!BRANCH OptBuild

If the player has not visited the Sage before, he has a few greeting messages. The visited flag is then set to 1, and we branch to the OptBuild label. After this, the player won’t see those messages again. When the player leaves the map, all the existing mob data is saved, including the new flag states, so returning later won’t restore them to blank.

!PMSG Two,1-14,1-33

If you have visited him already, he has a follow-up greeting. !PMSG is actually a “plural message” command. Given that the size of the party is entirely determined by the player, I wanted a message system that could deliver multiple messages based on how big the party is. The keyword “Two” indicates there are two variations, a single and a multiple. The first message is the singular party member version, the second message is the multiple party member version. There is also a “Three” version for cases where an NPC may say “You”, “Both of you” or “All of you”.

!OPTION 0-6,Q1,1-12,Q2
?QUEST_FLAG 1,OptBuild1,Select

!OPTION 0-7,Q3

The !OPTION command specifies a number of dialogues and branches that are choices for the player to make. These are added to a local memory stack for processing later. Two are added for two questions that are always available to ask. Then we check the status of a quest flag (#1) to see if it’s true or false. If a particular quest has been completed, we add a third option.

!INPUT Select

The !INPUT command pauses the dialogue and waits for the player to choose one of the pre-determined options.

!MSG 1-13,2-20

!MSG 2-25,2-18,1-6

!MSG 3-3

So for each option, the Sage has a different set of messages. It then waits for the player to press a key, then branches back to “Start”. This hard-coded label is always the beginning of the transaction.

#Sage end

And that’s the end of the transaction block. So I run my parser on it and I end up with this:

05 00 0E 04 0E 02 20 1A 20 0B 13 00 01 14 0F 00 10 0E 10 21 11 02 00 06 00 2A 10 0C 00 34 06 01 22 28 11 01 00 07 00 40 12 01 0E 02 10 0D 20 14 12 00 01 00 0E 03 20 19 20 12 10 06 12 00 01 00 0E 01 30 03 12 00 01 00

72 bytes, or 36 words, to define the entire transaction!

Transactions are all stored as 2-byte records in one large file per disk. Looking over my initial calculations of size for different things, I will end up with a couple thousand records per disk. If sizes remain at a consistent amount, I may also increase the record size and pad out some of them with zeroes for quicker load times. (I don’t think it should prove to be a particular problem; the TI disk controller loads an entire sector into VDP anyway so as long as transactions don’t cross sector lines it will remain fairly fast.)

Now I just need to write up the code to process the transactions and do all the displays… fun fun!


Posted in Coding, CRPG, Design, TI-99/4a | 3 Comments

Dragon Questing…

While working on my transaction stuff I’m also doing some research on the needs of the story that I’ve had on my mind for the last several years and what the engine needs to do to make it happen. But… It’s not all work. There’s some play too!

Recently I got an urge to re-play the old Dragon Warrior games on the classic NES. There were a few CRPG’s on the old Nintendo, but the two most well known were Dragon Warrior and Final Fantasy. I’ve already won the latter on the classic console (I still have the blister scars from buying 99 heal potions OVER AND OVER… stupid interface!) but I never played Dragon Warrior II to conclusion, only the first and third.

Why? Well… these games were NOT easy. The level and XP grinding you had to do was insane. The first game required you to sit and kill slimes, the weakest monster in the game, for around an hour before your character was leveled up enough to explore further than a few steps from the starting castle and town. If you died you lost half your gold, so exploring early was punished harshly. And you NEEDED money because all the best gear was incredibly expensive. Playing the original Dragon Warrior on the NES was more painful than fun.

Dragon Warrior II was a better game overall, offering a party of three characters and a much larger world to explore. You still had to grind hard-core though; many players took advantage of a small bug in the game to obtain a valuable item over and over again and sell it to make the money to buy the best gear. I didn’t win it back in the day primarily because I didn’t own it, I could only play a friend’s copy and I couldn’t borrow it long enough to win.

