Hi there,
So , just a hunch but t looks like the model is still in flash, but it’s not automatically loaded into RAM for inference just by powering up or resetting via UART. This would explain why the MODEL? command returns size: 0, even though it works via SenseCraft.
A few things to try:
- Send a Model Load command manually after reset — something like:
AT+MODELLOAD=1\r
or:
AT+INFERENCE=1\r
(This is a guess—the real command depends on the firmware version and AT command set supported. Seeed hasn’t published a complete AT reference doc publicly, which is a pain.)
(Exact syntax depends on the SSCMA_Micro firmware — Seeed’s docs don’t include the full AT command set, so check firmware release notes or sniff the connection.)
2. SenseCraft probably auto-loads the model over USB — you’re bypassing this when using UART directly. That’s why it works in SenseCraft but not with raw serial commands.
3. If you’re still seeing size: 0, try:
- Power-cycling the device completely
- Then issue your AT+MODEL? again
- Followed by a model load command
- As of version
2025.01.02, the firmware shouldn’t require I2C or USB for model activation — but keep an eye on any hidden dependencies if using advanced features.
Let us know if trying MODELLOAD or similar gets you past the 0-byte issue!
SenseCraft likely sends a “MODEL LOAD” command silently when it connects, which isn’t happening when just using UART manually.
my guess,
HTH
GL 
PJ 
I’ll ask Al see what I get and report back. try the above 
this protocol document proves that YOU must manually run AT+INVOKE=1 over UART to load the model after boot/reset. Without this step, the module won’t load the model into RAM, and AT+MODEL? will show size 0.
So this isn’t a bug — it’s just a required initialization step the SSCMA-Micro firmware expects unless you’re using the Arduino wrapper (which calls it internally).