ROM Emulation
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Charles released his 16 bit rom emulator doc also...
does it mean I can change the rom content while playing, from my PC ?
does it mean I can change the rom content while playing, from my PC ?
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Yup, he used a dual port SRAM, the code could overwritten on the fly, while the CPU waits, like running some code from MD ram, then jump back to the new code.KanedaFr wrote:Charles released his 16 bit rom emulator doc also...
does it mean I can change the rom content while playing, from my PC ?
I've finally received one of these It took ~6 weeks to come because of problems with customs but it's finally here.
Funny but when I try that my megadrive seems to power on (power switch off, but I can hear the usual static from headphone output) and sometimes I even start getting blank display output! It doesn't seem to run the game though (or it crashes), and when I start the actual flash programming process megadrive starts outputting funny "bleep" noises through it's headphone output. Don't have much idea what's going on, maybe it manages to write to PSG or something.HardWareMan wrote:Yes. It can be programmed when inserted in MD. But I don't sure, how it will be work, when MD power is on. Strongly recommended pull out this FLASH cart when programming.Jorge Nuno wrote:Is the cart reprogamable with the MD on?
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What is going on is that your MD is partially being powered through USB of your PC and its not healthy to the USB port nor the MD. "Pull the cart out please", that is what your MD is trying to say
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
Hmm... then card inserted into megadrive port, "power" lamels on card and power pins in MD connects, and if megadrive does not have power separation by On/Off switch, USB port targetly suplay your megadrive, it means that power ON! Do not programm card in this mode, you can crash device or MD if power separation not present!notaz wrote:I've finally received one of these It took ~6 weeks to come because of problems with customs but it's finally here.
Funny but when I try that my megadrive seems to power on (power switch off, but I can hear the usual static from headphone output) and sometimes I even start getting blank display output! It doesn't seem to run the game though (or it crashes), and when I start the actual flash programming process megadrive starts outputting funny "bleep" noises through it's headphone output. Don't have much idea what's going on, maybe it manages to write to PSG or something.HardWareMan wrote:Yes. It can be programmed when inserted in MD. But I don't sure, how it will be work, when MD power is on. Strongly recommended pull out this FLASH cart when programming.Jorge Nuno wrote:Is the cart reprogamable with the MD on?
TOTALY RIGHT!!!TmEE co.(TM) wrote:What is going on is that your MD is partially being powered through USB of your PC and its not healthy to the USB port nor the MD. "Pull the cart out please", that is what your MD is trying to say
Hire youtube videostinctu wrote:@HardWareMan / Masyanya ->
Do you still have USB carts for MD for sale???
I am from EU.
I want to buy 2x USB Flash Carts.
CAN YOU MAKE YOUTUBE VIDEO???
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Or when you will not sale them so please opensource
USB flashcarts for community...
1. Illustrate save games in 16MX+US mode
2. Illustrate how fast it's writes (Vista, but driver hormaly works in XP, 95, 98, NT, 2000, 2003 Server)
2.a. First stage - ERASE.
2.b. Second stage - Flashing.
3. Illustrate 32MX+UF compatibility mode, saves in rom size>2mb (Story of thor Russian, from http://www.shedevr.org.ru/, RUS translation site.)
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I wish my cart would write that fast...
Is that a real Japanese or Asian MD2 there (I highly doublt pirates like to include the TMSS screen aswell) ?
and your laptop seemed a bit weak for Vista
Is that a real Japanese or Asian MD2 there (I highly doublt pirates like to include the TMSS screen aswell) ?
and your laptop seemed a bit weak for Vista
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
Naturally faster, and thats with that ? ...use SRAM, - but I'm FLASH, it must be erased before write... and others...TmEE co.(TM) wrote:I wish my cart would write that fast...
Is that a real Japanese or Asian MD2 there (I highly doublt pirates like to include the TMSS screen aswell) ?
and your laptop seemed a bit weak for Vista
Write in SRAM 64 bytes (use sram like CY62256-70PC):
1. Set Address
2. Set Data
3. Write Enable Pulse
4. Wait "Write in 70ns"
5. Repeat 1.-4. 64 times.
Write in FLASH 64 bytes (use flash like S29AL016-TFI20 (70ns speed grade)):
0. [Remark] Write in flash valid only if it erased previously
Stage A, - Unlock Bypass
1. Set Address 0x555
2. Set Data 0xAA
3. Write Enable Pulse
4. Set Address 0x2AA
5. Set Data 0x55
6. Write Enable Pulse
7. Set Address 0x555
8. Set Data 0x20
9. Write Enable Pulse
Stage B, - Programm Word
10. Set Data 0xA0
11. Write Enable Pulse
12. Set Data Address
13. Set Data
14. Write Enable Pulse
15. Wait "Write in 5us-150us" match more than 70ns
16. Repeat 10.-15. 32 times.
Of course write in SRAM more fast.
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slowness on my side is because of my stupid LPT programmer device with no smart hardware...
Setting address is :
write data (LSB)
strobe low
strobe high
write data (middle)
strobe low
strobe high
write data (MSB)
strobe low
strobe high
and the flash chips I use have no Unlock Bypass command
and that has to be done many times when writing a flash.... LPT port can handle only about ~1000000 operations per second and I'm totally maxing it, so I get about 4KBytes/second writing speed... reading goes fast like writing SRAM at least
a MCU based device would be much faster but I'm too poor to afford any as of now
Setting address is :
write data (LSB)
strobe low
strobe high
write data (middle)
strobe low
strobe high
write data (MSB)
strobe low
strobe high
and the flash chips I use have no Unlock Bypass command
and that has to be done many times when writing a flash.... LPT port can handle only about ~1000000 operations per second and I'm totally maxing it, so I get about 4KBytes/second writing speed... reading goes fast like writing SRAM at least
a MCU based device would be much faster but I'm too poor to afford any as of now
Mida sa loed ? Nagunii aru ei saa
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen
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So, you using no JEDEC compliant FLASH? Wich one?TmEE co.(TM) wrote:and the flash chips I use have no Unlock Bypass command
Using MCU in device allows to reduce data traffic and optimize data flow. Even on LPT port. Think about it.TmEE co.(TM) wrote:a MCU based device would be much faster but I'm too poor to afford any as of now