So I had an itch to play these old games, but at the moment, all my video game console stuff is still packed away… Plus, my general experience with the old games is that it would mean spending a LOT of time in front of the TV, doing the same repetitive things over and over, eventually muting the game so the music wouldn’t give me a headache…

Fortunately for me, there was a solution… the games have been released for the Android mobile platform! (Under their original name “Dragon Quest“) So I was able to purchase them cheaply on Google’s Playstore and download them for my tablet and phone.

Compared to the originals, the games have some differences, all to the good!

One, the graphics are WAY better. When they did the port, they actually used the Super Famicom graphics for a version that was only released in Japan. I don’t mind the original 8-bit graphics of the NES versions, but it’s nice to have an upgrade.

Two, the adaptations retain the the original “Athurian” language and some of the place names. Some of the mobile ports reverted entirely to the original Japanese, where the renowned hero “Erdrick” is named “Loto”. I’m relieved to have familiar names and places, although most of the towns in Dragon Quest II have different names. Spells have completely different names entirely; most of them have sound-effect style names like ‘Sizzle’, ‘Kazing’, and ‘Thwack’. Fortunately the mobile version interface helpfully tells you what each spell does so you know what it is.

The actual in game text is also much more loquacious, with a lot of style and nuance that was absent in the NES versions. This is partly because the old cartridges were very tight on memory, but also because Nintendo stripped out anything with religious overtones. This is very fascinating to me because the games have a VERY religious theme to them.

For example: the enemy in Dragon Quest II, Hargon, is actually a high priest and not a wizard. There’s a lot of discussion about how he has perverted his position against the Goddess, the “god” in the Dragon Quest universe. Instead of “Wizard Rings” to restore magic points, you have “Prayer Rings”. Magical power is directly associated with divine energy, and so forth… I actually find it really enriches the game and makes it much more fantasy-feeling.

Three, playing the games on my tablet is much more comfortable and easy than playing in front of a TV. I can move about, take it with me to different rooms, and I can even leave the game running and not have to save constantly!

Best of all… the games are much easier to play. The interface has been reworked to function very well on a touch-screen interface. The first Dragon Quest game has clearly doubled experience and quadrupled (!) gold so you can level up and advance MUCH faster.

Dragon Quest II is more subtle in the improvements, but they are there. If a targeted monster dies before a character attacks him, he switches his attack to another monster. I’m pretty sure a lot of the under-the-hood mechanics for determining hit chance and damage were tweaked as well, your characters seem much stronger and more capable than the NES version, where you always felt like you were one combat away from a TPK.

Advancement, particularly spells, don’t follow the original game. I was expecting to get the Firebane (or ‘Sizzle’) spell at level 18 with the mage/warrior character, and instead I didn’t get it until level 24 thereabouts! Curiously none of the walk-through’s note this discrepancy… Your priestess character also maxed out at level 35 in the original, but in this version I got her to 36 before I won the game.

The best aspect of these games, though, is that I can finally play ones that were never released in the U.S. I’m playing them through in order; I’m now on Dragon Quest III, and looking forward to moving into the ones that started a new story arc.

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Transacting Scripts

My focus remains on turning out a working and complete demo of the game… I’ve written a bunch of code I haven’t even had a chance to test yet. And I’m currently working on plotting out a long-neglected portion of the game; complex transactions with NPC’s.

I’m doing SOME stuff that isn’t entirely practical. For example, I’m finally working on finishing the title screen. I had always been stymied by the fact I didn’t really want to take the time to plot out the thing in a paint program. (ESPECIALLY in TI-Artist, which is incredibly painful to use for pixel plotting. Multi-color mode, blech!) I finally found a low-tech sneaky way to do it… Transcribe the character graphics myself by the naked eye into the bit patterns and hex-edit them into a Paint N’Print file. (Paint N’Print is my favorite editor; the zoom mode is perfect!) I can then colorize it later in the paint program.

