Any C implementation for that era (1979) of micros is a pretty good find, IMHO. Although I'd reccomend finding a C for the PC class, post 8086, (1985+) if what you want to learn is software. John A.

John Allain wrote: A lot of 'free' 8086 C compilers are now out for the with the demise of DOS. http://www.thefreecountry.com/compilers/cpp.shtml

And thusly Ron Hudson spake: http://www.cc65.org There is a port for the Apple II... Cheers, Bryan

Anybody know how to do serial port access to a "Text Lite" LED text display? I have about three feet of one of them here. John A. and in 30 minutes it becomes a bunch of matrix displays semi-kidding

On Tue, Apr 27, 2004 at 02:32:30PM -0700, Zane H. Healy wrote: Hmm... sounds like something fun to play with. That's a good project (I'm one of the contributors - for the PIC-an-LCD driver, among other things)... still active, too. -ethan -- Ethan Dicks, A-130-S Current South Pole Weather at 28-Apr-2004 07:40 Z South Pole Station PSC 468 Box 400 Temp -74.3 F (-59.1 C) Windchill -118.5 F (-83.7 C) APO AP 96598 Wind 9.80 kts Grid 073 Barometer 677.4 mb (10723. ft) Ethan.Dicks(a)amanda.spole.gov http://penguincentral.com/penguincentral.html

On Wed, Apr 28, 2004 at 08:34:37AM -0400, John Boffemmyer IV wrote: Glad to answer questions. My personal focus on the project is drivers for interesting hardware (non-Hitachi-compatible VFDs, the PIC-an-LCD interface to parallel LCDs, etc.) Down here, I'm using PalmOrb and a Palm Vx for my display (no reason to ship down two things when one will do). I took a stab at a Solaris port of LCDProc a few years back (1998?) but at the time, I could only get about 60% of the stats that Linux provides in the /proc filesystem, so I abandoned the effort in favor of someone else who was adapting, I think, libpcap. Not too bad (see below)... winds over 20 knots are unfun. We set some records earlier this month. Fortunately, there's an inverse relationship between the temp and the winds (so it's anywhere from -35F to -55F when it's that windy. Winds are normally calm below -65F). -ethan -- Ethan Dicks, A-130-S Current South Pole Weather at 29-Apr-2004 01:50 Z South Pole Station PSC 468 Box 400 Temp -80.4 F (-62.5 C) Windchill -119.9 F (-84.40 C) APO AP 96598 Wind 8.5 kts Grid 060 Barometer 679.4 mb (10647. ft) Ethan.Dicks(a)amanda.spole.gov http://penguincentral.com/penguincentral.html

It's a "text lite mm500", made in Ireland apparently for a german company (www.textlite.de I think). Seems to want about 6V 1A. The serial port is a 1/8" phono-stereo jack so I'm tempted to try the cord for my digital cam on it, a better than 1:6 chance of the connections being right. There are three other ports: synch in/out and a 14 pin IDC. I think the synchs allow scrolling across multiple lines of display. If you your serial port is a 1/8" I'd be interested in the signal assignments. John A.

No clue. I do have a O'Scope handy, but a rather useseless brain as regards to applying said O'Scope. An instruction or two would help. Am I looking for 5v vs 15v signals? John A.

The first thing I would do is to trace where the connections from the serial port go. One of them, almost certainly the sleeve, will go to ground. If the other 2 go to level shifter ICs (MAX272, 1488/1489, etc) then it's RS232. If they go directly to the pins of a microcontroller or a TTL chip, then it's TTL levels. If it's something else, come back here with what you've found. Also, measure the DC voltage (voltmeter, DMM) between the 2 signal connections anf ground. If one of them is at a -ve voltage, then it's almost certainly RS232. -tony

On Friday 30 April 2004 18:07, John Allain wrote: -ve : negative voltage. As opposed to +ve :)

John Allain wrote: Not necessarily: you can convert the voltage levels with just a few discrete components. Mostly in such cases the receiving voltages are used to charge a capacitor that delivers the negative voltage for sending data. In that case there must be a diode somewhere in the neighbourhood as well. Bert

