Samsung S5PC100 User Manual page 707

CCAN S5PC100 USER'S MANUAL (REV1.0)
A read access to the C_CAN module with APB2 interface must be performed as "double read". With the first read,
the requested data is written into the internal register (SYNC_PRDATA) clocked by CAN_CLK. With the second
read the data output register PRDATA takes over the value of SYNC_PRDATA (see Figure 8.5-7).
The two consecutive read accesses must have a minimum distance of nine PCLK periods (when frequency
(PCLK) = 4 x frequency (CAN_CLK)).
Figure 8.5-7 APB2 Read Timing
8. 5-10