MSX HDMI mutlimedia card | MSX Resource Center (Страница 6/57)

Champion (512)

04-02-2014, 11:46

MicroTech wrote:

Hi maxis,
first of all congratulation for your excellent work, I'm really interested in procyon.
I have a couple of questions about reconfiguration option 1:
I imagine that DFU means Device Firmware Upgrade.
If I understand correctly, it should be possible, when a procyon is inserted in an MSX slot, to use MSX as host to load fpga contents "on the fly".
During configuration, all fpga pins should be in a sort of high impendance state and should not interfere with other MSX-bus operations.
Hence Procyon should feature an fpga reconfiguration device/mechanism selectable by MSX slot signals (memory or I/O mapped) and should be possible to install (theorically) a procyon board in every slot.
Is this scenario correct?

Procyon natively uses the slot select mechanism to access to it's memory mapped configurator, which is a part of the FPGA design.
During the DFU you don't actually update the FPGA content, but its SPI FLASH via FPGA, which remains configured. At the end of the config the FPGA can be rebooted, re-reading its content from SPI FLASH.
You can individually configure as many Procyon cards as MSX slots you have.

The only potential problem with this DFU mechanism is the power loss in the middle of FLASH reprogramming. Then DFU is possibly doomed since the FLASH is corrupted. The possible solution is
1. External SPI FLASH configuration daughter board
2. Xilinx or any SPI direct programming cable

By maxis

Champion (512)

04-02-2014, 13:43

MicroTech wrote:

first of all congratulation for your excellent work, I'm really interested in procyon.

Thank you, MicroTech for your words and your interest. Did I answer your question?

By MicroTech

Champion (388)

04-02-2014, 16:56

Yes, you did
That's a pity there is this possibility to "brick" procyon.
Maybe a simple joystick <-> spi adapter can be used to load an "emergency" firmware containing only the necessary "hardware" to make fpga still loadable with usual DFU tool.

By MicroTech

Champion (388)

04-02-2014, 17:01

Btw I've another question:

maxis wrote:

At the end of the config the FPGA can be rebooted, re-reading its content from SPI FLASH.

do you need to power off the whole MSX to reboot FPGA?
or DFU mechanism can reset only FPGA via software?

By maxis

Champion (512)

04-02-2014, 18:20

MicroTech wrote:

Yes, you did
That's a pity there is this possibility to "brick" procyon.
Maybe a simple joystick <-> spi adapter can be used to load an "emergency" firmware containing only the necessary "hardware" to make fpga still loadable with usual DFU tool.

Brilliant and elegant idea! Especially since joystick port is the most tested and well supported on ALL the machines. So, this mode can be used to load the "emergency" design into FLASH as you write above. This design could have the MSX slot interface and the SPI FLASH bridge only. So, with joystick connector to 14 pin header cable (on Procyon) the card can't be rendered useless. Excellent suggestion! So, no XILINX cable or PC is needed for the "rescue" DFU.

By maxis

Champion (512)

04-02-2014, 18:18

MicroTech wrote:

Btw I've another question:

maxis wrote:

At the end of the config the FPGA can be rebooted, re-reading its content from SPI FLASH.

do you need to power off the whole MSX to reboot FPGA?
or DFU mechanism can reset only FPGA via software?

Currently the POWER OFF / MSX HW RESET options are only supported. In the improved version for beta-testing I'm going to add a monostable multivibrator for FPGA self-resetting via SW.

By MicroTech

Champion (388)

05-02-2014, 13:17

maxis wrote:

Brilliant and elegant idea!

maxis wrote:

Especially since joystick port is the most tested and well supported on ALL the machines.

Fully agree.
Some years ago I was (and still I'm) an ardent supporter of Acrobat232, a TTL <-> RS232 level adapter designed to work with MSX joystick port: simple to build and drive, economic and usable on any MSX machine.

Let me know if I can be of any help/support in the development of the spi-rescue-tool, it would be an honour for me

By Denus

Expert (120)

25-03-2014, 00:03

I can't wait to see the final product!
Some CNC machine owners should already be working on an elegant case for this PCB...

By o.geerdink

Hero (588)

25-03-2014, 15:04

Count me in for one.

By maxis

Champion (512)

25-03-2014, 18:35

Denus wrote:

I can't wait to see the final product!
Some CNC machine owners should already be working on an elegant case for this PCB...

Hello, Denus,

A nice box is always important. Unfortunately none of my cards ever had one... But now 3D printing changes the game.

BTW, recently I saw on EBAY large ABS plastic box for a cartridge, but can't find it anymore...