2 sio

[marty]

Hi Geoff;
Do you have another 2-sio and could you send to me what flavors (vanilla , cherry, whoopse L, LS , or plain) is each of the Ic's you have in a working board, I am wondering if I have a slow Ic, so that the board works in echo mode , but not when running character after character, such as downloading.
THANK YOU Marty

[Geoff Harrison]

Hi Geoff;
could you send to me what flavors (vanilla , cherry, whoopse L, LS , or plain) is each of the Ic's you have in a working board


Hi Marty

I have posted an image of my 2sio board here (http://www.solivant.com/misc_images/2sio.jpg), it should be big enough to make out the chip markings. It's populated only for RS232, I didn't install any of the current loop stuff.

How close are you to getting yours working? I've used mine many times for loading BASIC, but only up to 4800 baud. If I remember correctly, I ran it for a while at 9600 but I had to insert inter-character delays in TeraTerm to get the uploads to work reliably.

Geoff.

[Geoff Harrison]

Oh, also, don't forget to make sure you do the uploads in binary mode.
It seems like I make that mistake almost Every D**mn Time!!!:rolleyes:

[marty]

Hi Geoff;
THANK YOU THANK YOU for your prompt reply !!!!!!!!
Your Board Looks soooo neat and nice ... Great Work !!!!!! :cool: :D :cool: :D
THANK YOU Marty

[marty]

Hi Geoff;
I noticed that above ic's K and M You do not have pin 4 wired along with 1 and 2 which I don't have wired on port 0 , but have wired on port 1...
And yes, I download at 4800, won't work at any faster rate, but I have had to use my single port s i/o , it is my ACR without the cassette section, as that never worked, and I have added on a small board a 1488 and 1489 for RS232.
So I use it for my downloads... but it would be nice to get my 2 si/o working.
THANK YOU Marty

[marty]

Hi Geoff;
Well, I took out all the wires for pins 1 and 2 and 4 for 'D' and 'E' and all the wires to the connector associated with these pins. and I took out all of the resistors and caps and diodes below the molex connectors.. hoping that, that would make a difference... but it didn't.. The board still passes the echo test, but will not download correctly.... it is at 4800 baud... I can slow it down to 300 baud, and just try the second stage loader. to see if that helps....
Any Ideas ?????? :( :) :confused: You are becomming the Sio Man !!!! :rolleyes:
THANK YOU Marty

[Geoff Harrison]

I noticed that above ic's K and M You do not have pin 4 wired along with 1 and 2


Yes, I brought out only the Tx & Rx lines and left RTS, CTS, & DCD disconnected. To keep the 6850 happy I tied pins 23 & 24 to ground.

http://www.solivant.com/misc_images/2sio_jumpers.jpg


The board still passes the echo test, but will not download correctly.... it is at 4800 baud... I can slow it down to 300 baud, and just try the second stage loader. to see if that helps.
Any Ideas ??????


I think it's worth taking it down as slow as you can drive it (300, even 110) to see if you get anywhere.

When you run the echo test and hold down a key to send a stream of characters, does it echo correctly or does it garble or miss characters?

If you're using TerraTerm to send the paper tape image, try setting an inter-character delay. I don't remember if HyperTerm lets you do that too.

When the Altair is running the loader waiting for you to send the tape, the address and status lights should show a steady, unchanging pattern. Then when you start sending the tape, the lights should change to a different pattern and flicker slightly, though it may be pretty subtle. If the lights never change from their original pattern, my guess would be that the 2SIO is not receiving a full 8 bit data stream. If the lights do change then the loader found the start token, if it has trouble after that it will generally print some sort of error code.

What loader are you using and what are you trying to load?


You are becomming the Sio Man


That might be a case of the blind leading the blind.

Geoff.

[marty]

Hi Geoff;
I will make the modifications to the board , as shown in your picture.. Thank You... I am using the standard 2-sio loader and 4 or 8K basic with a .tap ending. (along with the cassette copies) and I have put all of them on paper tape, as a backup.... I have all of these files in a file on my computer, and yes I am using teraterm.... I will let you know what I find... THANK YOU Marty

[marty]

Hi Geoff;
I got it to load at 4800 , but it has trouble with the letters on the screen, I changed it to 7 bits, but that made it worse, so I changed it back to 8 bits, then most of the letters seem to go thru... I reloaded it at 2400 baud , and it still does the same thing.... I will try it at 300 baud and see what happens..
THANK YOU Marty

[marty]

Hi Geoff;
It does the same thing at 300 baud...
here is was is shown on the screen: :confused: :confused:

( bit set to 7)
>"TIU*)*(S W%E black square )H!UP'TJ black square [ with line in middle

( changed to 8 bits)

WANT SI two parrellel bars ? black square
( used capital answers)
WANt SI two parrellel bars ? N
WANT RN-? N
WANT SQ pii ? N
58317 BYTES FRE a large + sign
[4K VERSION black rectangle

0 pii with line on top of it

(if it is in lower case letter i have attempted to describe what is there.)

( or told what I did)

THANK YOU Marty

[Geoff Harrison]

Hi Geoff;
It does the same thing at 300 baud...
here is was is shown on the screen: :confused: :confused:


If you're getting this far, I don't think you have a communication problem. What you show above is exactly what I get with 4k BASIC with 8N1 parameters. When you set it to 7 bits, do you also set parity to E? If you leave it set to None, you'll get garbage like you described.

Geoff.

[marty]

Hi Geoff;
THANK YOU, THANK YOU !! :D :D
I didn't remember reading that on the paper about boot loaders and Basic, I must have missed that part ... :o :o
Also, I think that putting in the wires from pins 23 and 24 to ground was/ is a BIG part of solving the problem, before that it would only work in echo mode.
THANK YOU Marty

[marty]

hi Geoff;
That took care of the problem ... :cool: :cool: :cool:
THANK YOU Marty :D :D :D