Working SBC-3

[RichLeary]

It does indeed - thanks. I must have an out of date parts list & I will certainly just use NTSC.

Thanks,

Rich

[8BIT]

Rich has pointed out an error in my Parts list in the SBC-3 support file that can be downloaded from my website. I have updated that file with the correct info.

Thanks Rich!!!

Daryl

[DaveK]

I've finished my SBC-3 finally. It powers up and I can type commands into the monitor, but I can't XMODEM in either direction! It just gives ''Transfer error!" and a register dump. I'm using the default settings of 9600/8n1 but have also tried taking it down to 2400/8n1. I think the parameters are correct though, as a message to start sending and a bunch of C's come up on the terminal.

Edit: Bah. I've already read this somewhere when I took account of it in my own 6502 SBC. It's Tera Term repeating the first packet.

[8BIT]

Thanks for the message. I have not tried Teraterm. Time permitting, I'll give it a try tonight.

Daryl

[8BIT]

I just downloaded teraterm at work. Are you using CRC mode? The default is checksum, which my program does not support.

I'll give it a test though, to be sure the CRC mod is working.

Daryl

[RichLeary]

Daryl & the Group,

I finally got up my courage to start assembly following the guidelines, especially the SMT advice. I must admit that this was my first real attempt at SMT soldering.

The guidelines are great. I used a ton of flux, a very small chisel point on my iron, and small diameter solder (it did have a core). The other item I found essential was Solder-Wick (the real stuff not the Radio Shack version). With a strong light and magnifying helmet it was just a matter of a little patience.

IC2 was tough but after I thought I was done I cleaned the fux off the board and did a close insopection. I think everything is good but the proof of the poudding will come later when I power it up after adding everything else.

After IC2, IC5 was easy.

I have mounted C18 & C19 on the bottom and trimmed the leads as tight as possible. The IC4 socket fits OK with that approach without having to drill any holes in it.

I have a lot more to add and then the testing will be critical but I am happy with my progress and especially the IC2 & IC5 results.

Rich

[8BIT]

Excellent Rich! The rest should go easy. Let me know if you have questions or run into problems.

Daryl

[8BIT]

DaveK wrote:

I've finished my SBC-3 finally. It powers up and I can type commands into the monitor, but I can't XMODEM in either direction! It just gives ''Transfer error!" and a register dump. I'm using the default settings of 9600/8n1 but have also tried taking it down to 2400/8n1. I think the parameters are correct though, as a message to start sending and a bunch of C's come up on the terminal.

Edit: Bah. I've already read this somewhere when I took account of it in my own 6502 SBC. It's Tera Term repeating the first packet.

Just finished the upload test. I have TeraTerm Pro Web 3.1.3.

On the SBC, press "U" <enter>

The teraterm window should show a prompt and a series of "C"'s.

Click File -> Transfer -> XMODEM ->SEND
Select the file to send from the PC to the SBC. It should have the starting address as the first two bytes. Be sure not to overwrite the Monitor code in upper block 0.

Under the file selection are three bubbles: Checksum, CRC, and 1K. The bubble should be on CRC. Now click OPEN and the file should be transferred.

To copy a file to a block other than 0, type the <block #>U<Enter>,
For example, 02U<Enter> will load a file into block 2.

For instance, upload the yosemite.bin (found to the tools folder of the support file) to block 2. Then type 00030:2<enter> to see the image. type (blindly) 00030:1<enter> to return to the text page.

Hope this helps!

If not, you can email me for more help.

I wrote:

The xmodemsend command is not mapped into the monitor's command set. I did a quick test and was able to send a file, however, it did not work as designed and I'll need to further test it.

Oops. It is mapped: command "P". My memory is starting to fail. I'll test it tonight.

Add that to the list of things to re-check.

Daryl

[8BIT]

Dave,

Both U and P worked for me using hyperterminal and teraterm 3.1.3.

If you are still having trouble, send me an email with more details and we'll figure it out.

Daryl

[RichLeary]

I finished my SBC-3.1 and it is working. I still need to test the XMODEM transfers but I suspect that will not be a problem.

So far only used a monochrome monitor. Will try a color one soon.

I had one momentary concern when I could not get the > prompt. Turns out I had not installed the two jumpers between the VIA chips. Once I did that following the picture of Daryl's board all was well.

Rich

[8BIT]

Richard,

Glad to hear its working! Try downloading one of the picture files to test your color output.

I should have the EhBASIC files ready tomorrow, if you are interested in them. You can use xmodem to LOAD and SAVE programs.

Daryl

[8BIT]

RichLeary wrote:

... I had one momentary concern when I could not get the > prompt. Turns out I had not installed the two jumpers between the VIA chips. Once I did that following the picture of Daryl's board all was well.

Rich,

Thanks for pointing that out. I did overlook the instructions for placing the jumpers. I'll get those update tomorrow as well.

thanks

Daryl

[RichLeary]

Daryl,

I have noticed something strange with keyboards. I have four PS2 keyboards including two brand new Microsoft 500 keyboards. The Microsoft keyboards do not work withy the SBC3. The NUM LOCK light does not come on and there is no response to any key.

I also tested a Kensington keyboard but since that one used a USB to PS2 adapter I was not too surprised when it did not work.

The one that I have that works is an older Dell keyboard. I also have a newer HP keyboard but have not tested it yet.

Any thoughts?

Rich

[RichLeary]

All,

One tip I meant to post when I first finished by SBC3 was one regarding the heatsink. I mounted mine so the fins were on the outside of the board. That eliminated any conflict with the caps and might actually improve cooling air flow.

That does restrict mounting but since the power plug sticks out on the same side it did not seem like a big restriction.

Rich

[8BIT]

RichLeary wrote:

Daryl,

I have noticed something strange with keyboards. I have four PS2 keyboards including two brand new Microsoft 500 keyboards. The Microsoft keyboards do not work withy the SBC3. The NUM LOCK light does not come on and there is no response to any key.

I also tested a Kensington keyboard but since that one used a USB to PS2 adapter I was not too surprised when it did not work.

The one that I have that works is an older Dell keyboard. I also have a newer HP keyboard but have not tested it yet.

Any thoughts?

Rich

No, The three keyboards I have are cheap generic models and they all work. I have not really studied the keyboard specs or options. The code I created was modified from someone else's code (might have been Lee's) and it seemed to work without issue.

Here are some possible thoughts:

It could be timing related. However, as I remember, the keyboard clocks at the 10-30 khz rate so that should not really be an issue for a 8MHz microcontroller.

Its also possible that the keyboards are defaulting to something other than scan-code set 2, which I believe is the usual default.

Here is a link to a helpful website.
http://www.beyondlogic.org/keyboard/key ... ?the_id=16

Now, in order to figure this out, you would have to use another medium to communicate with the keyboard to determ what is being sent. I wrote a simple program to interface a pc keyboard through a 6522. You could use that on your SBC-2 along with the simple circuit (see the IO section of my website) to try to figure it out.

Alternatively, if you want to send me one, I can do the same and try to figure out the problem.

Daryl