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Newbie with Tiny68K [message #4150] Fri, 26 January 2018 08:57 Go to next message
smp is currently offline  smp
Messages: 49
Registered: January 2018
Location: Bedford, NH, USA
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Hello all,

I'm new here - I recently purchased a Tiny68K board from Bill Shen, and while I was waiting to be admitted here onto the Forum, I've been e-mailing with Bill. I'd like to make a few posts to recount my experiences for the benefit of others.

My board arrived safe & sound, and came up right away. I'm having difficulty with the USB-to-TTL converter trying to get CTS & RTS working. The cables I already had were all only 3-wire connections, with no CTS & RTS. Those all have worked fine for the terminal interface with CTS & RTS jumper together. Next, I tried one from eBay, but it only worked for the TX & RX, but not for CTS & RTS. I see that I screwed up and got a 3.3V version, so I am hopeful that my next try from Amazon will work. That one should arrive today. I'll give it a try and report back.

Thanks for listening!

smp
Re: Newbie with Tiny68K [message #4151 is a reply to message #4150] Fri, 26 January 2018 08:58 Go to previous messageGo to next message
smp is currently offline  smp
Messages: 49
Registered: January 2018
Location: Bedford, NH, USA
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Now that I've posted my first message, hopefully my links will now work...

I'm having difficulty with the USB-to-TTL converter trying to get CTS & RTS working. The cables I already had were all only 3-wire connections, with no CTS & RTS. Those all have worked fine for the terminal interface with CTS & RTS jumper together. Next, I tried this, from eBay:

https://www.ebay.com/itm/FTDI-FT232RL-USB-Cable-to-Serial-ad aptmodule-USB-TO-TTL-RS232-Arduino-Cable-PR/302571041695?ssP ageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

Again, this works for the TX & RX, but not for CTS & RTS. I see that I screwed up and got a 3.3V version, so I am hopeful that my next try will work:

https://www.amazon.com/gp/product/B010KII6VG/ref=oh_aui_deta ilpage_o00_s00?ie=UTF8&psc=1

This unit should arrive today. I'll give it a try and report back.

Thanks for listening!

smp
Re: Newbie with Tiny68K [message #4152 is a reply to message #4151] Fri, 26 January 2018 09:09 Go to previous messageGo to next message
smp is currently offline  smp
Messages: 49
Registered: January 2018
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Hi all,

I have the source code for a 68K Tiny Basic that is configured to work on an early Motorola trainer. The code is well documented and indicates the portion that would need to be modified for another system:
******************************************************
* The following routines are the only ones that need *
* to be changed for a different I/O environment.     *
******************************************************

*
* ===== Output character to the console (Port 1) from register D0
*	(Preserves all registers.)
*
OUTC	BTST	#1,$10040	is port 1 ready for a character?
	BEQ	OUTC		if not, wait for it
	MOVE.B	D0,$10042	out it goes.
	RTS

*
* ===== Input a character from the console into register D0 (or
*	return Zero status if there's no character available).
*
INC	BTST	#0,$10040	is character ready?
	BEQ	INCRET		if not, return Zero status
	MOVE.B	$10042,D0	else get the character
	AND.B	#$7F,D0		zero out the high bit
INCRET	RTS

*
* ===== Output character to the host (Port 2) from register D0
*	(Preserves all registers.)
*
AUXOUT	BTST	#1,$10041	is port 2 ready for a character?
	BEQ	AUXOUT		if not, wait for it
	MOVE.B	D0,$10043	out it goes.
	RTS

*
* ===== Input a character from the host into register D0 (or
*	return Zero status if there's no character available).
*
AUXIN	BTST	#0,$10041	is character ready?
	BEQ	AXIRET		if not, return Zero status
	MOVE.B	$10043,D0	else get the character
	AND.B	#$7F,D0		zero out the high bit
AXIRET	RTS

*
* =====	Return to the resident monitor, operating system, etc.
*
BYEBYE	MOVE.B	#228,D7		return to Tutor
	TRAP	#14

Since I am not yet a 68K programmer, I asked Bill what changes I need to make to the OUTC and INC routines to connect properly to the Tiny68K Monitor.

Bill replied with this:
Tiny68K uses the trap services of EASy68K.  So for console input it is task 5, console output is task 6 and console input pending is task 7.  You can also write directly to the 68681 registers, but the advantage of trap is you can simulate your code with EASy68K simulator.

