Found these inside a non-working 71B

[Dave Frederickson]

(03-17-2018 01:41 AM)Paul Berger (Canada) Wrote:  I got an Andonstar, the silver tube model, I see they have some others now including one that has a tiny screen built in. It works pretty good but the stand is a bit shaky, jumps around a bit much when you are trying to focus or adjust height. I have yet to try building under it but I do think it will work ok.

Unavailable on Amazon, but it looks like eBay has some,

https://www.ebay.com/itm/Andonstar-2MP-U...0984958025

Is this the model? What's the long tube for? Oh! Never mind.

Here's the mod.

Click to zoom


Dave

[MikeSD]

Here is the FORTH Assembler Module. I can't see anything out of the ordinary. Wonder if there was some jumper that was present that got removed when this was cleaned up.

Anyway, when 1-7, 8 and 13 are used, the system won't power up. I'll be checking voltages tomorrow.

[Paul Berger (Canada)]

(03-17-2018 02:08 AM)Dave Frederickson Wrote:  

(03-17-2018 01:41 AM)Paul Berger (Canada) Wrote:  I got an Andonstar, the silver tube model, I see they have some others now including one that has a tiny screen built in. It works pretty good but the stand is a bit shaky, jumps around a bit much when you are trying to focus or adjust height. I have yet to try building under it but I do think it will work ok.

Unavailable on Amazon, but it looks like eBay has some,

https://www.ebay.com/itm/Andonstar-2MP-U...0984958025

Is this the model? What's the long tube for? Oh! Never mind.

Here's the mod.



Dave

Thanks I try that tomorrow. Yes that is the model the long plastic tube is so you can stick it into liquids, just one of a number of "useful" accessories included.

Edit: Ok I must have misread something the tube is not sealed on the end and I see the eBay ad suggests other useful applications of that tube ......

Paul

[Didier Lachieze]

(03-17-2018 01:41 AM)Paul Berger (Canada) Wrote:  I got an Andonstar, the silver tube model, I see they have some others now including one that has a tiny screen built in. It works pretty good but the stand is a bit shaky, jumps around a bit much when you are trying to focus or adjust height. I have yet to try building under it but I do think it will work ok.

The Andonstar v160 has a good review from Elektor magazine.

[rprosperi]

(03-17-2018 03:34 AM)Paul Berger (Canada) Wrote:  Edit: Ok I must have misread something the tube is not sealed on the end and I see the eBay ad suggests other useful applications of that tube ......

... some of which are a real pain in the ass.

[Dave Frederickson]

(03-17-2018 03:32 AM)MikeSD Wrote:  Here is the FORTH Assembler Module. I can't see anything out of the ordinary. Wonder if there was some jumper that was present that got removed when this was cleaned up.

Anyway, when 1-7, 8 and 13 are used, the system won't power up. I'll be checking voltages tomorrow.

I believe Raymond made this observation, there's battery corrosion residue on the module. That needs to be removed with a vinegar solution or DeoxIT D100 (red). Check for any shorts between the pins with a meter. Also, its possible that the corrosion may have spread under the encapsulation and this is what killed the calc in the first place.

Dave

[MikeSD]

(03-17-2018 05:40 PM)Dave Frederickson Wrote:  

(03-17-2018 03:32 AM)MikeSD Wrote:  Here is the FORTH Assembler Module. I can't see anything out of the ordinary. Wonder if there was some jumper that was present that got removed when this was cleaned up.

Anyway, when 1-7, 8 and 13 are used, the system won't power up. I'll be checking voltages tomorrow.

I believe Raymond made this observation, there's battery corrosion residue on the module. That needs to be removed with a vinegar solution or DeoxIT D100 (red). Check for any shorts between the pins with a meter. Also, its possible that the corrosion may have spread under the encapsulation and this is what killed the calc in the first place.

Dave

No corrosion anywhere. The calc wasn't killed by corrosion. I removed all the mods, fixed a broken display wire and it fired right up. This is a very clean machine, from that respect. There is some residue on the chips but that was the potting stuff they used to bond it into the unit. I've cleaned most of it off.

I have already buzzed from each pin to every other pin, and from pins to ground and power. Only 12 and 13 are shorted together and you can see that in the photo. I have also buzzed to see that there are no cracks or breaks between the pads and any of the via traces to the components. So far all is ok.

I think I might install it in my test unit that is unmodified, and install it in a port position, to see if it works. That eliminates all the other wiring in my original unit. That should tell me if it's working.

[Dave Frederickson]

(03-17-2018 08:37 PM)MikeSD Wrote:  

(03-17-2018 05:40 PM)Dave Frederickson Wrote:  I believe Raymond made this observation, there's battery corrosion residue on the module. That needs to be removed with a vinegar solution or DeoxIT D100 (red). Check for any shorts between the pins with a meter. Also, its possible that the corrosion may have spread under the encapsulation and this is what killed the calc in the first place.

