thodg/cgminer

diff --git a/libbitfury.c b/libbitfury.c
index 80d5ae5..37861f0 100644
--- a/libbitfury.c
+++ b/libbitfury.c
@@ -163,8 +163,10 @@ void spi_config_reg(struct bitfury_info *info, int cfgreg, int ena)
 
 void spi_set_freq(struct bitfury_info *info)
 {
-	unsigned char osc6[8] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F, 0x00, 0x00 };
+	uint64_t freq;
+	const uint8_t *osc6 = (unsigned char *)&freq;
 
+	freq = (1ULL << info->osc6_bits) - 1ULL;
 	spi_add_data(info, 0x6000, osc6, 8); /* Program internal on-die slow oscillator frequency */
 }