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Exidy Sorcerer II Questions

I would also be interested, using Eagle free (the only designer I'm used to) it's easy to create PCBs until 10x10cm. I'm not sure about creating Gerber files tho :-(

The Sorcerer Monitor has an input redirection function. If you OCR the source you could then "print" it from a PC into Exidy BASIC through the serial or parallel port and then CSAVE it.
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I'll check MESS. Maybe I could end up with an easy solution for this...
 
I have added Kilopede, Space Invaders, and Galaxians to the tape sim. I had to remap the keyboard in all three. I also added Amazing Maze but cannot find the key input routine. What keys do you use to play it?
 
I couldn't get Amazing Maze to do anything either. I banged on just about every key and eventually got it to break out of the program and it said something about CP/M! Let me know if you figure it out.

BTW Galaxians, Defender, Space Attacker, and Asteroids all support sound!
 
There are even versions 1.12 and 1.2 (not official ones tho, programmed by someone called Pete). Mine has 1.3, seems to be an evolved version programmed in Holland when the Sorcerer was acquired by Compudata.
The firsts versions seems to be pretty easy to burn as a straight replacement of the ROM.
 
I thought you had to do something to make the Sorcerer recognize EPROMs instead of ROMs? I swear I read that somewhere.
 
But I also read in one of those newsletters that the process is wrong. Unfortunately they didn't say what the correct process was (that was the next letter which we don't have).
 
Has anyone successfully run Super Star Trek? When I run it, it only accepts level 2, draws the screen, prints something about Capella 1, then stops with ?SN ERROR LINE 164. It lists OK. What's up with that?
 
A syntax error in a line looking good?, if the line is really correct looks like a memory problem. Maybe the listing is being allocated in a different area due your 56K mod...
 
tempest said:
We figured it out. The issue was twofold: a bad cap on the 12v line and the dip switches were set incorrectly. Apparently the Sorcerer II tech manual is wrong and the text on the motherboard is correct. The video issue was most likely due to the sorcerer using the video memory for regular memory because it couldn't detect any of the installed memory..
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The original Macintosh could do something like that. If you made a disk image or duplicated a floppy using Disk Copy on a Mac 128k, it'd use the video buffer as temporary storage because it doesn't have enough memory for copying. :p So you'd get weird screen artifacts on the lower half of the CRT while it was doing that.
 
Except I didn't relocate the BASIC, I just load it into the upper 8K of 56K (C000-DFFF), where it would be in ROM. Maybe there's a bug that overwrites in that range? Or maybe the image has errors? I have seen other odd behaviors even in small BASIC programs I type in. Hmm.
 
I'd try it but not all of us are lucky to have access to BASIC. :)

If you look at that online emulator I linked to a while back it had a working Star Trek on it (I played with it for a bit). Maybe you can get the rom image from there?
 
Tried 2 other BASICs, 1.01 and rev B. 1.01 behaved exactly the same. Rev B would not accept theCLOAD command - it immediately says READY without trying to load. :(
 
jltursan said:
56K?, that explains all! :-D. Do you have an schematic of what is needed?
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Yes, attached is a schematic for the 56K mod. I don't recommend it though for these vintage machines. It's a drastic mod with cuts to the DRAM +12 and -5 V lines, replacement of 16K DRAMs with 64K chips, removal of 3 LSTTL chips, and a lot of solder. The II with 48K would not benefit much anyway, and my circuit doesn't switch to 48K when a cart is plugged in (notice that my board has no cart connector). A Sorcerer I could be upgraded to 48K (or 56K) much more easily by adding SRAM.

ExRAM56K.jpg
 
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ClausB said:
Good news, everyone!

I may have found the cause of the tearing / jitter during screen access. I looked at the HSYNC circuit on an oscilloscope and saw that, during screen RAM accesses (Monitor command TE FE00 FF00), there is a one cycle jitter in timing between HSYNC pulses. That's one cycle of the 6 MHz clock, which is the time it takes for two pixels to clock out.

It appears to be a bug in Exidy's original circuit. The low bit of the horizontal counter gets loaded from the output of a flipflop which clocks the E256 signal. The problem is that, during screen access, that flipflop gets set in order to briefly blank the pixels. That's by design, and it's why we see the brief, short, black lines. But a side effect is that, if the access happens when the counter reloads, the wrong value gets loaded into the counter, causing a short (by 2 pixels) scan line, and horizontal jitter on a CRT monitor. When I lifted IC3A pin 3, the jitter on the scope went away. I have not yet looked at it on a CRT but it really seems like the culprit.

Presently, IC3A (IC22A on the II) pin 3 connects to IC7B (IC17A on the II) pin 9. The fix will be to connect it to IC7B (IC17A on the II) pin 12 instead.

I'll post again after checking the fix on a CRT.
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Attached is a schematic of the mod. It has been tested on 2 Sorcerers, a I and a II.

ExJitFix.jpg
 
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Nice, thanks!

Indeed, the 56KB mod is a bit intrusive; recently I've found the Exidy BASIC cartridge, all in all a great find, so at least I can try with all that BASIC listings out there. If the 56KB are not switchable I've a problem now.

My II has already a lot of mods including the jitter mod and the 64Kx1 DRAMs (in fact I'm using 256Kx1 ICs) to get the full 48KB. I find interesting the SRAM idea tho, definitely a single 64K SRAM would be much better than two dozens of DRAM ICs generating heat and draining power.

Of course the lack of a massive storage solution it's still the biggest drawback of the machine :-(
 
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