@rjenkinsgb
That change looks like it fixed the issue...

; Bed Heater
M308 S0 P"bedtemp" Y"thermistor" T100000 B4138 A"Bed Heater"    ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0                              ; create bed heater output on bedheat and map it to sensor 0
;M307 H0 B0 S0.90                                   ; use PID tuning for the bed heater and set PWM limit // CONFIG_OVERRIDE handles this
M140 H0                                            ; map bed to heater 0
M140 S25 R40                                       ; active/standby to 25/40.  turn off bed heater by setting to -273
M143 H0 S120                                       ; set temperature limit for heater 0 to 120C

; Hot End Heater
M308 S1 P"e0temp" Y"thermistor" T100000 B4138 A"Hot End"      ; configure sensor 1 as thermistor on pin e0temp
M950 H1 C"e0heat" T1                               ; create nozzle heater output on e0heat and map it to sensor 1
;M307 H1 B0 S0.90                                   ; CONFIG_OVERRIDE handles this
M143 H1 S280                                       ; set temperature limit for heater 1 to 280C

; Tools
M563 P0 S"DeltaEffector" H1 F0 			   ; define tool 0 with heater 1 and Fan 0
M568 P0 R20 S25 A0                                 ; Set tool 0 Active/Standby=25C/20C/Off
G10 P0 X0 Y0 Z0                                    ; set tool 0 axis offsets

@dc42 No big deal, I've worked with smaller SMD packages before. WizNet W5500, 48LQFP. $4 at DigiKey. Beats having to buy another board, even if the Duet 3 Mini 5 looks really good.

The IC should be here in the next few days. I'll let you know how it goes.

@dc42 it really appeared that it's cycling at about 4Hz steadily, with or without the card in.

I unplugged all cables and actually traced the problem to something on the hot end, plugged into IO_1. Most likely the BL touch or the gyro. Unplugging that brought back the 1Hz blink and my fans powering up.

I should have checked the wiring first. Silly mistake.

@dc42 it really appeared that it's cycling at about 4Hz steadily, with or without the card in.

I unplugged all cables and actually traced the problem to something on the hot end, plugged into IO_1. Most likely the BL touch or the gyro. Unplugging that brought back the 1Hz blink and my fans powering up.

I should have checked the wiring first. Silly mistake.

Ran through the RRF configurator, dumped the whole config package to the included 512MB microSD, formatted as FAT.

SD Contents:
firmware/Duet3Firmware_Mini5plus.uf2
sys/*.g
www/*

When I power on everything, the board doesn't seem to be responding. The panel due is showing black and grey rows of noise. It is running 3.4.1 firmware and was previously working with my Duet 2 Ethernet. The main board never connects to wifi and the LED Lights are as follows:
G,R,R,B - all steady on
red status - rapid blinking, steady 2-3 per sec

I thought maybe the mainboard needed a firmware update, so I tried to flash it by directly connecting a usb to it while unpowered. I couldn't get the board into bootloader mode vi the 2x reset trick. Using several different cables, I was unable to get any ack from my pc that it was connected. No device showed (Duet, BOSSA, unknown).

Any ideas? Is it toast?

Some documentation mentions erasing firmware and reflashing. I couldn't locate the erase jumper. Does this board even have one?

Thanks in advance for the help!

@dc42 - any ideas? or just toast?

Nope. No ethernet lights on the card or the network port.

Network is enabled, configured IP address: 0.0.0.0, actual IP address: 0.0.0.0

So i soldered in a new W5500. Boots up fine, panelDue communicates fine with the board, but ethernet still is non-functional.

m552 s0
Network stopped<LF>ok<LF>
m552 s1
ok
m552
Network is enabled, configured IP address: 192.168.1.50, actual IP address: 192.168.1.50<LF>ok<LF>
m115
FIRMWARE_NAME: RepRapFirmware for Duet 2 Maestro FIRMWARE_VERSION: 3.4.0rc2 ELECTRONICS: Duet Maestro 1.0 FIRMWARE_DATE: 2022-02-22 17:06:07
ok

There is no visible damage to anything on the board. I looked at it under magnification and nothing was burnt, cracked, or popped.

It's been sitting around for 4+ years with very sporadic use. Could just be "old". Maybe the head crash pushed some amps into the Atmel? I'm at a loss at this point.

The IC should be here in the next few days. I'll let you know how it goes.

@dc42 No big deal, I've worked with smaller SMD packages before. WizNet W5500, 48LQFP. $4 at DigiKey. Beats having to buy another board, even if the Duet 3 Mini 5 looks really good.

Think I might be hosed and will need to use DSF with a Pi?

Here's something interesting I discovered while serial debugging....

Anything in ***** is my comment

With mains power...

M115
FIRMWARE_NAME: RepRapFirmware for Duet 2 Maestro FIRMWARE_VERSION: 3.4.0rc2 ELECTRONICS: Duet Maestro 1.0 FIRMWARE_DATE: 2022-02-22 17:06:07
ok
M552
Network is enabled, configured IP address: 192.168.1.50, actual IP address: 192.168.1.50
ok
M552 S0
***** App hung here for a second*****
***** USB dropped and reconnected *****
M552
M552
M552
***** I had to disconnect and reconnect terminal to get any response*****
M552 S1
ok
M552
Network is enabled, configured IP address: 192.168.1.50, actual IP address: 192.168.1.50
ok

when it's powered just by USB...

M115
FIRMWARE_NAME: RepRapFirmware for Duet 2 Maestro FIRMWARE_VERSION: 3.4.0rc2 ELECTRONICS: Duet Maestro 1.0 FIRMWARE_DATE: 2022-02-22 17:06:07
ok
M552
Network is enabled, configured IP address: 192.168.1.50, actual IP address: 192.168.1.50
ok
M552 S0
M552   ***** No response *****
M552
M552 S1
***** terminal disconnects here, but allows reconnection ******
M115
FIRMWARE_NAME: RepRapFirmware for Duet 2 Maestro FIRMWARE_VERSION: 3.4.0rc2 ELECTRONICS: Duet Maestro 1.0 FIRMWARE_DATE: 2022-02-22 17:06:07
ok
M552
Network is enabled, configured IP address: 192.168.1.50, actual IP address: 192.168.1.50
ok