So, about those transactions…

I decided early on not to have a text parser in the game. (Basically, a cursor which would allow you to enter key words.) My decision was based upon two things:

  1. Text parsers are a pain to implement and error check in assembly language
  2. Too much like Ultima

How can being like Ultima be bad? Well, Ultima IV is actually very simplistic; there is a maximum of 32 NPC’s in each town, and each one has a single 288 byte record to store all their conversations. (Except for special NPC’s like Lord British and Hawkwind, of course.) If you look, the actual depth of each character is shallow; each character only has two potential keywords beyond the baselines (name, job, health) and a single question and virtue that is affected by it. Ultima V is slightly more complicated with the day and night cycles and NPC schedules, but conversations are largely the same structure.

Also, there’s a certain degree of “I want this to be MY game, not just a copy of Ultima.” There’s been too poor-man copies of Ultima over the years (Gates of Delirium comes to mind…) and I want my game to stand out as something that is entirely itself.

Another aspect of my design is, I want the game world to CHANGE based on the player’s actions. All too many old CRPG’s have worlds that largely remain the same, even after the player has accomplished things. You save the town and they’re STILL talking about the danger?

So, there are two kinds of NPC’s in the game, simple and complex. The simple ones are much like the NPC’s in Ultima III; they have a single response they say and nothing more. There will also be map flags for each area so that if you have achieved certain goals, they say different things.

Complex NPC’s though, are another matter. For those, I’ve had to create my own little scripting language.

Essentially, each complex NPC has a set of local flags (one byte’s worth, one of which is always the “visited/revisited” flag) and a set of transaction records, each one word (16-bit) long. If the average length of these transactions ends up being a consistent size I may just convert them to longer records and live with a little wasted space.

Each word has a code indicating either an action or a query, with a variant amount of data after it. For example, it may check that a certain flag is set. If so, it moves to the appropriate spot in the transaction string using a positive/negative offset value, and continues transaction processing from there. It can display messages, set up options for the player to select from a list to determine a series of next results. And it can give money (or take it), items, or make changes to the party and player data as needed. A veritable transaction engine!

Here’s an example of how it may look:


IF Visited_Flag    (4)
    DISPLAY Intro (4)
    SET Visited_Flag (2)
    BRANCH Options (2)
    DISPLAY Revisit (4)
    BRANCH Options (2)
    OPTION Question_1, Question_2 (10)
    SELECT Option (2)
    IF Option_1
        DISPLAY Read_1, Read_2 (6)
        BRANCH OPEN (2)
    IF Option_2
        DISPLAY Take_1 (4)
        SET Quest_Item_0 (2)
        CLEAR Mob (12)
        END Transaction (2)

Total: 58 bytes (29 words)

In fact, as I was designing the system, I realized that I could use it to replace some things in game. For example, I originally had fountains as a stock object in game for dungeons and places, that would have variant effects upon you. But I’ve been leaning towards removing them as a more “gamey” object more appropriate to old-school first-person dungeon designs, and I realized that I didn’t even need to HAVE special code for them. I can just make a fountain a transaction if I still want one!

I did briefly consider integrating shopkeepers into the same transaction system, since it’s already going to be doing a lot of heavy lifting. I decided against it in the end, though, because with shopkeepers, I have much more predictable data structures. That will let me write much more streamlined code to handle the transactions for those.

The only pain point with this approach is that coding the actual scripts up is going to be a pain. Since all the offsets are going to be localized and fixed, that means they will need to be updated with any changes. I’m going to initially try and set up an Excel spreadsheet to store this for me so I can (hopefully) just copy out a clean hex string to paste, but we’ll see how it goes…

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Monstrously Complicated

So I decided to switch things up a notch, and move over into monster A.I.

Why? Well, the FX spell system is now definitely working, the only tasks remaining are to implement and test out each spell individually. This won’t actually take too long. The only real complicated bit left is the alteration spells that cause battlefield changes, like creating a wall of fire.

I’m more concerned right now with removing a lot of the short-cuts and implementing the full pipeline for combat. This means actually checking for victory conditions, determining treasure, and returning back to travel mode cleanly. And as part of that… monsters actually doing stuff!

So my original architecture for monsters was, well… very ambitious. I had four different intelligence levels, the highest of which would consider spell casting as a “high threat” and target that character specifically. Every monster would have “aggravation” counters to determine who pissed it off the most. Spells would include at least two offensive and defensive spells: a ranged attack, a close attack, a self defense and an ally defense. And finally every potential action a monster would take would be weighted on priority and the best one selected each turn.

