Signaltap problem with emulated blaster


Found problem if signaltap capture memory is 2048 bits or more. (can't do 8x256 capture)

This cause is failing error message "Invalid data received". Under 2048 bit seems to work.

Has anyone tested big signaltaps with emulated blaster or real USB blaster with Vidor.

I have official drivers because I also use terasic USB blaster for other cards.

Arduino 1.8.8
Quartus Prime lite 18.1

USBBlaster (v1.0.0)

Hi Limba,

I have successfully captured over 2K samples by adding "USBBlaster.setOutEpSize(60);" into the USB_Blaster.ino.

void setup() {


It is mentioned in the known issues section:

I think that was only for BSOD case.
I will try that.

-> USBBlaster.setOutEpSize(60);
Didn't do autodetect in programmer. Hangs

-> USBBlaster.setOutEpSize(64);
Works ok and also 2k sample 16kbit capture seems work with original drivers.

16kbit data offload takes 16s but it works. So don't do any big captures.

Did some test with DE0-Nano. 4 signal 32k depth (128kbit). Whole capture was about 1.5s
So if I need to debug something in HW then I use real braster.
Also remember to use testbench and simulate.

Thank you for your reports.

I tested again with different EP size:

-> Without setOutEpSize();

-> setOutEpSize(60);
OK, 4K samples 290Kbits data can be offloaded in an instant.

-> setOutEpSize(64);

Hmm, the appropriate EP size seems to be dependent on an environment as described in the USB_Blaster's readme.

My environment:
Arduino IDE 1.8.8
Quartus Prime lite 18.1
Windows 10 Pro 64bit, Altera USB-Blaster driver: 2014/08/25 Ver.


32 byte endpoint seems to work for me.

256kbit transfer seems to take little under 1s.