Yep here is the sales thread. Postage prices have all gone up as of Monday - 8% inflation busting rise, thanks RM - so £2.25 UK 1st class now.
27C400/27C800 EPROM emulator
Re: 27C400/27C800 EPROM emulator
- rubber_jonnie
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Re: 27C400/27C800 EPROM emulator
@cmorley Thank you.cmorley wrote: ↑Fri Mar 27, 2020 10:02 amYep here is the sales thread. Postage prices have all gone up as of Monday - 8% inflation busting rise, thanks RM - so £2.25 UK 1st class now.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: 27C400/27C800 EPROM emulator
OK... I found some enthusiasm and finished the "no reset wire" firmware.
v0.7 firmware dropbox link
You will need to update the microcontroller and the CPLD firmware.
After upgrading go in to the options and set them as you wish. Don't forget you can use the PRESET wizard to set the module up quickly. Also don't forget to COMMIT the options to FLASH.
ROM switch timings are a bit quicker now.
<1s - ignore
>1s - switch to NEXT ROM
>3s - swithc to ROM zero (optionally quick tap reset n times to go to ROM n)
>5s - no ROM switch
You can connect a (power) LED to the pad next to PIN 1. It is open drain so you connect the other end of the LED to 5v - use a series resistor so the microcontroller pin isn't current limiting.
The ROM switch without using a RESET wire works by monitoring A0. If it sees no change on A0 for a while (>30ms) it assumes the machine is in RESET. I have tested this on an Amiga A500. It might work on other machines (very probably most other 680x0 machines) depends on the CPU behaviour when in reset.
Chris
v0.7 firmware dropbox link
You will need to update the microcontroller and the CPLD firmware.
After upgrading go in to the options and set them as you wish. Don't forget you can use the PRESET wizard to set the module up quickly. Also don't forget to COMMIT the options to FLASH.
ROM switch timings are a bit quicker now.
<1s - ignore
>1s - switch to NEXT ROM
>3s - swithc to ROM zero (optionally quick tap reset n times to go to ROM n)
>5s - no ROM switch
You can connect a (power) LED to the pad next to PIN 1. It is open drain so you connect the other end of the LED to 5v - use a series resistor so the microcontroller pin isn't current limiting.
The ROM switch without using a RESET wire works by monitoring A0. If it sees no change on A0 for a while (>30ms) it assumes the machine is in RESET. I have tested this on an Amiga A500. It might work on other machines (very probably most other 680x0 machines) depends on the CPU behaviour when in reset.
Chris
Re: 27C400/27C800 EPROM emulator
Firmware like buses!
v0.8 firmware dropbox link
Improved debounce on ROM switch signal.
I found the wireless ROM switch was unreliable on a different Amiga so I improved the debounce a little.
v0.8 firmware dropbox link
Improved debounce on ROM switch signal.
I found the wireless ROM switch was unreliable on a different Amiga so I improved the debounce a little.
Re: 27C400/27C800 EPROM emulator
v0.8 Firmware works with wireless ROM switching on the 6502 based Acorn Master too
No flylead/clip required.
No flylead/clip required.
Re: 27C400/27C800 EPROM emulator
No complaints about v0.8 firmware problems... does that mean it works for people or no one was brave enough to try it yet?
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Re: 27C400/27C800 EPROM emulator
I should update and try!
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
Re: 27C400/27C800 EPROM emulator
I've tested the v0.8 firmware in my Amiga A1200 & A600 now.
Works in both but the reset seems a bit delayed (is it debounced?) on an A1200 so you should wait for the LED to go dim then count the seconds to switch ROM.
On A1200 & A600 the board pins are very close to the back metal of the keyboard. Shorter pins (& cropped) and insulation is a must - expecially on the A1200 where the keyboard can flex. Otherwise the keyboard will touch pins 1-20 (there is no Vcc on that side but still don't short the address bus!)
Works in both but the reset seems a bit delayed (is it debounced?) on an A1200 so you should wait for the LED to go dim then count the seconds to switch ROM.
On A1200 & A600 the board pins are very close to the back metal of the keyboard. Shorter pins (& cropped) and insulation is a must - expecially on the A1200 where the keyboard can flex. Otherwise the keyboard will touch pins 1-20 (there is no Vcc on that side but still don't short the address bus!)
- simon.wilkie
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Re: 27C400/27C800 EPROM emulator
Just checked this on my setup and the pins are NOT close to the rear of the keyboard on a 1200 as long as you have either the hard drive caddy installed or the floppy securing bracket as the keyboard rests on these far above the EPROMS.cmorley wrote: ↑Tue May 19, 2020 12:58 pm I've tested the v0.8 firmware in my Amiga A1200 & A600 now.
Works in both but the reset seems a bit delayed (is it debounced?) on an A1200 so you should wait for the LED to go dim then count the seconds to switch ROM.
On A1200 & A600 the board pins are very close to the back metal of the keyboard. Shorter pins (& cropped) and insulation is a must - expecially on the A1200 where the keyboard can flex. Otherwise the keyboard will touch pins 1-20 (there is no Vcc on that side but still don't short the address bus!)
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Re: 27C400/27C800 EPROM emulator
Hi,
Can I ask a silly question? So i have flashed a ROM with EmuTOS in 27C200 mode, 256KB rom, slot 0.Works.
I then flashed slot 1 with DiagROMST.
I then selected slot 1 using "w" in the boot menu. But it always boots EmuTOS. I dont want any external pins to select the rom. just the setting in the menu. Does this work? It always boots EmuTOS even though the browser shows DiagROM code in slot 1.
Sorry if this is obvious. I have the latest firmware updates.
This is using @exxos's new decoder and @EzdineG's A1000 rom switcher for crossing the streams fun.
Can I ask a silly question? So i have flashed a ROM with EmuTOS in 27C200 mode, 256KB rom, slot 0.Works.
I then flashed slot 1 with DiagROMST.
I then selected slot 1 using "w" in the boot menu. But it always boots EmuTOS. I dont want any external pins to select the rom. just the setting in the menu. Does this work? It always boots EmuTOS even though the browser shows DiagROM code in slot 1.
Sorry if this is obvious. I have the latest firmware updates.
This is using @exxos's new decoder and @EzdineG's A1000 rom switcher for crossing the streams fun.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."