Then I realized how much code space it would take up to implement all this. I currently have around 8k of space left for code, and I still have a LOT of other stuff to implement. Creating the simplest and easiest monster A.I. to start with and then adding to it and updating it later when all the major pieces are done makes a lot more sense.

Plus, on screen, all a player is going to see is a monster take a step towards them. All that cleverness will be invisible and undetectable. Is there really a difference between a monster making a ranged attack on a character because it was the most properly weighed action, or just at random?

Plus, I don’t really want the combats to take a long time. Playing Ultima IV made me realize that when you have an awkward interface and no way to skip a lot of things, the combat can really become a hassle. (Get into a battle with reapers. You’ll see what I mean.)

And finally, it’s very VERY possible to make the monster A.I. just too damn good. If monsters all target the character who just threw a fireball at them with ranged attacks, that character won’t be alive long. It’s a general truth in most computer games that it’s pretty easy to write artificial intelligence that’s TOO good. You want it fun and challenging, not bone-grinding difficult to impossible. (Unless you’re playing Wizardry of course…)

The new simplified A.I. is pretty simple. A monster finds the closest target enemy unit and either moves towards them, targets them with a ranged attack, or targets them (or their location) with a special attack/spell. The one thing I need to add in and figure out is when a monster should use a close attack. A dragon breathing fire, for example, will want to have the player very close, and preferably none of its companions in the way!

I’m in a frame of mind now that before I release another demo, I should have as much of the game implemented as possible. That means not just the A.I. but also all the town services and everything needed to actually play the game. I really want to FINISH the game engine and start focusing in earnest on actually writing the story and designing the game itself.

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Burn baby burn!

And the spell is done!

It’s amazing how much effort went into getting only a few seconds of action on the screen, but wow it’s beautiful!

As part of my efforts, I also am making a few changes to how orientation is determined… I originally was going to have it random, but I realized that would be a disconnection from on screen, where you may move your party into a mob, or get attacked in turn from a particular direction. So I altered things a bit so the direction is determined that way.

Another aspect is the ambush. I realized belatedly that the Ultima mob methodology (where you see them and they move towards you) doesn’t work with ambushes because, well, you SEE them. How can they surprise you? So I’m redesigning it so that at times, hidden monsters are placed on the map and if you trigger them, it’s an ambush situation.

Work continues on the next set of spell effects, which includes a cone effect and a wall effect… I’ll want to test out all 64 spells individually to make sure they’re all satisfactory.

Posted in CRPG, Design, TI-99/4a, Video | 2 Comments

Making Room and Untangling Things

Happy 2015 everyone!

Yeesh… I’ve been working on this project for 10 years now… I seriously need to just get it done!

I’ve been pretty busy since late December moving into the new home, and getting things organized and put away. You accumulate a lot of stuff when you stay in one place awhile… and the fact I’m a bit of a pack rat doesn’t help matters. I found to my surprise that I had seven, SEVEN, TI-99/4a consoles in my garage. I’m not sure how that happened! I don’t need that many, really two is enough, so I’ll be looking to find new homes for some vintage hardware.

On the CRPG side of things, digging back into my code base meant figuring out where I had left off… as part of that, I also started to wonder how much more space I had for the game and when I’d need to start moving code into different areas.

A little hardware background first…

The TI-99/4a has a 16-bit addressing space, so it can address 64k of memory maximum. Most of this isn’t RAM; a lot of the address space is consumed by ROM’s, cartridge drivers, and other system peripherals. The console itself actually only has 256 bytes (!) of actual CPU RAM.

The only other RAM in the system is the 16K used by the video display processor. This RAM is not included in the addressing; there’s a memory-mapped ports in that very small CPU space (nicknamed “the scratchpad”) to read and write bytes to and from VDP memory. Yes, it is an eclectic computer indeed…

A fully upgraded TI-99/4a includes a memory expansion card, which adds 32k to the system. It adds 8k in one spot of memory (called “low memory”) and 24k in another (called “high memory”). When you wrote assembly language programs with the Editor/Assembler, you typically only have the 24k available, because the loaders used to load your program occupy the low memory, along with some other utilities. There IS space there, around 6k worth, but it’s tricky to get into.