Really dirty trick, used in a lot of commercial modems : Feed the RS232 signal through a resistor in to a 74HC or 74HCT input. Use the protection diodes of the chip to clamp the signal. Preferably add a pull up/down resistor as well. No, I don't like it either! That, actually, is the standard 6 pin DIN connector. Doens't that depend on the Laptop. I have an idea (without proof, and the service manual/schematics are upstairs) that the HP110 and Portable+ gave out rather more than +/-5V on the RS232 port. One other trap. Almost all RS232 receivers (including the 1-transistor one) invert the signal -- a +ve voltage on the input gives a TTL 0 on the output. So you may need to put an inverter between your TTL serial output and the device. Admission time : I have once used a 74LS04 as an 'RS232 driver'. It didn't meet the spec at all, of course, but since I knew the characteristics of the only port I was going to use the device with, it worked. I also once used a 1489 (qwuad RS232 receiver -- converts RS232 to TTL levels) as a driver too -- A TTL signal will meet the input spec of that device, and the output will also work into the input of another 1489. Meant I could use 1 chip from the junk box to link my TTL design to an RS232 port. No way would I do something like this in a device that was going out to somebody else, or one which I was going to use on a variety of machines. -tony

On Tue, 27 Apr 2004 12:22:43 -0600 ben franchuk <bfranchuk(a)jetnet.ab.ca> wrote: Agreed, but sometimes it's fun to dredge around in the past. We do that here, don't we? I was messing around writing code with my copy of Aztec C for DOS last fall for awhile. I have the full set with disks and manuals, and it wasn't hard to get it going on an old laptop. And it's nice to have archaic tools that you can write code to run on really old equipment, i.e. DOS 1.0 machines.

On Tue, 27 Apr 2004, Ron Hudson wrote: I think learning assembly language is the best way to go then. It's not difficult, and the experience will be much more rewarding than trying to use Aztech C on the Apple ][. Integer BASIC wouldn't give you any advantages here. Maybe. Copy all the files from the 5.25" disks to 3.5" disks. I'm not sure if Aztech will know what's going on though. Your best bet is to find a cheap hard drive that you can copy everything to. This guy made an IDE interface for the Apple ][: http://s.guillard.free.fr/Apple2IDE/Apple2IDE.htm He has the plans available for free and the parts cost less than $15 (according to him). -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

On Wed, 28 Apr 2004, David Holland wrote: Ah yes, very cool. There was also a guy who built an Apple ][ card with a laptop IDE harddrive on-board (I believe) but I couldn't locate his site. Wow, cool! I didn't realize these Perl libraries were out there. -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

It was thus said that the Great Tony Duell once stated: C is a pretty poor match to the 6502 though---not enough stack space (one page) and anything you get out of the compiler will probably be worse than what you can do by hand in assembly. The 6809 is geared more towards C (and higher level languages in general) than the 6502. Compilers for the 8080 (Z80) may produce mediocre code. What Tony said. _The C Programming Language_ by K&R is *the best* book on learning C, period. It's one of two books on C that I have and I still use it to this day (having started with C in 1990) even if it is only Appendix B I use (Standard C Library). The other C book I have (and recommend) is _The Standard C Library_ by P. J. Plauger. K&R teaches you C, while Plauger teaches you the Standard C Library, and why it is the way it is (and gives you a sample implementation of said library). -spc (Oh wait ... I lied. I have three C books---the third being Numerical Recipies in C)