The EASy68K compatible replacement routinte for OUTC & INC:
 
OUTC:
            movem.l d0-d1,-(sp)      * save reg d0,d1
            move.b d0,d1               * d1 contains the character to send
            move.b #6,d0                * console output trap service
            trap #15
            movem.l (sp)+,d0-d1     * restore register
            rts
 
INC:
            movem.l d1,-(sp)           * save reg d1
            move.b #0,d1                * assuming no input pending
            move.b #7,d0                * console ready?
            trap #15
            move.b d1,d0               * if zero, no input pending, exit
            beq done
            move.b #5,d0                * otherwise, get data into d1.b
            trap #15
            move.b d1,d0               * transfer to d0.b
done:
            move.l (sp)+,d1             * restore d1
            rts
 
There are no equivalent EASy68K trap services with the auxiliary port, so replace the host I/O with direct write to 68681 registers:
(I'm assuming the serial port B is already properly initialized...)
 
SRB     equ       $FFF013           * status reg of serial port B (read)
RHRB   equ       $FFF017           * Rx holding reg of serial port B (read)
THRB    equ       $FFF017           * Tx holding reg of serial port B (write)
 
AUXOUT:
            btst.b #2,SRB               * wait for transmit ready
            beq AUXOUT
            move.b d0,THRB           * put char out to serial port B
            rts
 
 
AUXIN:
            clr.b d0                         * assuming no char input ready
            btst.b #0,SRB               * does receiver has a char input?
            beq hostdone               * no input pending, exit with d0.b = zero
            move.b RHRB,d0          * get character into d0.b
hostdone:
            rts
 
As you can see the trap services are less efficient, but having the ability to simulate code is worth the overhead.
 
  Bill


With those I/O changes, I was able to get the Tiny Basic to start running, but quite a few more problems have arisen. Stay tuned!

smp
Re: Newbie with Tiny68K [message #4153 is a reply to message #4152] Fri, 26 January 2018 09:15 Go to previous messageGo to next message
smp is currently offline  smp
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Continuing my effort to get the Tiny Basic to run properly, I re-ORG'd the code to 4000H, and then it was apparently working. At this point, all characters that I type are echoed twice, but the BASIC is receiving the correct entries, and acting upon them. I tried BYE, NEW, and PRINT 1+2, and they all worked appropriately.

It appears that the code is sensitive to where it resides in memory, for some reason. From the beginning, I saw that the author expected the code to be in page 0, because he starts right out assuming the top of memory is only 16 bits:
*
* Modifiable system constants:
*
TXTBGN	DC.L	TXT		beginning of program memory
ENDMEM	DC.L	$FFFE   end of available memory
*
* The main interpreter starts here:
*
CSTART	MOVE.L	ENDMEM,SP	initialize stack pointer
	LEA	INITMSG,A6	tell who we are
	BSR.L	PRMESG
	MOVE.L	TXTBGN,TXTUNF	init. end-of-program pointer
	MOVE.L	ENDMEM,D0	get address of end of memory

That's why I've tried to stay in page 0. ORG at 4000H and top of memory at FFFEH seems to be working at this point, so, hopefully I don't have to crawl through all the code looking for the 16 bit restrictions and opening them up.

Thanks again for listening!

smp
Re: Newbie with Tiny68K [message #4154 is a reply to message #4150] Fri, 26 January 2018 09:26 Go to previous messageGo to next message
smp is currently offline  smp
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Hi again all,

I decided that the Tiny68K monitor TRAP must echo characters, so I found the one line in Tiny Basic to comment out within the GETLN routine. Double character echo fixed.

It gets a bit bizarre after that. It appears that everything in the Tiny Basic works in direct input mode. It also will let me enter a program, line by line, and LIST will print it all back to me. So far, so good. Then things start to get funny. After typing in one of my favorite test programs, and listing it out, the RUN command hangs. Rats!

I've spent a couple of hours skulking through the code, and nothing obvious (to me, anyway) stands out. I read the reprinted article from Dr. Dobbs, and that shed some light:

"One warning: the DIRECT and EXEC routines were written assuming that the interpreter itself would be somewhere in the first 64K of memory ($0 to $FFFF). If you move it above 64K, you will have to modify the EXEC routine and check the rest of the code carefully to make sure the addressing modes are correct."

So, the author admits to coding this to run only in page 0, and he doesn't know all the bits that will have to be changed to run in a higher page of memory.

I've played around quite a bit with getting the Basic loaded and then executing one or more direct commands, and typing in a program and try to run it. Most all of this playing around results with the RUN command hanging up. I can't recount all the different combinations that I tried, but I finally found this:

Reset the Tiny68K board.
Load the Tiny Basic s-record file.
Type in your program - don't do anything else but type in your program.
Type RUN.

This sequence will get your program to run successfully (if you typed everything in the program correctly).

The next LIST or RUN or PRINT command will hang!

I have Tera Term, so it's pretty easy to load the s-record file to get Tiny Basic running, and then modify the character and line delays to send in my program from a text file. That's how I've been able to try dozens of things and get to this point. I'm starting to doubt the robustness of the Tiny Basic code. Since I am a novice programmer on the 68K, I'd love to have you folks take a look. Maybe someone with more experience programming a 68000 will do better than I have on figuring this out.