Dave

No corrosion anywhere. The calc wasn't killed by corrosion. I removed all the mods, fixed a broken display wire and it fired right up. This is a very clean machine, from that respect. There is some residue on the chips but that was the potting stuff they used to bond it into the unit. I've cleaned most of it off.

I have already buzzed from each pin to every other pin, and from pins to ground and power. Only 12 and 13 are shorted together and you can see that in the photo. I have also buzzed to see that there are no cracks or breaks between the pads and any of the via traces to the components. So far all is ok.

I think I might install it in my test unit that is unmodified, and install it in a port position, to see if it works. That eliminates all the other wiring in my original unit. That should tell me if it's working.

In the pic in Post #122, there's green stuff between the traces near the top of the long vertical row of vias (holes). That green stuff is battery corrosion.

[MikeSD]

(03-17-2018 08:51 PM)Dave Frederickson Wrote:  [quote='MikeSD' pid='93189' dateline='1521319072']

In the pic in Post #122, there's green stuff between the traces near the top of the long vertical row of vias (holes). That green stuff is battery corrosion.

It might look like corrosion, but without a chemical analysis, I think it's the potting stuff used to bond the surface to the calc. I had a ton of it on the back and it took forever to get it off. It does have a greenish tent to it. But that stuff just wiped off with a little goop remover.



However, the chip may be dead. Here are the connections I used, to connect to my other calc and it froze too, but with the cursor displayed. Pins1-8 and 13 were used.

Since the chip isn't repairable, about the only thing I can do is verify continuity between top and bottom pads, to make sure there isn't any opens there. Looks like the best chip may be belly up, unless there is a necessary missing connection.

Oh wait! I just realized that this was wired as a Port, in my test unit. Ports use pin 10, 11 and 12 also. Pin 12 is tied high though. Any chance those may be causing it not to behave properly as a port device? Wonder if those were also needed when wired into the port zero string? And does the Math also need any of those?

[rprosperi]

2 thoughts:

1. The 2 tabs just to the right of the HP logo sure look like they had been connected in the past. Is it possible that needs to be connected?

2. The Forth ROM contains 2 ROMs, 32K hard-addressed at E0000 and 16K soft-addressed by the OS Config. Could this need an additional line connected?

[Paul Berger (Canada)]

(03-17-2018 09:50 PM)MikeSD Wrote:  

(03-17-2018 08:51 PM)Dave Frederickson Wrote:  [quote='MikeSD' pid='93189' dateline='1521319072']

In the pic in Post #122, there's green stuff between the traces near the top of the long vertical row of vias (holes). That green stuff is battery corrosion.

It might look like corrosion, but without a chemical analysis, I think it's the potting stuff used to bond the surface to the calc. I had a ton of it on the back and it took forever to get it off. It does have a greenish tent to it. But that stuff just wiped off with a little goop remover.



However, the chip may be dead. Here are the connections I used, to connect to my other calc and it froze too, but with the cursor displayed. Pins1-8 and 13 were used.

Since the chip isn't repairable, about the only thing I can do is verify continuity between top and bottom pads, to make sure there isn't any opens there. Looks like the best chip may be belly up, unless there is a necessary missing connection.

Oh wait! I just realized that this was wired as a Port, in my test unit. Ports use pin 10, 11 and 12 also. Pin 12 is tied high though. Any chance those may be causing it not to behave properly as a port device? Wonder if those were also needed when wired into the port zero string? And does the Math also need any of those?

Pin 10 is IR14(Interrupt 14) it would not normally be used by memory devices. Pin 11 is OD in port 1 taking it high disables the internal ROM and is Halt on the rest of the ports this pin would not be used by memory devices except ROMs that take over from the internal OS ROM when plugged into port one such as the diagnostic ROM. Pin 12 is an active low interrupt line. On the plug in modules this pin is normally connected to ground, and if you look at the connectors for the ports you will see a round pad near the outside edge, then a gap and further back the pin would contact a widened ground pin. what this does is cause a momentary interrupt when a module is inserted or removed which notifies the OS so that it can do what it needs to to deal with the event. When you are hard wiring the module in side this pin does not need to be connected to anything.

Off topic, to you have any spare parts for a 71B? I am looking for a top half, it does not need to be functional all I really need from it is the circuit board.

Paul.

[Dave Frederickson]

(03-17-2018 09:50 PM)MikeSD Wrote:  Oh wait! I just realized that this was wired as a Port, in my test unit. Ports use pin 10, 11 and 12 also. Pin 12 is tied high though. Any chance those may be causing it not to behave properly as a port device? Wonder if those were also needed when wired into the port zero string? And does the Math also need any of those?

