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EPROM emulators? [message #10040]

Sat, 30 July 2022 13:09

mikesmith
Messages: 80
Registered: March 2018

Member

I'm looking for an (E)EPROM emulator, ideally capable of emulating devices up to 512Kx8.

So far the only commercial product I've been able to find is the Momik memsim2. I ordered one; it doesn't work right(1) and the vendor is unresponsive.

Are there any others out there that are still available and more functional? I'm sure I could build something, but I'm already neck deep in tool dependencies and really don't want to add another...

(1) It doesn't entirely conform to the protocol that the open-source tools for it suggest it should, though I was able to sniff the USB protocol and copy what their Windows software does. It also doesn't seem to be able to emulate a 512K EEPROM without cable butchery. All survivable I guess, but still...

[Updated on: Sat, 30 July 2022 15:05]

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Re: EPROM emulators? [message #10047 is a reply to message #10040]

Mon, 01 August 2022 05:56

stevemoody
Messages: 13
Registered: February 2019

Junior Member

Many years ago I used to use a Dataman S4 for an emulator. Good devices but seem very expensive these days.

A few years back I did start working on my own EPROM emulator but didn't get very far with it. I have a 6809 based board that I've designed, maybe it's a good time to reive the project as it would help speed up development there.
https://hackaday.io/project/167155-eprom-emulator

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Re: EPROM emulators? [message #10051 is a reply to message #10040]

Tue, 02 August 2022 03:37

tapy
Messages: 17
Registered: June 2021

Junior Member

I have two MEMSIM2s and they work without problems in this configuration. I would advise you to check the emulation plug as that is where most problems are, often adding a precision socket and using such a sandwich helps.

The manufacturer will not answer, as far as I know they have gone out of business. It's a shame, because they also produced quite good programmers, but they probably couldn't stand the Chinese competition.

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Re: EPROM emulators? [message #10082 is a reply to message #10051]

Fri, 12 August 2022 23:46

mikesmith
Messages: 80
Registered: March 2018

Member

Quote:

I would advise you to check the emulation plug as that is where most problems are, often adding a precision socket and using such a sandwich helps.

Not *entirely* sure how that would help the lack of USB serial output. Cool

Quote:

The manufacturer will not answer, as far as I know they have gone out of business. It's a shame, because they also produced quite good programmers, but they probably couldn't stand the Chinese competition.

They were quite happy to take my money off eBay and send me a new one; I guess that could easily be some zombie fulfilment service rather than the manufacturer. As for Chinese competition, which one?

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Re: EPROM emulators? [message #10086 is a reply to message #10082]

Sun, 14 August 2022 16:18

tapy
Messages: 17
Registered: June 2021

Junior Member

mikesmith wrote on Fri, 12 August 2022 23:46

Not *entirely* sure how that would help the lack of USB serial output.

You implied a lack of 512kB EPROM emulation capability, and I took playing around with the serial protocol as an attempt to learn it. My devices emulate the 27040 quite often and I have had no such problem.

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Re: EPROM emulators? [message #10087 is a reply to message #10086]

Sun, 14 August 2022 18:09

mikesmith
Messages: 80
Registered: March 2018

Member

tapy wrote on Sun, 14 August 2022 16:18

mikesmith wrote on Fri, 12 August 2022 23:46
Not *entirely* sure how that would help the lack of USB serial output.
You implied a lack of 512kB EPROM emulation capability,

EEPROM. The 39F040 parts have the MS address signal on a different pin, and whilst the hardware looks like it might be able to handle it, the device doesn't cope.

Quote:

and I took playing around with the serial protocol as an attempt to learn it. My devices emulate the 27040 quite often and I have had no such problem.

I understand the serial protocol as implemented in various tools on github. It's just that the unit I have doesn't conform. Cool

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Re: EPROM emulators? [message #10091 is a reply to message #10087]

Sun, 14 August 2022 23:26

tapy
Messages: 17
Registered: June 2021

Junior Member

I don't think you'll find a device that is designed to emulate flash, which can be reprogrammed in circuit far faster than it takes to transmit serial to this EPROM simulator. EEPROM and Flash were developed for this purpose.

PS. The company seems to be up and running after all, as I see they have resumed sales. You would be best advised to contact them Smile

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Re: EPROM emulators? [message #10092 is a reply to message #10091]

Mon, 15 August 2022 09:54

mikesmith
Messages: 80
Registered: March 2018

Member

Quote:

I don't think you'll find a device that is designed to emulate flash, which can be reprogrammed in circuit far faster than it takes to transmit serial to this EPROM simulator. EEPROM and Flash were developed for this purpose.

The Dataman S4 does. So does the EETools EeRom-8U.

Flashing in-system depends on being able to download to the system, and being able to host the flash code somewhere else. Bootstrapping the circuit to that point needs ... something. Cool

To download faster than the memSIM2 you need Ethernet, and it will give 10Mbps TFTP a run for its money on raw throughput, even without flash overheads (it runs its internal UART at 460kbps).

Mask-ROM'ed bootloaders, USB DFU and internal flash probably killed the market.

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