[Techtoolslist] RASTER: FW: Using 8080 pod on Midway 8080 boards (Space Invaders)

[John Robertson]

David Shoemaker wrote:

> I missed the resistor trick, will have to try that tomorrow.

>

> Have you backed up the midway test card rom?  I saw a picture of that board

> and it looks pretty darn simple to reproduce but I didn't have a copy of the

> rom image.

>

> David

>   


That didn't work (zip attachment).

So...I've added all my Midway test files to the ftp site:

TTL/Test_Equipment/Midway

John :-#)#


> -----Original Message-----

> From: techtoolslist-bounces at flippers.com

> [mailto:techtoolslist-bounces at flippers.com] On Behalf Of John Robertson

> Sent: Thursday, February 21, 2013 10:10 PM

> To: techtoolslist at flippers.com

> Subject: Re: [Techtoolslist] RASTER: FW: Using 8080 pod on Midway 8080

> boards (Space Invaders)

>

> David Shoemaker wrote:

>   

>> Hmm, ok well that doesn't bode well for my pods.

>>

>> I can't get anything close to a reliable memory test and no Run UUT

>>     

> success.

>   

>> I often get pod power failure.  This is on a known good working board set.

>>

>> Both my pods have the short flat cables.  I see another 8080 up on 

>> ebay with a longer twisted pair style cable but they are asking $200 

>> for it.  No way I am doing that at this point.

>>   

>>     

> Ah, well that is different. I too have had trouble with the pods on the

> Midway 8080 systems. Have you tried the resistor trick that Andrew pointed

> out? I'm going to be testing a reluctant board set soon and am looking

> forward to getting reliable RAM etc tests. I do have the Midway RAM Test

> card and that is a big help, but it would be best if the pod worked

> properly.

>

> Short flat ribbons work fine on my Z80 pod running a Galaga so I see no

> reason they wouldn't work on an 8080 pod. The advantage to the twisted pair

> cable is it can be longer making it easier to move the pod out of the way.

>

> John :-#)#

>   

>> -----Original Message-----

>> From: techtoolslist-bounces at flippers.com

>> [mailto:techtoolslist-bounces at flippers.com] On Behalf Of John 

>> Robertson

>> Sent: Thursday, February 21, 2013 9:15 PM

>> To: techtoolslist at flippers.com

>> Subject: Re: [Techtoolslist] RASTER: FW: Using 8080 pod on Midway 8080 

>> boards (Space Invaders)

>>

>> David Shoemaker wrote:

>>   

>>     

>>> What I am trying to figure out is are both my pods bad (which I doubt 

>>> as two are behaving the same way) or is my 9010.

>>>   

>>>     

>>>       

>> If you are wondering if the base (9010/9100) affects the Run UUT 

>> command the answer is no. When the pod is in the RUN UUT mode it is 

>> entirely independent from the base - other than it can be over-ridden 

>> with a command - it does not talk to the base at all. This is covered

>>     

> somewhere in the manuals...

>   

>> Some of the manuals are searchable - look up RUN UUT and see what is 

>> written, pretty sure I've remembered it correctly. All the base does 

>> is tell the CPU where the Reset Vector is, after that the pod is on it's

>>     

> own.

>   

>> John :-#)#

>>   

>>     

>>> -----Original Message-----

>>> From: prvs=1763d5e072=ayeckley at sierralobo.com

>>> [mailto:prvs=1763d5e072=ayeckley at sierralobo.com] On Behalf Of Alex 

>>> Yeckley

>>> Sent: Wednesday, February 20, 2013 4:15 AM

>>> To: 'David Shoemaker'; 'Technical Tools Mail List'; jrr at flippers.com; 

>>> rasterlist at vectorlist.org

>>> Subject: RE: [Techtoolslist] RASTER: FW: Using 8080 pod on Midway 

>>> 8080 boards (Space Invaders)

>>>

>>>   

>>>     

>>>       

>>>> Do your pods have the twisted cable or the straight?  Both mine have 

>>>> the straight.

>>>>     

>>>>       

>>>>         

>>> Our 8080 pods have the OEM twisted cables.  Our 6502 pods (re: Clay's 

>>> Tempest question) come in both twisted and the flat cables.  I'm 

>>> assuming the flat cable is a non-factory replacement item, but could 

>>> be totally wrong about that.  The 6502 pod that failed just happened 

>>> to have had a flat cable but I'm confident the drive problem was 

>>> unrelated; we found one specific driver output that wasn't going

>>>     

>>>       

>> sufficiently high once plugged into a "real"

>>   

>>     

>>> target board.  It wasn't a general malaise of the address lines like 

>>> you might expect from transmission line losses or higher EMI 

>>> susceptibility due to the flat cable if that's what you are wondering.

>>>

>>>   

>>>     

>>>       

>>>> Are you using a 9010 or a 9100 to drive the pod?

>>>>     

>>>>       

>>>>         

>>> Both...

>>>

>>> Alex

>>> ----

>>> ayeckley at elektronforge.com

>>> www.elektronforge.com

>>>

>>>

>>>

>>>

>>>   

>>>     

>>>