S3C2440A RISC MICROPROCESSOR CLOCK & POWER MANAGEMENT
7-21
PLL CONTROL REGISTER (MPLLCON & UPLLCON) Register Address R/W Description Reset Value
MPLLCON 0x4C000004 R/W MPLL configuration register 0x00096030
UPLLCON 0x4C000008 R/W UPLL configuration register 0x0004d030
PLLCON Bit Description Initial State
MDIV [19:12] Main divider control 0x96 / 0x4d
PDIV [9:4] Pre-divider control 0x03 / 0x03
SDIV [1:0] Post divider control 0x0 / 0x0
NOTE
When you set MPLL&UPLL values, you have to set the UPLL value first and then the MPLL value. (Needs intervals
approximately 7 NOP)
PLL VALUE SELECTION TABLE
It is not easy to find a proper PLL value. So, we recommend referring to the following PLL value recommendation
table.
Input Frequency Output Frequency MDIV PDIV SDIV
12.0000MHz 48.00 MHz (Note) 56(0X38) 2 2
12.0000MHz 96.00 MHz (Note) 56(0x38) 2 1
12.0000MHz 271.50 MHz 173(0xad) 2 2
12.0000MHz 304.00 MHz 68(0x44) 1 1
12.0000MHz 405.00 MHz 127(0x7f) 2 1
12.0000MHz 532.00 MHz 125(0x7d) 1 1
16.9344MHz 47.98 MHz (Note) 60(0x3c) 4 2
16.9344MHz 95.96 MHz (Note) 60(0x3c) 4 1
16.9344MHz 266.72 MHZ 118(0x76) 2 2
16.9344MHz 296.35 MHZ 97(0x61) 1 2
16.9344MHz 399.65 MHz 110(0x6e) 3 1
16.9344MHz 530.61 MHz 86(0x56) 1 1
16.9344MHz 533.43 MHz 118(0x76) 1 1
NOTE
The 48.00MHz and 96MHz output is used for UPLLCON register.