uhf-rfid on Core2 sometimes generates `ValueError: buffer too small`

[kmpm]

• UiFlow 2.4.3
• Device: Core2
• UHF-RFID unit connected on Port A.
• MicroPython v1.27.0-dirty on 2026-03-19; M5STACK Core2 with ESP32(SPIRAM)

When I added verbose=True to the setup line uhfrfid_0 = UHFRFIDUnit(2, port=(33, 32), verbose=True) I got some more output that might be helpful. I also annotated the output for clarification.

I made a forum post about the same issue https://forum.m5stack.com/topic/8156/valueerror-buffer-to-small-when-using-uhf-rfid-with-core2

      _  __ _               
 _   _(_)/ _| | _____      __
| | | | | |_| |/ _ \ \ /\ / /
| |_| | |  _| | (_) \ V  V / 
 \__,_|_|_| |_|\___/ \_/\_/  V2.4.3

[INFO] Syncing resources...
[INFO] Network connected!

##### Initializing 
Frame to send: bb 00 07 00 01 03 0b 7e
Recv buffer: bb 01 07 00 01 00 09 7e
Frame to send: bb 00 b6 00 02 0a 28 ea 7e
Recv buffer: bb 01 b6 00 01 00 b8 7e

##### Reading a tag 1
Frame to send: bb 00 22 00 00 22 7e
Recv buffer: bb 02 22 00 11 cf 30 00 e2 80 69 95 00 00 50 09 f1 28 69 92 62 0a 6d 7e
RSSI: 207, PC: 12288, EPC: b'\xe2\x80i\x95\x00\x00P\t\xf1(i\x92', CRC: 25098

##### Reading tag 2
Frame to send: bb 00 22 00 00 22 7e
Recv buffer: bb 02 22 00 11 ca 34 00 30 0e d8 9f 33 50 01 5a 1e 3d f5 06 06 90 b2 7e
RSSI: 202, PC: 13312, EPC: b'0\x0e\xd8\x9f3P\x01Z\x1e=\xf5\x06', CRC: 1680

##### Reading tag 3
Frame to send: bb 00 22 00 00 22 7e
Recv buffer: bb 02 22 00 11 c5 34 00 30 02 a7 dd c7 7e
Traceback (most recent call last):
  File "m5ui/port.py", line 46, in task_handler
  File "main.py", line 33, in button0_event_handler
  File "main.py", line 28, in button0_short_clicked_event
  File "main.py", line 18, in inventory1
  File "unit/uhf_rfid.py", line 19, in inventory
  File "driver/jrd4035/__init__.py", line 72, in inventory
  File "driver/jrd4035/__init__.py", line 445, in command
  File "driver/jrd4035/__init__.py", line 490, in _receive
ValueError: buffer too small

code.py