TI 32K PEB expansion problem

[lolof]

I bought a TI PHP1260 last year and just tested it in my PEB today....

 

The test give me errors. See picture.

 

I suppose one or more ram IC are broken...

 

Is there a way to easily know which one on the card are bad ?

 

Thank you very much

 

[+arcadeshopper]

schematics are here: http://www.mainbyte.com/ti99/schematic/schematics.html

 

what I'd do is piggyback known good chips on bank2 and see what fixes it.. 

[lolof]

Thank you for the information.

 

Could you tell me which IC ram are in Bank2 ?

 

I looked at the schematic but honestly I could not understand which one are parts of bank2.

 

Thanks

[+arcadeshopper]

the chips are numbered on the board  I would say..the higher numbers  so looking at the board here I'd say the row nearest the top of the board based on the U numbers

 

Greg

[Fritz442]

41 minutes ago, arcadeshopper said:

the chips are numbered on the board  I would say..the higher numbers  so looking at the board here I'd say the row nearest the top of the board based on the U numbers

 

Greg

Yes, chips 28~35 are for memory C000~FFFF across the top of the board. Chips 28~31 are MSB, 32~35 are LSB.

Lolof do you have a Mini Memory cart?

Edited April 30, 2020 by Fritz442

[lolof]

No, no Mini Memory cart here. Only a FinalGrom99. Can I do something with the FG99 ?

 

I ordered some rams ICs to try the piggyback trick.... I should received them in the next days.

[Fritz442]

Yes try this, load this into Minimem cart and press key '0','1','2','4','8' one at a time. If you can show a screenshot of these.

You can press keys 0~F, but pay special attention to 0,1,2,4,8. When you press '0', anything other that '00' means that bit is stuck on or off.

(EDITED: for added keys)

 

I tried it in the FG-Minimem in the pack but could not get it to load...no reaction on dsk1 drive.

I tried it on '256k MINI MEMORY.zip' version and it loaded fine and worked. 

 

 

MEMWRITE 2.1.zip

Edited October 3, 2021 by Fritz442

[lolof]

Thanks for the help but I am afraid I can't do this.....

 

If I understood good, I should install "256k MINI MEMORY" into the FG99 and then load from it the memwrite file ??

 

I could not find the 256K mini memory.zip in the FG thread....  Where can I find it ? 

 

But,  my main problem should be how to transfer the file ? I am new to the PEB and still have no floppy disks for it.

I could maybe load that file with the TIPI if it's possible but the tipi need the 32k to work if I understood... 

 

I have another card in the PEB, rs232 I think  but I do not know if it's working nor if it's possible and how to transfer file with this connection..... Surely complicate to start with this...

 

I just now the PEB is working OK with a tipi card inside and a 32K outside attached to  the speech Synthesiser. The PEB is connected in this case through a PCB adapter on the external 32K expansion port. (of course without the broken 32K inside the PEB)

 

 

 

Edited May 1, 2020 by lolof

[+Schmitzi]

256k-MM.zip

[Fritz442]

6 hours ago, lolof said:

If I understood good, I should install "256k MINI MEMORY" into the FG99 and then load from it the memwrite file ??

 

But,  my main problem should be how to transfer the file ? I am new to the PEB and still have no floppy disks for it.

I could maybe load that file with the TIPI if it's possible but the tipi need the 32k to work if I understood... 

 

I have another card in the PEB, rs232 I think  but I do not know if it's working nor if it's possible and how to transfer file with this connection..... Surely complicate to start with this...

 

I just now the PEB is working OK with a tipi card inside and a 32K outside attached to  the speech Synthesiser. The PEB is connected in this case through a PCB adapter on the external 32K expansion port. (of course without the broken 32K inside the PEB)

 

 

 

OK, you need to install the '256k Mini Memory' from Schmitzi's post into the FinalGrom, then start Minimem with option '3', then option '1' to Load and Run the Memwrite file.

I don't have a TiPi so I can't help with that, but you will need to get the Memwrite file into the Mini Memory cart. And you must only have the bad 32k card installed.

With no floppy disks, I'm not sure how to get the file there.

[lolof]

Just tried the piggyback trick without success ?

 

Thanks for all the explanations and the files.

 

I have some C64 Floppy disks.... Those can be used with the original PEB floppy drive ?

 

If yes, I could format and write a disk with the file with help of TIPI+external 32Ko. After I could be able to load the file in Mini memory from the floppy drive PEB + only internal 32Ko in PEB..... Does it sounds OK to do ?

 

 

 

[+arcadeshopper]

ok so with a tipi this is easy

 

copy the MEMWRITE file to your tipi drive..   easiest way is the web browser interface at TIPI:9900 

load minimem and hit option 1 and type TIPI.MEMWRITE  

 

[+OLD CS1]

@lolof You can reformat Commodore-formatted disks to work with the TI, and vice-versa.

[+arcadeshopper]

3 minutes ago, OLD CS1 said:

@lolof You can reformat Commodore-formatted disks to work with the TI, and vice-versa.

Definitely can intermix any 40 track soft sectored disk.. they should all work for ss/sd - ds/dd formats 

if you have any concerns use a bulk tape eraser on them before formatting older disk drives sometimes don't have enough "umph" to erase the old format 

 

[lolof]

Thank you. I was able to load memwrite with the TIPI and the 32Ko in the PEB.

I though the TIPI would not work with a broken 32Ko but it worked to load the program. 

 

I just have mistakes pushing "1" (only tried with 0,1,2,4,8)

Here is a screenshot 

 

[Fritz442]

OK with that screen, we'll need to see all key presses if you would. You can also make a small

chart of the results instead of all screenshots.

1C=11

1D=11

and so on...and only the RH column

 

 

Edited May 2, 2020 by Fritz442

[RXB]

Try this is Classic99 using DEBUGGER to see what is going on so run this 2 line program then enter the single line to do same thing you are doing:

 

1 CALL LOAD(8192,0) :: CALL MOVES("RR",4096,8192,8193) :: CALL LOAD(8192,255) :: CALL MOVES("RR",4096,8192,8193)

 

This loads 0 at lower 8K first byte at >2000 then copies that 0 up to >3FFF hex, then loads >FF at same place and copies it up to >3FFF

 

2 CALL LOAD(-24576,0) :: CALL MOVES("RR",24575,-24576,-24575)

 

This loads 0 at upper 24K first byte at >A000 then copies that 0 up to >FFFF hex

 

CALL LOAD(-24576,255) :: CALL MOVES("RR",24575,-24576,-24575)

 

Now as any program in 24K is erased due to the line 2, this line above has to be entered manually instead. It loads the >FF like above did 0.

 

Using RXB you can also debug memory blocks too.

[+dhe]

Wasn't there a basic program that would tell you what chip failed?

[lolof]

Thanks for all the replies and help.

 

Fritz442 could identify the exact broken Chip with help of minimem/easybug

 

This was U31. Piggyback did not work in this case,I tried several times.  As suggested by Fritz, I replaced the bad U31 with a new one  and the card is working now.?

 

Happy to have the 32Ko working in the PEB ? 

 

 

 

[JB]

Hooray!

[Fritz442]

Hey guys, I replaced the Memwrite.zip file in post #7 and here to version 2.1. It detects chips a bit better.

Also included a jpg of the chips# vs bits#. Helps tell which ram chip goes with the stuck bit.  

 

MEMWRITE 2.1.zip

 

For Minimem Cart.

Edited October 3, 2021 by Fritz442