Newbie rebuild - 98 orig membrain/CRT- small "e"' all the time on the input line....

Newbie rebuild - 98 orig membrain/CRT- small "e"' all the time on the input line....

Hi everyone... sHOUT OUT: Happy Father's Day a bit early to all Dads.

Ok - suddenly getting a small 'e' ... 2 , 4, or more at a time.. they just pop in every sec or so. Pulling boards in the back to get to the keypad cable to clean and re-seat. The small "e" does work from the keypad. Seems like a good depress. in short, does not feel like the E is bad. raised bubble and nice depress. So... it's a long ribbon cable. wondering if there is anything to prove it's the keyboard? or the cable or what folks have seen w/ this situation.

thanks all!

I've seen a lot of issues with the Haas key pad. I can't comment on the specific case of an "e", but I've replaced several key pads for various issues.

Thanks. As a general note for others... I've found that manuals vary significantly in content and overview. This image came form the 99. I bounce from 96's to 99's and other all the time to compliment the overall service info on our unit. Passing along for the orig Ops pendant as a block diagram. Going to dig in today.

So here is the reply from the HFO on the small 'e' insertions... OUCH and NFW.

Unfortunately your issue is your processor which would require 93-4421 $14,995 plus labor to install

This will change your hardware to 2010 new monitor and usb drive. Other than that the machine will function as it always has not improvement in speed or repeatability.


I did find this posting set (below) where folks mention both a CPU board or a keypard... and we know the current issues w/ CPU boards. While it's not the Mororola CPU itself, there are a lot of TTL latches for the data and address buss... plus the large Xlinx (sp?) IC's on there. This is gonna suck! it's just a Dad and his kid in the garage.

https://www.practicalmachinist.com/vb/haas/screen-has-lower-case-es-going-across-cursor-area-200498/

There are quite a few things to try before the 15k option. More than likely the Hfo doesn’t have any idea as the techs really don’t know the old systems like the newer.

#1 Check or replace the power supply.

#2 Check all the supply connections. Re seat the parallel flex cables.

#3 replace the video pcb anyway.

#4 You could try having the Hfo reload the software.

#5 map and and check the keypad yourself to be sure it isn’t actually the membrane. It is going to be a row and column type system.

#6 if brave, re seat and clean some of the socketed ic’s. If the wrong ones of course, you’ll be reloading Params at minimum.

countryguy said:

Unfortunately your issue is your processor which would require 93-4421 $14,995 plus labor to install

Click to expand...

Not likely but an easy way to check is to disconnect the keypad ribbon cable once from each end and see it the 'e' still appears. Then you know if it is the keypad or cable. I have an older machine ('91) but have had no problems with the keypad. As your reference said, it could be a grounding problem. The keypad is a simple matrix switch which gets decoded by the processor.
I know someone who has made replacement keypads if that is the problem.

Thanks everyone! We'll go into this a few different ways now!!! Many thanks. Checking power supplies next. Good call! in the 80's I was an Old Aerospace EET so no fear diving into this thing at the logic level. A few things: I found a source for a old CPU board swap program. $3K if that's the root cause. Wont really be digging in til after. (gulp)... Hay is up in the barn. ohh the fun here.
Also- I have a o-Scope/Logic probe setup from Diligent. Very cool btw way. A shout-out on it's capabilities here: Digilent Analog Discovery 2 from SparkFun! - YouTube Student Pricing (if a student or teacher) is 40% off! Plus, I have a can of Freeze spray on the way. Cannot tell ya how many bad things I've found w/ a can O freeze spray. :-)
I think I can monitor the serial keyboard input and see if the 'e' is coming from the bubble keys I'll assume. Maybe even see what hits the ribbon output going back to the serial Comms Again, learn mode- active. LOL.

I had one machine spitting out some letter and a keyboard change fixed.

Had another that required a processor board after a good long time playing around with it, cleaning sockets, new ground, hard boots, new keyboard. I went a good two years before it gave up the ghost.

I wasn't happy at the few grand it cost...but glad it was before they ran out of old stock. Still I had a bunch of stupid quirks since it was replaced...odd alarms and quirky moves.

15K isn't a joke and it is not a repair at that price...its a Sunsetting move, placing you over a barrel without the aid of vasoline at that price.

countryguy said:

Hi everyone... sHOUT OUT: Happy Father's Day a bit early to all Dads.

