HELP: repair my ML 38s

[cmkc]

hi,
my ML 38s preamp damage by wrong voltage, i check it the line part is good, problem is on logic control, the logic have three programable ic, if once damage must cant power on, one is cpu(mc68hc11a) one is eprom 27c512, one is peel18cv8, the problem is on peel18cv8 because its very hot, and cannot read data use my universal programmer, 27c512 is ok and have read the data, the cpu i check ref voltage also is ok
now i have new peel18cv8 but have not the inside data, please help me where can get the data, i have ML 332 also use peel18cv8 to logic control, i use 332 18cv8 in 38s, the panel have respond but not proper work, i think 18cv8 is differ version because the label code is differ
please mail me if someone have 38 or 380 18cv8 data code, i can share 38s eprom data and 332 18cv8 data,
thank you vey much
steven

[destroyer X]

if regulators gone, then a lot of chips and microprocessors gone too.

regards,

Carlos

[cmkc]

Originally posted by destroyer X

if regulators gone, then a lot of chips and microprocessors gone too.

regards,

Carlos

the regulators is ok, all parts seems is ok only 18cv8 damage

[cmkc]

please help

[jaycee]

The only way youre going to be able to get this data is to convince someone with the same unit to pull the chip and read it out.

Alternatively see if the manufacturer will help, but their answer will likely be "no".

[Algar_emi]

The part you're referring too, the 18cv8 is a PAL, not an EPROM or ROM, used to complete the logic interface, it is used to remove data processing from this rather old and slow processor the 68HC11. It is used for example to read the optical encoder uses as volume control interface.

It would be impossible to get this PAL IC, I was never able to fix a damaged PCB that has this problem. I tried on two nice 38S PCB that P.Daniel has but with no luck. Without this PAL IC, the board is useless. Sorry.

SB

[cmkc]

Originally posted by Algar_emi
The part you're referring too, the 18cv8 is a PAL, not an EPROM or ROM, used to complete the logic interface, it is used to remove data processing from this rather old and slow processor the 68HC11. It is used for example to read the optical encoder uses as volume control interface.

It would be impossible to get this PAL IC, I was never able to fix a damaged PCB that has this problem. I tried on two nice 38S PCB that P.Daniel has but with no luck. Without this PAL IC, the board is useless. Sorry.

SB

hi, Algar_emi
as i know, 18cv8 is "PROGRAMMABLE ELECTRICALLY ERASABLE LOGIC DEVICES"
http://hk.mouser.com/Cart/Additional...part=5-0505-48
also it can be read write data use my universal programmer, i have test easy my ml332 18cv8 then write it again, its ok, Mr Algar_emi, how do you think if i copy another 38s 18cv8 data in my new 18cv8, will it be work?
thx

[cmkc]

oh...i check the 18cv8 datasheet, it have a eeprom security bit, if active will cannot read data, but i can read ture data in my ml332 18cv8, that mean ml332 18cv8 is inactive security bit? Algar_emi, have you try raed the good one ml38 18cv8? may you help me try to read? maybe all ml product not protect the 18cv8

[Algar_emi]

Yes, the security bit. This is why I never tried to unsolder this IC, afraid that I could damage it and/or the PCB (those ML38 PCB are very tricky to work with, the pin's pads are so thin, they can be easily damaged), and not be able to read it at the end.

[cmkc]

hi,
for me unsolder is esay even BGA i.c, the new one 18cv8 (smd) is ready, just wait the good 18cv8 data to copy , i believe 18cv8 data is non protect, if have protection, my china friend can help me crack it easy, in china its just easy job