Re: USB-serial adapter suggestions needed

> On Dec 28, 2023, at 18:46, bob prohaska <fbsd@www.zefox.net> wrote:
> 
> On Thu, Dec 28, 2023 at 12:38:58PM -0800, Mark Millard wrote:
>> On Dec 28, 2023, at 11:24, bob prohaska <fbsd@www.zefox.net> wrote:
>> 
>>> On Wed, Dec 27, 2023 at 12:27:33PM -0800, Mark Millard wrote:
>>>> 
>>>> Overall I've not been able to understand what the
>>>> (various?) hypothesized stage-by-stage byte flow
>>>> paths are in these notes.
>>>> 
>>> 
>>> Maybe this will help. The path is
>>> 
>>> workstation> Ethernet > terminal server:usb-serial > serial wires> GPIO 8/10
>>> 
>>> I hesitated to use the words "terminal server" because that has implications
>>> (distinct IP address, multiple serial interfaces) that don't exist here.
>>> 
>>> The workstation is a RasPiOS Pi4, the Pi3 host called pelorus is the terminal
>>> server and the GPIO pins are on the Pi3 host named www.zefox.net .
>> 
>> Your prior messages reported text referencing .org, such as:
>> 
>> FreeBSD/arm64 (www.zefox.org) (ttyu1)
>> 
>> and:
>> 
>> No, the garbled login prompt originates from www.zefox.org's
>> serial console.
>> 
>> and:
>> 
>> Understood, it's been hard to articulate 8-( Maybe
>> Workstation > ethernet > pelorus > usb port > gpio 8,10 > console www.zefox.org
>> is a little clearer
>> 
>> So: "www.zefox.net <http://www.zefox.net/>" above is a change of report, if I understand
>> right.
>> 
> 
> It's my typo 8-(
> The host generating console output is the Pi3 named www.zefox.org .
> The host named www.zefox.net isn't involved at all, though it is
> present and I typed its name in error.
> 
>>> The Ethernet connection works well enough for all the other hosts  that I think
>>> we can disregard whether it's wired or WiFi and LAN or WAN or all four.
>> 
>> You have also reported that:
>> 
>> The Pi3 which reported the garbled login prompt
>> uses in config.txt:
>> b@www:/boot/msdos % more config.txt
>> init_uart_clock=3000000
>> enable_uart=1
>> kernel=u-boot.bin
>> kernel7=u-boot.bin
>> dtoverlay=mmc
>> force_mac_address=b8:27:eb:71:46:4f
>> 
>> This is using the mini-uart for the serial console and the
>> full-function UART for bluetooth. It also is not using
>> arm_64bit=1 . (So armv7 support instead of aarch64 support?)
>> 
> 
> You are correct, it's using the mini-uart (which I didn't realize)
> per sysctl.  The machine is running aarch64, the reference to kernel7
> in config.txt is a mistake.  Bluetooth and WiFi aren't used on www.zefox.org.

For RPi3B*’s, booting as aarch64 should have arm_64bit=1 in config.txt , as I understand.

Use of the mini-uart is probably not a good idea for the serial console: dtoverlay=disable-bt should also be listed, like for the other RPi3B* .

In fact, other than the force_mac_address, the general content should be like the one with arm_64bit=1 as far as I can tell. Do you have specific reasons for needing any of the differences?

>> https://elinux.org/RPi_Serial_Connection claims:
>> 
>> QUOTE
>> . . . the less capable mini-UART with no break detection, no framing errors
>> detection, no parity bit, no receive timeout interrupt and no DCD, DSR,
>> DTR or RI signals
>> END QUOTE
>> 
>> This contrasts with:
>> 
>> The Pi3 hosting the usb-serial adapter has in config.txt
>> bob@pelorus:~ % more /boot/efi/config.txt
>> [all]
>> arm_64bit=1
>> dtparam=audio=on,i2c_arm=on,spi=on
>> dtoverlay=mmc
>> dtoverlay=disable-bt
>> device_tree_address=0x4000
>> kernel=u-boot.bin
>> 
>> which has the full-function UART for its serial console
>> and is using arm_64bit=1 .
>> 
>> Why the variation?
>> 
> 
> That machine is the terminal server, pelorus, on the LAN. Its
> internal uart does not participate in the data transmission chain.
> "Hosting the usb-serial converter" was my euphemism for terminal server.
> 
> Please accept my apologies for not proofreading more carefully!
> If there is a better choice of terminology please tell me.
> 
> Thanks for your patience!
> 
> bob prohaska

Note: edited on an iPad. For now, the computers I normally use are not available. My ability to lookup some types of information is greatly limited. I will soon be without internet access for some number of days.