Thanks for listening!

smp

[Updated on: Fri, 26 January 2018 09:39]

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Re: Newbie with Tiny68K [message #4156 is a reply to message #4154] Fri, 26 January 2018 09:34 Go to previous messageGo to next message
smp is currently offline  smp
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Here are the files for your inspection.

tbi68k12.ZIP is the original package I downloaded from the Internet.

TinyBasic68K.X68 is the original source code file with changes only to make it assemble without errors using EASy68K.

TinyBasic68Ksmp.X68 is the file with all my modifications in it, that is operating as described previously.

Folks, I'm interested in getting this Tiny Basic to work correctly on the Tiny68K board. I would greatly appreciate your inspection of what I've done here, and whatever observations, comments or ideas you may have will be very welcome!

smp
Re: Newbie with Tiny68K [message #4161 is a reply to message #4151] Fri, 26 January 2018 13:33 Go to previous messageGo to next message
smp is currently offline  smp
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smp wrote on Fri, 26 January 2018 11:58
I'm having difficulty with the USB-to-TTL converter trying to get CTS & RTS working...

https://www.amazon.com/gp/product/B010KII6VG/ref=oh_aui_deta ilpage_o00_s00?ie=UTF8&psc=1

This unit should arrive today. I'll give it a try and report back.



My cable arrived today, and it did not work for me at all. SIGH. It is now on it's way back to Amazon for a refund. This is starting to get frustrating. My TX & RX USB-to-TTL cables work fine. The 3.3V cable that I purchased by mistake works for TX & RX, but the CTS & RTS don't seem to be working. Now this $20 cable that had good reviews doesn't work for me at all.

I have a good working USB-to-RS232 interface - maybe I'll look for a RS232-to-TTL converter to attach to that.

Thanks for listening.

smp
Re: Newbie with Tiny68K [message #4164 is a reply to message #4161] Fri, 26 January 2018 16:06 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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Hi Stephen,
Welcome to the retrobrew forum.

I tried the TinyBasic68ksmp.X68 you uploaded and I believe have observed the same problem:

100 PRINT 1
RUN <-- run OK with correct answer
LIST <-- hang here

I do have a serial connection with working handshake, so the problem is not due to the handshake problem. I like to tackle the TinyBasic problem first. Perhaps other users may have answer to the serial port issue over the weekend. If not, I'll ship you a CP2102 adapter Monday. So let me see if I can figure out the TinyBasic...
Bill
Re: Newbie with Tiny68K [message #4165 is a reply to message #4164] Fri, 26 January 2018 17:29 Go to previous messageGo to next message
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Stephen,
The way the INC routine deals with character-not-ready is unusual. So instead of fighting it and making it works with EASy68K trap services, I just do the direct I/O method. You can see the I/O routines are similar to that of the auxiliary port.

I restored the echo routine you've commented out (BSR GOOUT).

Search for the string **X, those are my modifications to your TinyBasic68Ksmp.X68

I'm not familiar with TinyBasic, but here is my quick test after the modification:

----------------------------------
Gordo's MC68000 Tiny BASIC, v1.3
modified to operate on the Tiny68K board by Bill Shen


OK
> PRINT 23
23

OK
> 100 PRINT 1
> 200 PRINT 2
> 300 PRINT 1+2
> RUN
1
2
3

OK
> LIST
100 PRINT 1
200 PRINT 2
300 PRINT 1+2

OK
> RUN
1
2
3

OK
>
---------------------------------------

[Updated on: Fri, 26 January 2018 17:46]

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Re: Newbie with Tiny68K [message #4166 is a reply to message #4165] Sat, 27 January 2018 05:42 Go to previous messageGo to next message
smp is currently offline  smp
Messages: 49
Registered: January 2018
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Hi Bill,

Well, that certainly turned out to be kind of anticlimactic, didn't it?

Thank you for your attention on this. I'll be trying out that direct I/O code later on today, and I'll try and put the Tiny Basic through some more exhaustive testing.

It remains a mystery to me why the I/O code was the culprit causing the hang up like that...

smp
Re: Newbie with Tiny68K [message #4168 is a reply to message #4166] Sat, 27 January 2018 08:03 Go to previous messageGo to next message
mikemac is currently offline  mikemac
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smp wrote on Sat, 27 January 2018 06:42
Hi Bill,

Well, that certainly turned out to be kind of anticlimactic, didn't it?

Thank you for your attention on this. I'll be trying out that direct I/O code later on today, and I'll try and put the Tiny Basic through some more exhaustive testing.

