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Author Topic: FPGA Replay Board  (Read 826112 times)

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Offline freqmax

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Re: FPGA Replay Board
« Reply #164 on: December 19, 2011, 08:22:15 PM »
If you do a follow up will it be the same layout or is slight component optimization a possibility?
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #165 on: December 19, 2011, 11:21:06 PM »
I think onboard Ethernet that the ARM CPU can handle would be really useful. And I suspect the first batch will produce some feedback that can be used to improve the next version.
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #166 on: December 20, 2011, 03:48:44 PM »
From the mechanical side, I hope there's room for standoffs on the baseboard such that the daugherboard has something to stand on.
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #167 on: December 20, 2011, 11:44:06 PM »
The pinout is below, and the keyboard protocol is likely "standard Amiga" ..
The mouse is another problem however. Special pinout and special protocoll. But I think it can be solved with an adapter and new HDL-code.

Keyboard (5 pin mini-DIN):

amiga-hardware.com - Commodore: CDTV Keyboard
cdtv.org.uk: Commodore CDTV Expansion Ports Explained
l8r.net: Amiga Keyboard Pinouts

Pin   Signal
 1    GND    
 2    KBDATA
 3    KBCLOCK
 4    Vcc
 5    KBSE
 6

Mouse (4 pin mini-DIN):

cdtv.org.uk: Commodore CDTV Expansion Ports Explained from link at abime.net
Pin Signal
 1 GND
 2 GND
 3 PRDT (Mouse Data?)
 4 +5V

(pain in the ass to find out)
« Last Edit: December 21, 2011, 12:38:36 AM by freqmax »
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #168 on: December 21, 2011, 03:04:06 PM »
@mikej, How tight is code space?

Selection can be done by pressing some Amiga keyboard specific key.

A note thoe, all Amiga keyboards seems to use their own unique pinout. So a heap of adapters will be needed. Otoh, one use a Amiga->PS/2 keycode translator when at it anyway ;)
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #169 on: December 21, 2011, 05:53:51 PM »
Bit banging in a CPU infer the risk of unreliable operation.
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #170 on: December 21, 2011, 07:12:16 PM »
Interrupt congestion and timing margins are your suprise attacks ;)
Especially if you have to deal with other time critical events simultainously.

Another possibility is a microcontroller like Atmel-AVR that translate between PS/2 and "Amiga". The CDTV mouse is in particular an protocoll anomality.
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #171 on: December 28, 2011, 01:04:05 AM »
@Darrin, actually the MC68SEC000 cpu used is not fully compatible. It misses E-clock, and MOVE sr, is privileged. But I guess it has little practical impact.
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #172 on: December 28, 2011, 06:33:15 AM »
How does one split the ROM?, or rather extract and insert object (driver) files from the binary ROM blob?
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #173 on: December 28, 2011, 08:11:30 PM »
Something for the silk screen
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #174 on: December 29, 2011, 03:08:02 AM »
tl;dr. ?
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #175 on: December 30, 2011, 12:31:49 AM »
Time for an DVI -> SCART cable? ;)

(less connectors that degrade the signal)
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #176 on: December 30, 2011, 06:13:29 PM »
I think Dennis that showed it actually could be done despite all nay-sayers, is one to interview.
« Last Edit: December 30, 2011, 08:47:42 PM by freqmax »
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #177 on: January 02, 2012, 05:30:42 PM »
Just a thought regarding the FPGA Arcade CPU (ARM). Will it be possible to reprogram it without additional tools lika physical JTAG programmer? ie special file on the SD-card?
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #178 on: January 02, 2012, 09:28:50 PM »
Quote from: Darrin;674016
Do you mean for reflashing the firmware (like on the bare Minimig where you have to use the serial port)?  Yes, you can simply reflash by putting a file on the SD card and then accessing the OSM "Firmware/update" option.


Yeah the code that controls the ARM-CPU, that controls the FPGA.. ;)

Guess the catch is that you can brick the ARM, so that one need hardcore tools anyway to rectify such situation. The intent is ofcourse to be able test new code ;)
 

Offline freqmax

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Re: FPGA Replay Board
« Reply #179 from previous page: January 03, 2012, 03:39:09 AM »
And it's actually possible to stuff the HDL code for existing implementations of 68k Mac, Speccy, BBC, etc into your own synthesizer software and use the resulting bitfile (core). :p ;)