Retrochallenge Winter Warmup 2011 Entry

Well here it is, the first installment of Silent Running, a text adventure created using Inform.  The initial idea was to create something that would run on my Epson PX-8 which is a CP/M based machine. The first speed bump was locating a Z-machine interpreter for CP/M until it was pointed out to me that as I had the original Zork games for CP/M I had a suitable interpreter.

The Zork games typically came as two files, for instance, and Zork1.dat, the .com file being the interpreter and the .dat file the story file.  The interpreter supports version 3 story files and if you create a compatible story file you can rename it Zork1.dat then run and your game will load and run.

Needing to create version 3 story files I opted for Inform 5 as the compiler and was of course free to write the source code in any suitable text editor.  Thus development has taken place on a variety of machines including the Atari Portfolio, Epson PX-8, Epson Equity LT and some more modern machines.  I had hoped to compile the code on the Equity but I still haven’t had any success.

The game itself is heavily influenced in tone by Snowball from Level 9 which remains my fondest memory of text adventuring, that and Melbourne House’s The Hobbit.  I would estimate that I’ve completed about a quarter of what I’d hoped, therefore there are a number of elements within the game that may currently seem like red herrings.  The current goal is to achieve access to the biodome area of the freighter.

There will of course be many bugs, not the crash your system type, but responses to player input that are not catered for and the like.  Once you’re in the world creating it it’s difficult to jump outside and imagine how others are going to interact with it, reports would be welcome.

I’ve been quite absorbed by this process which has been enjoyable although it has meant I haven’t had as much time to keep up with all the other entries as I’d have liked and I’m looking forward to doing that now.

You’ll need an interpreter should you wish to try the game, you should be able to find one here:-

Link to Interpreters

Download Silent Running Story File

If like me you need an interpreter for CP/M you can download Zork and the included interpreter here.

Guybrush Threepwood in CGA

No progress on the Silent Running adventure for a couple of days.  I got bogged down in trying to resolve a particular issue, realised it was time to walk away and come back fresh which hopefully I’ll do today or tomorrow.

Instead I’ve been messing around with the Equity, trying to understand what it’s capable of.  My first experience with a PC as opposed to machines such as the Amiga and Commodore 64 was a Pentium 90 based machine with Windows 3.1, so the pre Pentium days passed me by.

I’ve been trying to compile the code I have written so far with the Equity with no luck as yet.  As a point of interest the code compiles on a Core 2 Quad essentially instantaneously.  On a Pentium 166 it takes a few seconds.  On the Equity it’s taking around 4 minutes before failing on a specific library issue.  I need to try the Minform library I mentioned in an earlier post next.

I also wanted to see what games would run on the Equity and found an early version of a Secret of Monkey Island demo which loads and runs.  I was never really aware of the limited graphics abilities of the early PC’s having been spoilt by the abilities of the Amiga and its custom chips, it’s pretty basic stuff as I’m discovering.

The Equity has two option slots, one is currently occupied by the hard drive controller card and I believe the only other card produced specifically for the option slots by Epson was a modem card.  Somewhat bizarrely one just came up on Ebay, unused, and new in the box so I snapped that up (only bidder) and it’s on its way.

Monkey Island Demo

Epson Equity LT

I’ve been trying to settle on one platform for the development of my Retrochallenge Winter Warmup project, a text adventure for my (and other) CP/M based Epson PX-8.  Not that long ago I acquired an Epson Equity LT laptop circa 1989.

The unit itself is in remarkable condition cosmetically and runs quite happily when booted into DOS using the internal 3.5″ floppy drive.  However when originally attempting to format the internal hard drive the format would progress normally to about cylinder 158 or so whereupon it would slow to a snail’s pace taking roughly 20 minutes per cylinder from there on.

Given that I don’t really need 20MB of disk space for my project I got the unit out again and used fdisk to create a DOS partition that only used the first 156 cylinders or around 4-5 MB of the drive.  The format progressed successfully and I installed MS DOS 3.2 from the original Epson disk that came with the unit.

I have a fondness for Epson design from this era and I think it’s a great looking unit.  The screen is pretty good and I like the keyboard.  The main specifications are:-

CPU – NEC V30 (μPD70116) CMOS microprocessor, compatible with Intel 8086 runing at the same speed as the 8086 but 10% – 30% faster. (DIP switch on front on unit allows switching between 4.77 & 10mhz speed)

RAM – 640k

Floppy Drive – μPD765A controller supporting four 360Kbyte or 720Kbyte 3.5″ disks.

Hard Disk – JVC JD-3824R RLL type, 21.44 Mbytes 95mm diam.

Option Slots – Two 8bit expansion slots (Modem on the way from US)

Graphics – Built in LCD and RGB output for external monitor CGA standard up to 8 grey levels.

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