It was thus said that the Great Ethan Dicks once stated: Yes to the above. The 6809 has the following: A - 8bit accumulator B - 8bit accumulator DP - 8bit Direct Page [1] CC - 8bit condition code D - 16bit accumulator (reg A MSB, reg B LSB) X - 16bit index Y - 16bit index S - 16bit stack [2] / index U - 16bit stack [3] / index PC - 16bit program counter [1] The 6809 uses this as the MSB for 8-bit direct addressing modes---it defaults to $00 on startup. [2] Hardware stack pointer, for use with BSR, JSR, and interrupts. Can also be used as an index register. [3] software stack pointer, meant to be used to pass parameters, but can also be used as an index register It also supports more addressing modes than the 6502 like position independant (indexed off PC) and indirect addressing (in C, this would be dereferencing a pointer). It also has a fairly orthogonal instruction set which also helps in compiler writing (in my opinion). Of all the 8bit CPUs, this happens to be my favorite. Probably a bit of both. I know the instruction set of the 8080/Z80 is not as orthogonal as the 6800/6809, with quite a few specialized instructions, and only a single accumulator. To use the 8086 as an example (since it's derived from the 8080), it takes quite a bit of compiler smarts to turn: int i; char *s = src; char *d = dest; for (i = 0 ; i < SIZE ; i++) *d++ = *s++; into: mov cx,SIZE mov si,[bp + src] mov di,[bp + dest] rep movsb ; a smart compiler might realize that s,d and i aren't ; used after this point, and discard the follow ; instructions ... (and this applies to each of the examples ; below as well) mov [bp + src],si mov [bp + dest],di mov word ptr [bp + i],SIZE A horribly written C compiler might produce (and I have seen this): mov ax,[bp + src] mov [bp + s],ax mov ax,[bp + dest] mov [bp + d],ax mov word ptr [bp+i],0 loop: mov ax,[bp + i] cmp ax,SIZE je loop_exit mov bx,[bp + s] mov al,[bx] inc bx mov [bp + s],bx mov bx,[bp + d] mov [bx],al inc bx mov [bp + d],bx mov ax,[bp + i] inc ax mov [bp + i],ax jmps loop loop_exit: while a slightly better one would see that s and d are used as memory pointers, and that i is used as a counter so it too could be used in a register: xor dx,dx mov si,[bp + src] mov di,[bp + dest] loop: mov al,[si] inc si mov [di],al inc di inc dx, cmp dx,SIZE jl loop mov [bp + s],si mov [bp + d],di mov [bp + i],dx You get the idea. You, looking at the C code, can guess immediately that you should probably use REP MOVSB, but a compiler can't guess that outright, at least, not without a lot of smarts. On the 6809 though, will look more like the above sequence (assuming a half-way decent compiler) and that's about as good as you can get, since the 6809 doesn't have specialized instructions: clra clrb std i,u ldx src,u ldy dest,u loop: lda ,x+ sty ,y+ ldd i,u addd #1 std i,u cmpd #SIZE bne loop stx src,u sty dest,u Although, if SIZE doesn't exceed 255, the compiler could produce: clrb ldx src,u ldy dest,u loop: lda ,x+ sta ,y+ incb cmpb #SIZE bne loop ldb #SIZE clr i_high,u stb i_low,u stx src,u sty dest,u Of course, you should replace: for (i = 0 ; i < SIZE ; i++) *d++ = *s++; with memcpy(dest,src,SIZE); which a C compiler is free to replace with: mov cx,SIZE mov si,[bp + src] mov di,[bp + dest] rep movsb or (on a 6809): ldb #SIZE ; assuming SIZE < 256 ldx src,u ldy dest,u loop: lda ,x+ sta ,y+ decb bne loop Even a poorly written compiler can be written with *that* amount of smarts (basically, inlining anything defined in <string.h>). But I'm digressing. -spc (Okay, should probably go to bed now ... )

Yes, and more... The 6809 is a pseudo-16-bit chip in many ways. OK, it's only got an 8 bit data path, but a lot of instructions operate on 16 bit data. IIRC, the registers are : A, B (2 accumulators, 8 bits each) which can be jointly called D (16 bit accumulator) U, S, 2 stack pointers (16 bits each, none of the 6502 problems of a stack in page 1 only) X, Y, 2 index registers, also 16 bits each P (Program counter, 16 bits) S (Status register, 8 bits) DP (Direct page register, 8 bits. This forms the 8 byte in 'direct page addressing mode', which is like zero page on a 6502, except it can refer to any page in memory). Also, the instruction set is orthogonal (very). There are few restrictions on what can be done to each register, and which addressing modes can be used with each instruction. IIRC, on the 6502 you can't transfer (driectly) between just any 2 registers, you can't push just any register onto the stack, etc. And there are relative addressing modes for jumps, calls and data access, allowing position-independant code. -tony

On Tue, Apr 27, 2004 at 10:19:50PM +0100, Tony Duell wrote: I have to agree with endorsing K&R... That's how I learned C twenty years ago. I don't think any of the books that have followed have done as good a job of presenting the material. Yes, C has changed, but that's window dressing compared to the underlying concepts. I still keep a copy handy when I'm starting a project (just as I always have the Camel book around for Perl). -ethan -- Ethan Dicks, A-130-S Current South Pole Weather at 28-Apr-2004 07:30 Z South Pole Station PSC 468 Box 400 Temp -74.0 F (-59.0 C) Windchill -117.4 F (-83 C) APO AP 96598 Wind 9.6 kts Grid 066 Barometer 677.4 mb (10723. ft) Ethan.Dicks(a)amanda.spole.gov http://penguincentral.com/penguincentral.html

----- Original Message ----- From: "Tony Duell" &lt;ard(a)p850ug1.demon.co.uk&gt; To: &lt;cctalk(a)classiccmp.org&gt; Sent: Wednesday, April 28, 2004 11:17 PM Subject: Re: Anybody ever use Aztec C for APPLEII? years good Couldn't agree more. Geoff.