Ok - suddenly getting a small 'e' ... 2 , 4, or more at a time.. they just pop in every sec or so. Pulling boards in the back to get to the keypad cable to clean and re-seat. The small "e" does work from the keypad. Seems like a good depress. in short, does not feel like the E is bad. raised bubble and nice depress. So... it's a long ribbon cable. wondering if there is anything to prove it's the keyboard? or the cable or what folks have seen w/ this situation.

thanks all!

Click to expand...

If i recall everything correctly the problem could be caused by blown C40 capacitor on the processor board. (I think its located on the right side of the board somewhere)

That would be amazing if C40 does it.
I've been told about the low voltage PS and the output caps going dry. (all on order today via Amazon prime :-) May as well get the dry caps replaced. and also was just told making some calls about some odd cap on the CPU board causing lC chars (among other things)[/U] (so this helps cement that one).

I have attached some pics. Things are adding up and I want to ensure we solve this for the masses out there that are getting asked to spend 3,000-5000 dollars for a product that is very busy in the resale space. Not looking for PC posting on old/obsolete faults- I get that.. but we're here to help each other when all you can afford is the low end and try to make a living w/ sweat equity and brute determination. so thanks everyone!

So... The parts in/around the CPU board where the ribbon cable:
PIC 1- The 44PLCC IC 68C681 is a Dual Async RxTx DUART device. square gull-wing thing. Part of the serial comms settings chip.
PIC 2- the ADM238 is a QUAD 232 Rvcr/Transmitter IC. (line driver) The 4 in-a-line little yellow SM (surface mount) caps in the pic below. C40 is the most right and connects to pins on the ADM238 IC. Which is part of the circuitry that communicates back/forth via the ribbon cable to the Ops Pendant
PIC 3- the last picture is the two Caps on the board where the power-supply input is connected. Just making sure form the post above where lower right, is mode middle-right, which is where C40 resides. (image 2).
The pin outs for the 232 Rx/Tx show that C40 connects to the +10 to -10 invertor section. (Pic 4) below. :-) Wish us luck!

Pic 1


Pic 2


Pic3


Pic 4

The parts list and supplys.

CPU board:
1) the 232 Driver: PN# ADM238LJRZ-ND Digikey.com direct replacement for the LJR (had lead) and the new replacement. $4.00

2) C40, the tantalum cap. Amazon: MCIGICM 1uf tantalum capacitor, 1mF Molded Tantalum Capacitors 25V 126 (3216 Metric) 8 Ohm: Amazon.com: Industrial & Scientific $10.00 pack of 25.

The power supply caps:
1) qty 2 needed- 390uf 35v: Aluminum Electrolytic Capacitors - Leaded 35Volts 39uF 1X2 2% 5Ls: Amazon.com: Industrial & Scientific

2) qty 1 needed- 470uv, 200V : Amazon.com: NICHICON LLS2D471MELY CAPACITOR ALUM ELEC 47UF, 2V, 2%, SNAP-IN: Industrial & Scientific

3) qty 6 needed- 1000uf 35V : 6 pcs Panasonic FR Series Capacitors - 35V 1uf Ultra Low ESR: Amazon.com: Industrial & Scientific

4) qry 2 needed- 4.7uf 63V :Aluminum Electrolytic Capacitors - Leaded 63volts 4.7uF 6.3x11 2% 2.5LS (5 pieces): Amazon.com: Industrial & Scientific

5) freeze spray : https://www.amazon.com/gp/product/B07CCHPC1R/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

6) side cuts (mine are old and dull.. to snip SOIC SMD's you need them really sharp). : https://www.amazon.com/gp/product/B072WS3M9H/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

7) ESR meter for checking caps... $8... no brainer. overdue! https://www.amazon.com/gp/product/B00RM0R05O/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

8) you will need #30 gauge solder. thin as a hair! and the finest point solder tip/pencil you can obtain.

Will be a few day's while things show up and we dig in! Again, did this all in the 80's/90's.... we'll get this into a set that about anyone can do if we can get this to come common failure parts. I'm not paying 3-5K for a .25cent cap or $4 IC.

For the old mates' SHOTGUN... (rip & replace some known area high failure components) then yell BINGO when it runs after that.