Most assembly programmers on the TI write their programs to load as “memory image files”, which are just raw assembly code loaded as 8k segments directly into memory, chained together with a common file name structure. In order to convert your assembled program INTO memory image files, you used a a utility that occupied the low RAM. Which meant you still couldn’t quite use that whole space.

My solution to this problem is to reserve the entire low memory section as pure RAM for the program. I’m actually using that much RAM (or more) for the game; the maps alone consume half of it. After the program finishes loading, the entire space of memory is mine to use as I see fit, and I don’t have to worry about loaders.

But… my program is going to exceed 24k in size. I’ve known this for awhile, so I planned for it by obtaining a handy cartridge called the Super Cart. It’s basically an Editor/Assembler cartridge, but with 8K of RAM at the cartridge port address. This extra space will be enough to finish the game easily, and for those users who want to run on an actual TI, the cartridges aren’t hard to come by.

Figuring out how to create the memory image files for this proved to be a challenge, though. There are compiler directives to redirect code into different addresses, which I used, but I found out that I was unable to use any utility, in the emulator or on the TI itself, to actually create the files!

My final solution is a bit of a hack… literally. I do a memory dump out of the emulator after fully loading the assembled file into memory. I then hand-create the memory image files and copy and paste the data from the dump into files using a hex editor. It’s a bit slower than the old method, but it works, and now I have freed up plenty of space in high memory to finish the job!

On the CRPG code itself, I’m working to get at least ONE spell, fireball, working. The effect on screen should be spectacular, a ball of flame streaking towards a location and exploding, sending clouds of fire and dust in a slow spiral outwards. Implementing this has proven to be trickier than expected though…

Aside from writing the code to achieve the effect, I’ve discovered that my code to determine attack results with melee and ranged weapons got somewhat mixed into my actual effects code. I need to unravel it and clearly separate the effects on screen from the actual logic to determine WHAT effects to show and when… This also means I’ll have to do regression testing of melee and ranged combat when I’m finished…

My latest code effort was rather amusing… instead of a fireball streaking out to the targeted location, a fireball flew towards another party member and struck them causing damage! Not QUITE what I was going for…


Posted in Coding, CRPG, Design, Personal, TI-99/4a | 2 Comments


Hello all! Wow, it’s been a year since I last updated… it’s been a busy one!

I had some major big things happen this year. I left my current job and got a new much better one. I started commuting by bus instead of driving, which proved to be far less of a problem than I thought it would be. This lead to my next move… to buy a house!

I’ve lived in a townhouse condo for nearly 5 years, and the time has come to move on to better accommodations! In particular, a place that is much closer to my girlfriend and that will be much easier for her to move into with me. ūüôā Also, a LOT more storage space for all the things I love, like vintage computers, gaming books, etc.

So, for the rest of this year, I’ll be working hard at packing up stuff, cleaning out things I don’t need, and getting relocated to my new home! Then I have to clean and get my condo in shape to sell, very quickly… the market right now is very good for it, but that’s a bit of anxiety that needs to be quelled as quickly as possible.

After I get settled in, I’ll have time to look at my programming projects anew…

I have worked on the CRPG off and on over this year, but made no significant updates I could share… when I last left off I was trying to get spells working in combat, which will open up a HUGE amount of testing work to do.

I’ve also been lured by the ease of Extended BASIC into other TI projects as well…

I completed a conversion of an old favorite TRS-80 Color Computer game, “Space Trek” to the TI, and have several other small coding projects in the works, including re-creating Aardvark Software’s “Quest” and “Wizard’s Tower” titles on the TI (which were commercially released but copies are impossible to find now) and my own personal project, “Kingdoms”, a turn-based strategy game similar to the titles put out by Not-Polyoptics.

See you next year from our new home!

Posted in Blog, CRPG, Personal | 2 Comments