diff options
-rw-r--r-- | firmware/usbconfig.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/firmware/usbconfig.h b/firmware/usbconfig.h index 65864df..7ca31c5 100644 --- a/firmware/usbconfig.h +++ b/firmware/usbconfig.h @@ -184,7 +184,18 @@ return;\ /* define this macro to 1 if you want the function usbMeasureFrameLength() * compiled in. This function can be used to calibrate the AVR's RC oscillator. */ -#define USB_USE_FAST_CRC 0 + + +#if USB_CFG_CLOCK_KHZ<16000 + #define USB_USE_FAST_CRC 1 +#else + #define USB_USE_FAST_CRC 0 +#endif + +/* If the CPU clock is below 16Mhz you have to use the faster CRC routines. + * otherwise time outs may occur on USB3.0 ports. This adds 20 bytes. + */ + /* The assembler module has two implementations for the CRC algorithm. One is * faster, the other is smaller. This CRC routine is only used for transmitted * messages where timing is not critical. The faster routine needs 31 cycles |