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I make Kazzo UNROM cart according to the description of this page:
https://osdn.net/projects/unagi/wiki/flash_74161_en

Checked everything thoroughly, I do not know why you do not want to work. PCB has a DIP32 socket - if the memory is programmed external programmer it all works ok, but do not want to run the Kazzo programmer (I used the original game PCB - exactly HCV-UNROM-03, two types of flash memory have been tested - SST39SF020 and W49F002)

Was it tested at all, maybe UNROM with 74xx00 has not been tested, or am I doing something wrong?

In the wiki page, there's this comment:

Devices that support A0-A10 command addresses are supported (e.g. AM29B040B). Unfortunately this type of board is unable to allocate A0-A14 command addresses.

Unfortunately, the SST39SF0x0 and W49F00x that you've tested are types that requires 15-bit command addresses.

So just change the flash memory on AM29B040B and it will work?

I would naïvely assume yes.

UNROM
Banks
CPU $8000-$BFFF: 16 KB switchable PRG ROM bank
CPU $C000-$FFFF: 16 KB PRG ROM bank, fixed to the last bank.

39SF0X0 flash command:
5555 AA
2AAA 55
can not map to UNROM at a same time.

But for 29F0X0, command is
555 AA
2AA 55
It's OK for UNROM.

also you can not use 39SF0X0 for MMC1(chr chip).

Thanks for the information. Are there any compatible flashes with AM29Fx0 that can be used in UNROM?
And in fact you're right, the MMC1 did not want me to program CHR.

The so-called UNROM 512 board contains a 74LS139 that hides writes to $C000-$FFFF from the flash memory. It's essentially free because the board needs the other half of the '139 to drive /OE high when R/W is low, as /OE overrides /WE on flash, unlike 6264/62256 SRAM. So you'd control A14 of the memory with $C000 bit 0.

AM29F040B works with UNROM Thanks for the info.

From what I've noticed, it's very similar to the AM29F040B is the Amic A29040B flash. It is hard for me to verify 100%, because I only guess: is the problem in KAZZO is the size of sectors in FLASH memory? AM20F040B has a size of 64KB (A0-A15)? AMIC is similar and also has "8 uniform sectors of 64 Kbyte each"

http://www.farnell.com/datasheets/34117.pdf

This site was mentioned about this AMIC, but it is in Japanese it's hard for me to translate it reasonably:
http://overpotentness16.rssing.com/chan ... latest.php

It's not the sector size.

It's very specifically the number of address lines used for the command sequence.

For the SST39 series, the command addresses are 0x5555 and 0x2AAA. This requires 15 address lines, and the flashable design used by the Kazzo only affords 14 address lines (it can't change the PRG bank in the middle of issuing the sequence)

On the other hand, for the AM29 series (and apparently this A29 series too), the command addresses are 0x555 and 0x2AA. This only requires 11 address lines, and so the programmer can issue writes to flash without needing to change the PRG bank in the middle.

I checked DIL32 AMIC A29040B-70 and works with UOROM (programming works).

In currently, SST39SF040 is easy to find DIP32, 5V, 512Kx8 flash memory. The command addresses range of SST39SF040 is too wide for CPU area ROM on the UNROM and MMC1.
Ten years ago, AM29F040B was easy to find DIP32, 5V, 512kx8 flash memory...

I have checked AMIC A29040B and Macronix MX29F040C as alternative of AM29F040B. These flashes works good. MX29F040C don't have DIP32 version. Someone uses MX29F040C on the Famicom cartridge with TSOP(I)32 to DIP32 adapter PCBs.
I think the adapter PCB is better than DIP32 devices. It can be soldered without removing the ROM. It requires arrange CE# pin on the ROM.