It remains a mystery to me why the I/O code was the culprit causing the hang up like that...

smp


Basic interpreters often expect the keyboard routine to return even if there is no key pressed. They use that so you can interrupt the running of a program, otherwise you'd have to reset the whole board to break out of the program. I wouldn't be surprised if the routine you tried to use waits for a key to be pressed, thereby hanging the Basic interpreter.



Mike
Re: Newbie with Tiny68K [message #4173 is a reply to message #4168] Sat, 27 January 2018 10:12 Go to previous messageGo to next message
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mikemac wrote on Sat, 27 January 2018 11:03
Basic interpreters often expect the keyboard routine to return even if there is no key pressed. They use that so you can interrupt the running of a program, otherwise you'd have to reset the whole board to break out of the program. I wouldn't be surprised if the routine you tried to use waits for a key to be pressed, thereby hanging the Basic interpreter.


Hi Mike, thanks for your thought.

I agree with what you said, but the mystery for me is why would the TRAP service routines for I/O allow one direct command, like PRINT SIZE, and then hang on the second direct command? Or, why would the TRAP service routines allow me to enter a program line by line, and the RUN the program, and then hang on the next direct command? If it were as you said, then wouldn't the TRAP service routines cause a hang right away?

Oh, well, it doesn't really matter, I suppose. I'm just sorry that a new-to-me way of performing I/O didn't work out in this case.

smp
Re: Newbie with Tiny68K [message #4174 is a reply to message #4173] Sat, 27 January 2018 10:59 Go to previous messageGo to next message
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Hello again, all,

I've had the Tiny BASIC up and running for a few hours and it seems to be operating as advertised, once I put in Bill's changes to the I/O routines. So, for anyone who's interested, the code that Bill uploaded here is available for anyone who may want to run Tiny BASIC on their system.

One of my test programs that I use across my vintage machines is a routine to find all the ways to make $1.00 (US) from change (pennies, nickels, dimes & quarters). Here is the code I wrote for the 68K Tiny BASIC::
10 C=0
20 FOR P=0 TO 100 STEP 5
30 FOR N=0 TO 20
40 FOR D=0 TO 10
50 FOR Q=0 TO 4
60 IF P+(N*5)+(D*10)+(Q*25)<>100 GOTO 90
70 PRINT #3,"p=",P,"   n=",N,"   d=",D,"   q=",Q
80 C=C+1
90 NEXT Q
100 NEXT D
110 NEXT N
120 NEXT P
130 PRINT
140 PRINT C," ways to make $1.00 from change"
150 PRINT

With this program, I've "benchmarked" a variety of machines I have, for the fun of seeing how fast or slow they might be. Even the differences between BASICs on the same machine. I was a bit surprised about the difference between the Tiny BASIC and the CB68 compiling BASIC on CP/M 68K:

Tiny BASIC: 2 minutes 6 seconds
CB68: 4 minutes 6 seconds

My timing was by eye on a running digital clock, so the times are probably +/- a second or so, but, wow, I didn't expect 2 minutes difference between the two. The reason probably lies in CB68 performing floating point arithmetic, and Tiny BASIC performing integer arithmetic. I've taken measurements on several BASICs on several machines, and I have results running from 30 seconds to 26 minutes 21 seconds. So, the 8 MHz 68000 here is performing in the better-than-average category, as far as I'm concerned.

I hope that others will try out the Tiny BASIC for themselves. The original .ZIP file has a documentation file, as well as a few programs to tryout.

smp
Re: Newbie with Tiny68K [message #4175 is a reply to message #4174] Sat, 27 January 2018 12:42 Go to previous messageGo to next message
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Looks like TinyBasic is running well. Benchmarks are interesting. Here is another benchmark of various basic interpreter/compilers running on different machines based on one program:
https://www.retrobrewcomputers.org/forum/index.php?t=msg& ;th=201&goto=3306&#msg_3306

I'll try your program on the few machines I have.
Re: Newbie with Tiny68K [message #4177 is a reply to message #4175] Sat, 27 January 2018 15:33 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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Of course you can speed up performance by putting in a faster CPU with the corresponding oscillator. As a standard procedure to establish performance margin of every Tiny68K I built, I replace the 8MHz oscillator in every Tiny68K with 10 Mhz and 12 MHz oscillator and run memory diagnostics. All board will pass the 10MHz and 3 out of 4 will pass 12MHz. So your board will run at 10Mhz and most likely 12MHz. If you replace the CPU with 12Mhz part (MC68000P12 or MCHC68000P12), it is likely to run at 16MHz. The DRAM is fast enough to running at zero wait state at 12MHz but according to my paper calculation a wait state is needed at 16MHz, depending on the DRAM speed grade. I know I've ran Tiny68K at 16MHz with P12 part before. I tried it again just now with a MC68000P12 and 60nS DRAM SIMM, and it works just fine.

