Hi all,
This has been bugging me for a while, and i'd rather just know as opposed to potentially frying some equipment..
A mate of mine lent me his cache of well looked after Gridseed Blades, to muck around with and test out. All of the units worked, aside from one which has one dead PCB (since removed). After a LOT of messing around, I was able to determine that the MCU/RS232 TTL hardware on this PCB had died and have since removed the chip from the board (this is after making sure it wasnt a case of bad firmware etc).
Can anyone say for sure, that the role of the STM32Fxxx MCU is purely for translating from USB to RS232 TTL? I've read that it has a hand in setting the voltage for the GC3355's.. does it also handle multiplexing for communication to each hashing IC - or are they all wired in a common bus layout (hence the ID selection for each GC3355).
I'm not particularly keen on installing a new MCU to the board, however I would be game enough to solder the 4 or 5 wires required for a MAX232CPE (for a regular PC serial port to TTL convertor) as well as the 3.3/5v required in the same PCB area.
The GC3355 datasheets on github (
https://github.com/gridseed/gc3355-doc/blob/master/GC3355_1Chip_EVB.pdf and
https://github.com/gridseed/gc3355-doc/blob/master/GC3355_8Chip_Sch.pdf) don't seem to rely on an MCU being present - which makes me think that addressing through UART-alone might work.
I'd also previously owned a Zeus Thunder X3 - which literally let you chain each blade like it was on a 'bus', which supports my thinking of this being possible.
Can someone please set me straight on this; only if you know..
james
The voltage is not software adjustable. the STM32 only serves as the USB interface to send the work to the chains of chips, including the frequency setting.
I should still have the firmware somewhere on one of my HDDs.
The design of the blade is based on the 8 chip design that can be found on github, simply 5x copy/paste.
From what I remember, the 5 chains of chips are in parallel, and the 40 chips can't be individually addressed since the chips address only offers 8 possibilities, so each chip 1 from the different chains will get the same part of work, and so on.