08-11-2020, 10:55 AM
(08-08-2020, 06:47 PM)t4_4t Wrote: If the "DE-9 RS-232" you presented means a true "RS-232C port", the signal voltage is +-12V.
If connected carelessly, it may be electrically damaged.
Yes, you are correct—I was confused by several product listings advertising "3.3V to 5V" when that refers to the range of the converter chip's power supply, not to the actual voltage shifting occurring.
Quote:Unless you have a specific reason, I think using a generic "USB-UART" device is the smartest way to go.
If so, it is easy to obtain, and you can buy it for about $2 at Amazon etc. in most countries.
The important point is to make sure that it supports 1.5MBPS.
There are no spare USB ports on the other machine to connect a USB adapter.
It seems like most UART->RS232 chips are some variant of the MAX232 series, so there's not much decision-making to do. Supposedly some of these chips support 1.5Mbps throughput, but it may not be documented at all. I'll probably just end up using 115200bps in U-boot and Linux.