In term of availability, you may find DIP64 part at 12MHz, but DIP64@16MHz is hard to find. I'd be leery of the 16MHz part as well, it may be a slow part re-labelled so I'd only buy from reputable sellers. Faster 68000 are more likely packaged in the PLCC format. I have redesigned Tiny68K with PLCC package like the one in the picture and I generally run it at 16MHz (it is a 12MHz 68HC000 if you look closely).
Re: Newbie with Tiny68K [message #4179 is a reply to message #4177] Sat, 27 January 2018 19:35 Go to previous messageGo to next message
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smp,

I figured out why the trap services are not working. My mistake!
Just like Mikemac said that console input does not want to spinning forever waiting for input, so the INC routine checks for input, if no input returns to calling program with Zero flag set. My mistake is when restoring registers just before returning to the calling program, I used MOVE.L instruction which affects the condition flags. What I should use is MOVEM.L instruction which does not change the condition flags.

So attached is the TinyBasic using EASy68K trap services. My changes are marked with **X and they are:
1. turn off echo with task #12
2. restore the echo back routine you commented out (BSR GOOUT)
3. get rid of one unnecessary line in INC routine
4. change MOVE.L to MOVEM.L just before return
Re: Newbie with Tiny68K [message #4180 is a reply to message #4179] Sun, 28 January 2018 05:43 Go to previous messageGo to next message
smp is currently offline  smp
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Hi Bill,

Thanks very much for the speed upgrade info, and also for your effort to get the original TRAP service I/O to work.

smp
Re: Newbie with Tiny68K [message #4181 is a reply to message #4150] Sun, 28 January 2018 05:47 Go to previous messageGo to next message
smp is currently offline  smp
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For the benefit of anyone who is interested, here is a complete set of files for the Tiny BASIC with the direct I/O routines.

TinyBasic68Ksmp.X68 - assembler source text file
TinyBasic68Ksmp.S68 - s-record file ready to load
TinyBasic68Ksmp.L68 - assembly listing text file

All these files were generated from the EASy68K assembler application.

Enjoy!

smp

[Updated on: Sun, 28 January 2018 05:51]

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Re: Newbie with Tiny68K [message #4195 is a reply to message #4177] Mon, 29 January 2018 11:56 Go to previous messageGo to next message
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plasmo wrote on Sat, 27 January 2018 18:33
Of course you can speed up performance by putting in a faster CPU with the corresponding oscillator. <...snip...>


I must be doing something wrong. I always try to find parts at several places like Jameco, DigiKey and Mouser. Sometimes I have to experiment to determine how they describe the part that I'm looking for. I determined that I'm looking for a 12 MHz half-can oscillator. I've also tried half-can crystal oscillator, and half-DIP oscillator. I can find some half-can oscillators, but none at 12 MHz or 16 MHz.

Can anyone give me a pointer to a place that I can purchase the required 12 MHz and 16 MHz half-can oscillators to experiment with my board?

Thanks in advance, for any pointers or links that you may be able to provide.

smp

[Updated on: Mon, 29 January 2018 11:57]

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Re: Newbie with Tiny68K [message #4196 is a reply to message #4150] Mon, 29 January 2018 12:03 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Try these P/Ns (both as 5V parts, standard pinout):
ECS-2100AX-120
ECS-2100AX-160

Digi-Key has them both.
Re: Newbie with Tiny68K [message #4198 is a reply to message #4196] Mon, 29 January 2018 12:13 Go to previous messageGo to next message
smp is currently offline  smp
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Andrew B wrote on Mon, 29 January 2018 15:03
Try these P/Ns (both as 5V parts, standard pinout):
ECS-2100AX-120
ECS-2100AX-160

Digi-Key has them both.


Thanks a million, Andrew! I now have one of each on order.

smp
Re: Newbie with Tiny68K [message #4210 is a reply to message #4198] Tue, 30 January 2018 08:47 Go to previous messageGo to next message
smp is currently offline  smp
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smp wrote on Mon, 29 January 2018 15:13
Andrew B wrote on Mon, 29 January 2018 15:03
Try these P/Ns (both as 5V parts, standard pinout):
ECS-2100AX-120
ECS-2100AX-160

Digi-Key has them both.


Thanks a million, Andrew! I now have one of each on order.

smp


Along with those two oscillators, I've also purchased this:

https://www.ebay.com/itm/1x-MOTOROLA-MC68000P12F-16MHZ-DIP-6 4-16-32-BIT-16Mbyte-ADDRESS-RANGE/112636890643?ssPageName=ST RK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

This eBay Seller has good feedback, so I thought it might be worth the risk. I'll report back on how it works (or not).

smp
Re: Newbie with Tiny68K [message #4211 is a reply to message #4161] Tue, 30 January 2018 08:53 Go to previous messageGo to next message
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smp wrote on Fri, 26 January 2018 16:33
smp wrote on Fri, 26 January 2018 11:58
I'm having difficulty with the USB-to-TTL converter trying to get CTS & RTS working...

https://www.amazon.com/gp/product/B010KII6VG/ref=oh_aui_deta ilpage_o00_s00?ie=UTF8&psc=1

This unit should arrive today. I'll give it a try and report back.



