Feature #5627
closed
- % Done changed from 0 to 10
1U enclosure, APU, PSU have arrived meanwhile
"The 12V PSU could be shared."
Not sure about that, see other thread. The 12V powering the GPS02 should be floating wrt to PE at the rack side, meaning that APU would need to be floating as well.
On Fri, Aug 12, 2022 at 10:36:30AM +0000, tnt wrote:
"The 12V PSU could be shared."
Not sure about that, see other thread. The 12V powering the GPS02 should be floating wrt to PE at the rack side, meaning that APU would need to be floating as well.
Yes, I also realized that. Luckily the Varia-Systems "DualRack" enclosure actually can mount two completely
separate 12V PSU. We'll use one only for the "isolated" side of your RS422 circuit and the GPS02 (floating
with respect to PE at the rack) and the other one for the APU [and hence indirectly the icE1usb 5V] itself,
referenced to PE.
Just assembled the base 1U "DualRack" enclosure. It now contains 2x PS35 12V PSU (1x APU, 1x for the GPS02), the APU mainboard, 120GB SSD and a fan.
An icE40 is also already present, but not yet mounted/fixed in any way yet.
- Status changed from New to In Progress
This is fully assembled now; APU GPIO control over relay to switch 12V phantom supply is confirmed working.
only missing part now is the icE1 RS422 daughterboard from tnt which hopefully arrives tomorrow. At that point this 1U device can be fully completed. I'll take some picture before closing the lid.
Current picture of the 1U device:
For the icE1usb console we can unfortunately not use any of the APUs UART ports, as they cannot do 1,000,000 bps but only 499200/748800/1497600 (in excess of the usual rates up to 115k2). So this means a USB-UART (like CP2102) must be used for this connection.
crimping parts for the icE1usb internal USB cable should arrive tomorrow (so I can build a 2.54mm to USB-C cable).
Well we could also just change the console baudrate ... this uses a special ice1usb firmware anyway.
On Tue, Sep 06, 2022 at 08:17:47AM +0000, tnt wrote:
Well we could also just change the console baudrate ... this uses a special ice1usb firmware anyway.
I already programmed a CP2102 for 1000000, just need to build a cable with an internal 5pin usb header.
Let's not complicate the gateware/firmware for this one-off installation.
OTOTH, if 921600 or some other multiple-of-115200 would be possible in general without a lot of effort, it
would probably make sense even for the normal icE1usb. This will avoid the need of constantly reprogramming
the CP2102 cables between the 921600 (all the simtrace2 based hardware) and the 1000000 rates (icE1usb).
Final picture [almost] before closing the enclosure.
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