A little better pricing at Mouser. I get parts in about 4 days with regular mail. Other options available.
A hot air soldering station works well for removing/replacing SMD parts. Mine has both the iron and air gun.
Good pointer on the ESR meter.

Have you looked at how the keyboard matrix is being scanned. Understanding how it works might prevent you from spending time and money.

A keyboard matrix can be polled or interrupt driven. My explanation will use a active low signal.

1. A polled system will drive all rows low for a few msec then read the port register for the columns. If the column port register indicates a change then the key press is valid and the key can be decoded in a lookup table using the column and row data. A two key lockout is usually used at this time to ignore a multiple key press.

2. A interrupt drive system will only scan the keyboard when one key is pressed and not waste time otherwise.

What does the keypad look like? The width of the keypad cable?

Whats your software version? I happen to have a spare CPU board I will let go for a hell of a lot cheaper than 15k I do however feel that the issue is keyboard related. Seen it before. These keypads are known for phantom presses when there start to fail. Thermal expansion/ contraction is all it takes. However, I have seen the CPU board do weird stuff when failing too so its very hard to say without having it on the test bench. Do you have any other issues with the machine? I have seen bad fast static ram cause craziness with random issues. Normally when its a CPU board issue there are more problems than just one. As magno_grail stated. Unplug the ribbon to the keypad and see if you get any key presses leaving it be. You can also bypass the boot software at power on by holding the "prog/conv" key down and powering on the machine. This puts it into boot loader mode. Don't enter anything here but just watch the screen. See if they still get pressed.

rons said:

What does the keypad look like? The width of the keypad cable?

Click to expand...

If you detached the key board ribbon able you could use a simple ohm meter. Find out which key closures allow a connection from the column to row. The Hass keyboards I've seen look a little complicated but some keyboards can be figured out by looking on the reverse side of the circuit board where the keys are mounted on.

Sometimes when a hardware problem exists it can cause the software to operated past a boundary condition, then things operate weird. Such as a row or column register holding wrong data. If the situation is studied the reason for the weird operation is always explainable.

I was looking at the cost of replacement keyboards. Considering their size the prices seem reasonable.

CPU board spare. Sent you a PM....

Hi Sent you a PM on the CPU board. Do you want the Rev or firmware noted on my Eeprom or just whats on the OS when it boots?

OS when it boots. If you have not done so, backup your parameters, settings, macros, programs (including the 9000s) now.

Short update... Came back on Thursday night, Friday, 0500, soldering pencil in hand and I was soldering in parts. The power supply cap replacement went fine. Hard to get the old parts out w/ solder-wick, so I just heated and pulled out a side at a time. Then dremeled the thru-holes the rest of the way. On the CPU, C-40 was replaced on the CPU board as part of the possible known-failure items that can cause this. It is hard to get off w/o a hot air station, but I did get it off. Pulled up 1 trace a bit and used #30 gauge wire to wire back to the IC. Again, C40 is for the -10 supply on the 232 IC.

After 3 hours getting all the boards and cables back in, I was able to get her to power back up. Booted and ran for nearly 6 hours today. No 'e's Looks promising!!! In the past- w/i 20-30mins the 'e's were all over. a 27cent cap for a fix. will take that anyday.

Mocon is 12.07 and Haas 9.49 when it boots.

Instead of trying to use solder wick to open the holes, use a solder vacuum pump. They are inexpensive. Cock the pump, heat the solder then apply the tip and trip the pump. It will suck out the solder from the holes. Less possibility of damaging the circuit board or getting swarf in the circuitry..

Yep.. Good point. Honestly, I have several suckers. An older (better) unit and newer small hole. Neither pulled the hole clean on these huge (-) pad 2 layer sides. I did not want to go overheating either. Honestly, after 25 years out of the EET repair biz, I was rusty!! But we got it done. Hopefully this thread series can help some folks down the road w/ options, tips, parts, possibly solutions, and techniques for semi-skilled. You definitely need to be careful if you take this on yourself. You could probably show this thread series to someone w/ board level skills and have them do it for a reasonable price. Someone listed in local Maker/Hack-a type sites. The objective was simple- group-level chatter on ancient Has CPU board and the 'lower case' chars on the cursor. (when NOT the keypad). THANK You to everyone for the help and support of this site and Haas forum. Been nothing but 'net' from ya'll.