My cable arrived today, and it did not work for me at all. SIGH. It is now on it's way back to Amazon for a refund. This is starting to get frustrating. My TX & RX USB-to-TTL cables work fine. The 3.3V cable that I purchased by mistake works for TX & RX, but the CTS & RTS don't seem to be working. Now this $20 cable that had good reviews doesn't work for me at all.

I have a good working USB-to-RS232 interface - maybe I'll look for a RS232-to-TTL converter to attach to that.

Thanks for listening.

smp


Just for the record, I am still dead in the water when it comes to hitching up a working SIO connection to my terminal that also has CTS & RTS. I can only use the cables I already have for TX & RX only with CTS & RTS jumper together on the Tiny68K board.

I'm not the brightest when it comes to serial connections. I also have a good USB-to-RS232 cable. Can anyone provide me a step-by-step procedure to acquire a RS232-to-TTL adapter and get it wired up properly to provide the needed CTS & RTS? I would greatly appreciate some detailed advice with pictures if possible.

Thanks in advance!

smp
Re: Newbie with Tiny68K [message #4215 is a reply to message #4211] Tue, 30 January 2018 09:49 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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smp,

I corresponded via email with another user who also experienced RTS/CTS handshake problem. He was using the FTDI brand of USB adapter. He received a CP2102 USB adapter over the past weekend and the handshake problem is now resolved. I think the FTDI brand of USB adapters have problems for some (myself included).

I have a spare CP2102 adapter that I wired up with an adapter board so they plug straight into the 6-pin Tiny68K serial port without additional wiring. I can mail it to you if you like. You'll need a USB 2.0 extension cable (not USB A-to-B which has a square end) to connect this.

Your board should run at 12 MHz without changing the 68000. When changing the 68000 you need a tool with a bend like this: https://www.ebay.com/itm/New-2-Pairs-Cross-Lock-Tweezers-Sel f-Closing-Fiber-Grip-4-Bent-Straight-tip/321808761311, slide the tool under the IC and gently pry up the 68000. Move forward a little bit and pry up again and repeat until the chip comes clean off. When inserting a new 68000, the row spacing of a new part is too wide for the socket, so you need to bend each row against a hard surface to get the proper row spacing. Align them carefully with the sockets before press it down. Aligning 2 long rows of pins can be tricky. Take your time.
Re: Newbie with Tiny68K [message #4221 is a reply to message #4215] Tue, 30 January 2018 15:08 Go to previous messageGo to next message
smp is currently offline  smp
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Hi Bill,

I found these CP2102 adapters. Is any of these what I need?

https://www.amazon.com/KEDSUM-CP2102-Module-Download-Convert er/dp/B009T2ZR6W
https://www.amazon.com/WINGONEER-CP2102-Module-Serial-Conver ter/dp/B01LRVQIFQ/ref=pd_sbs_147_1?_encoding=UTF8&pd_rd_ i=B01LRVQIFQ&pd_rd_r=ZTQV432JGPYBX20PWDFB&pd_rd_w=a8 wBp&pd_rd_wg=uoJGW&psc=1&refRID=ZTQV432JGPYBX20P WDFB
https://www.amazon.com/CP2102-UART-6PIN-Serial-Converter/dp/ B00CD264HG

Can you please tell me how you get the RTS signal instead of the DTR signal off the board? Actually, I think the WINGONEER one has the RTS hole labeled. Perhaps that's the one I ought to get? I can solder a post into the RTS hole and then use the jumper cables to attach to the Tiny68K board, and the USB extension cable to attach to my computer. Right?

Thanks very much for any advice you can offer.

smp

[Updated on: Tue, 30 January 2018 15:23]

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Re: Newbie with Tiny68K [message #4222 is a reply to message #4215] Tue, 30 January 2018 15:36 Go to previous messageGo to next message
smp is currently offline  smp
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plasmo wrote on Tue, 30 January 2018 12:49
Your board should run at 12 MHz without changing the 68000. When changing the 68000 you need a tool with a bend like this: https://www.ebay.com/itm/New-2-Pairs-Cross-Lock-Tweezers-Sel f-Closing-Fiber-Grip-4-Bent-Straight-tip/321808761311, slide the tool under the IC and gently pry up the 68000. Move forward a little bit and pry up again and repeat until the chip comes clean off. When inserting a new 68000, the row spacing of a new part is too wide for the socket, so you need to bend each row against a hard surface to get the proper row spacing. Align them carefully with the sockets before press it down. Aligning 2 long rows of pins can be tricky. Take your time.