According to the H/W IDS, Ch. 6.1, ROM Pin Descriptions, those other signals aren't needed. OD could be connected, but it's only necessary if you want the Service Module to disable the ROM.

Dave

[MikeSD]

No solder jumpers were removed by me.

Trying to keep it simple.

I assume it was working at one time. So, I assume the main wiring was correct and what I'm using (1-7, 8 and pin13). Took photos to preserve original wiring.

All other chips seem to work fine, including the 71B. So, nothing traumatic happened to it.

Either there is something I'm misunderstanding about this or the FORTH might be dead. I've wired it in the port 0 string and when it's there, the 71B shows no signs of life. Nothing on display. When I put it in my other 71B as a port device (port 4), I see a frozen cursor and no other sign of life. Hard wiring it as Port 4 chip seems to suggest it's dead. Pin 12 us connected to pin 13, and pins 10, 11, 12 are assigned on port. I dont have thise wired. wonder if they are needed. Can't hurt to try at this point.

Not looking good.

[MikeSD]

'Paul Berger Wrote:Off topic, to you have any spare parts for a 71B? I am looking for a top half, it does not need to be functional all I really need from it is the circuit board.

Paul.

I have some spare boards. I know I gave about 6 non-working units and several lower half boards. Seems likely if I have lower half boards, I probably have upper too.

What kind do you need? Plastic back versions or metal back versions. Or if you need something specific let me know and I'll see what I have.

In addition to whole non-working units, I have these for parts. Have case parts and lower boards too.

[MikeSD]

(03-17-2018 02:08 AM)Dave Frederickson Wrote:  Here's the mod.

Click to zoom


Dave

Does this mod alone allow two 32k to be configures as a single 64K? The programmer has a switch action to do that. I assume this is a photo of your programmer. That switch must factor into operation, which makes me think something else is required. Like adding or removing a ground to do either.

[Paul Berger (Canada)]

(03-18-2018 12:03 AM)MikeSD Wrote:  

'Paul Berger Wrote:Off topic, to you have any spare parts for a 71B? I am looking for a top half, it does not need to be functional all I really need from it is the circuit board.

Paul.

I have some spare boards. I know I gave about 6 non-working units and several lower half boards. Seems likely if I have lower half boards, I probably have upper too.

What kind do you need? Plastic back versions or metal back versions. Or if you need something specific let me know and I'll see what I have.

In addition to whole non-working units, I have these for parts. Have case parts and lower boards too.

It's a metal back that I am looking for the upper for.

Paul.

[Dave Frederickson]

(03-18-2018 01:03 AM)MikeSD Wrote:  Does this mod alone allow two 32k to be configures as a single 64K?

This is all that was required to mod an HHP module.

Quote:The programmer has a switch action to do that. I assume this is a photo of your programmer. That switch must factor into operation, which makes me think something else is required. Like adding or removing a ground to do either.

There is the cut trace, which we can presume was connected to VCC in order to set the LCIM bit in the module's config buffer entry. The switch drives the signal to either 6.5 or 0V, probably through some additional circuitry.

Dave

[Paul Berger (Canada)]

(03-18-2018 02:08 AM)Dave Frederickson Wrote:  

(03-18-2018 01:03 AM)MikeSD Wrote:  Does this mod alone allow two 32k to be configures as a single 64K?

This is all that was required to mod an HHP module.

Quote:The programmer has a switch action to do that. I assume this is a photo of your programmer. That switch must factor into operation, which makes me think something else is required. Like adding or removing a ground to do either.

There is the cut trace, which we can presume was connected to VCC in order to set the LCIM bit in the module's config buffer entry. The switch drives the signal to either 6.5 or 0V, probably through some additional circuitry.

Dave

Just past the top right of Dave's picture there are two square pads that I am guessing where originally intended for a surface mount capacitor. The left most one is ground and a convenient place to connect to if you do not intend to include a switch. I did that mod on a pair of modules built into my 71B.

Paul.

[cortopar]

Having just bought what I believe is this unit from Mike, if anyone has new ideas on getting the Forth ROM working, I’d appreciate hearing them.

Would putting this in a sacrificial case (to install in one of the front ports) be worthwhile?

[Dave Frederickson]

(05-12-2018 11:55 PM)cortopar Wrote:  Having just bought what I believe is this unit from Mike, if anyone has new ideas on getting the Forth ROM working, I’d appreciate hearing them.

Would putting this in a sacrificial case (to install in one of the front ports) be worthwhile?

Based upon my experience, if it fixes the module then it was worthwhile. If it doesn't, then no.