Hi again, Bill, and thanks very much for your advice on the speedup process.

I plan to first try the 12 MHz oscillator. I had hoped that the P8 processor would maybe work. Thanks for verifying that it will.

I had trouble with the link you provided, but I found this:

https://www.amazon.com/TWEEZERS-POINTED-CLOSING-SOLDERING-NO VELTOOLS/dp/B010EAQQFS

Is this what I need?

Thanks a million for all your attention and advice!

smp
Re: Newbie with Tiny68K [message #4223 is a reply to message #4222] Tue, 30 January 2018 17:34 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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This is the picture of the tweezers I used to remove 68000. You need a way of getting under the device and lift up gently and repeat the process. A small spoon may work as well.
index.php?t=getfile&id=811&private=0

This is the CP2102 board and how I wired in the RTS and CTS. The RTS, CTS are not present on the 6-pin header so I need to build a small adapter board and bring the signals out from the pc board. I think this one from amazon is like mine. https://www.amazon.com/Honbay-CP2102-Module-Download-Convert er/dp/B01A0BOGHG/ref=sr_1_9?s=electronics&ie=UTF8&qi d=1517362187&sr=1-9&keywords=cp2102+usb
Re: Newbie with Tiny68K [message #4225 is a reply to message #4223] Tue, 30 January 2018 17:49 Go to previous messageGo to next message
smp is currently offline  smp
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plasmo wrote on Tue, 30 January 2018 20:34
This is the picture of the tweezers I used to remove 68000. You need a way of getting under the device and lift up gently and repeat the process. A small spoon may work as well. <...snip...>

This is the CP2102 board and how I wired in the RTS and CTS. The RTS, CTS are not present on the 6-pin header so I need to build a small adapter board and bring the signals out from the pc board. I think this one from amazon is like mine. <...snip...>


Thanks very much, Bill. I think I have the picture now. One of your pictures shows that there is a silk screen on the underneath of the board - that explains how the description of some of these boards indicates that all the signals are clearly marked, even though in the picture shown they certainly are not.

I'm going to go ahead and order the CP2102 from Amazon. As far as the tool to lift the 68000 out of the socket goes, I understand what you are saying, and I'll see what implement I have that can do the job. I get it - slow and careful will get the job done.

Thanks again!

smp

[Updated on: Tue, 30 January 2018 17:51]

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Re: Newbie with Tiny68K [message #4227 is a reply to message #4225] Wed, 31 January 2018 00:44 Go to previous messageGo to next message
googlefish is currently offline  googlefish
Messages: 3
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I'm the other guy who had problems with CTS/RTS signals and the FTDI adapter.

Now I have two working adapters from amazon:
WINGONEER USB 2.0 to TTL UART 6PIN CP2102 Module Serial Converter
Diymore 2Pcs CP2102 USB 2.0 to TTL UART Module 6-Pin Serial Converter STC Replace FT232 Module

both are working.
They have slight different pin layout, but it's documented on the board.
I use 1:1 connection with these 5 pins, nothing more:
GND
Txd
RxD
CTS
RTS

thanks
Stephan

P.S. sorry no real links, I'm not yet allowed to send them.

[Updated on: Wed, 31 January 2018 00:49]

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Re: Newbie with Tiny68K [message #4230 is a reply to message #4227] Wed, 31 January 2018 17:54 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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Thanks for the list of CP2102 that worked for you. This is the link to Diymore CP2102:
https://www.amazon.com/Diymore-CP2102-Module-Converter-Repla ce/dp/B0755DBGJM/ref=sr_1_1?ie=UTF8&qid=1517449844&s r=8-1&keywords=Diymore+2Pcs+CP2102+USB+2.0+to+TTL+UART+M odule+6-Pin+Serial+Converter+STC+Replace+FT232+Module

2 pcs for $6.88 and free shipping. They look just like my CP2102.
Re: Newbie with Tiny68K [message #4232 is a reply to message #4230] Wed, 31 January 2018 18:21 Go to previous messageGo to next message
adx is currently offline  adx
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I was successful with an FTDI based adapter that I have from Sparkfun. It's this model https://www.sparkfun.com/products/9716. I also have a known genuine ftdi based cable at work that I'll try once I find it. I wonder if the people who are having difficulties with them have ran into the counterfeit chips.

[Updated on: Wed, 31 January 2018 18:22]

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Re: Newbie with Tiny68K [message #4233 is a reply to message #4232] Wed, 31 January 2018 21:20 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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adx,
What is your computer's operating system? I'm running Windows Vista and I know the latest FTDI driver does not support Windows Vista, so I'm using an older driver.
Including myself there are 4 users with FTDI RTS/CTS handshake problems. Two bought the adapters from China, the other two are from Amazon. The problem MAY due to counterfeit parts, but the distribution channels are pretty far apart. I guess I should contact FTDI tech supports to see if they know about this issue.
Re: Newbie with Tiny68K [message #4235 is a reply to message #4233] Thu, 01 February 2018 03:59 Go to previous messageGo to next message
adx is currently offline  adx
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I'm using OS X. It could be a driver issue on Vista.
Re: Newbie with Tiny68K [message #4236 is a reply to message #4235] Thu, 01 February 2018 05:55 Go to previous messageGo to next message
googlefish is currently offline  googlefish
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hm, I'm using OS X too.
Have you tried GKermit?
That was my problem with the FTDI cable.
Re: Newbie with Tiny68K [message #4237 is a reply to message #4236] Thu, 01 February 2018 08:29 Go to previous messageGo to next message
smp is currently offline  smp
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I have two different CP2102 units on order:

https://www.ebay.com/itm/Black-5V-CP2102-USB-to-TTL-Serial-A dapter-Module-for-Lilypad-Arduino-Pro-Mini/362018308267?ssPa geName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649
https://www.amazon.com/gp/product/B01LRVQIFQ/ref=od_aui_deta ilpages00?ie=UTF8&psc=1

The second one is the WINGONEER that matches with Stephan, I think. Since I also am using Mac OSX, I am hopeful this will do the trick for me. The ability to use GKermit with the Tiny68K board is pretty critical.

Along with those, I have a number of bits & bobs coming along. I'll continue to post about my experiences, as soon as I have them. Cool

smp

[Updated on: Thu, 01 February 2018 08:31]

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Re: Newbie with Tiny68K [message #4238 is a reply to message #4236] Thu, 01 February 2018 09:01 Go to previous messageGo to next message
adx is currently offline  adx
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Quote:

hm, I'm using OS X too.
Have you tried GKermit?
That was my problem with the FTDI cable.


I don't think I'd waste my time trying gkermit. You're just as likely to hit tty layer incompatabilities has hardware issues. I use minicom installed via Homebrew. Another option would be to try out picocom. It's super light weight.
Re: Newbie with Tiny68K [message #4239 is a reply to message #4237] Thu, 01 February 2018 09:02 Go to previous messageGo to next message
googlefish is currently offline  googlefish
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I have both and both are working.
Little different pinlayout but clearly printed on the board.

I'm sure it works for you, too.
Re: Newbie with Tiny68K [message #4240 is a reply to message #4238] Thu, 01 February 2018 10:24 Go to previous messageGo to next message
smp is currently offline  smp
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adx wrote on Thu, 01 February 2018 12:01
I don't think I'd waste my time trying gkermit. You're just as likely to hit tty layer incompatabilities has hardware issues. I use minicom installed via Homebrew. Another option would be to try out picocom. It's super light weight.


Hi, and thanks very much for your thoughts.

To this point, the only way I see to get anything other than a plain text file into CP/M-68K is via GKermit. Can you elaborate a little on your suggestion of Minicom and Picocom? I Googled a little bit, but I have not yet been able to find out any information. Are these CP/M-68K applications that you can somehow get into the filesystem on the Tiny68K board? I would definitely like to know more about these.

Thanks!

smp
Re: Newbie with Tiny68K [message #4241 is a reply to message #4240] Thu, 01 February 2018 10:48 Go to previous messageGo to next message
plasmo is currently offline  plasmo
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The main reason Tiny68K needs RTS/CTS handshakes is to work with gkermit. The software is already installed so all you need is type "gkermit -r" to receive files from PC or "gkermit -t filename" to send filename to PC. I'll be interested in alternative file transfer methods as well because if we don't need gkermit, then I can remove the RTS/CTS requirements which has caused more problems than all other issues combined.
Re: Newbie with Tiny68K [message #4242 is a reply to message #4240] Thu, 01 February 2018 11:59 Go to previous messageGo to previous message
smp is currently offline  smp
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smp wrote on Thu, 01 February 2018 13:24
<...snip...>To this point, the only way I see to get anything other than a plain text file into CP/M-68K is via GKermit. Can you elaborate a little on your suggestion of Minicom and Picocom? I Googled a little bit, but I have not yet been able to find out any information. Are these CP/M-68K applications that you can somehow get into the filesystem on the Tiny68K board? I would definitely like to know more about these.<...snip...>


More Googling got me the information that both Minicom and Picocom are minimalist terminal emulation programs that run on Linux. They seem to be good substitutes for Hyper Terminal or Tera Term. They do not substitute for the CP/M application that can send and receive files from inside the CP/M-68K filesystem.

smp
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