Information

System Configuration
MPC8308 PowerQUICC II Pro Processor Reference Manual, Rev. 1
Freescale Semiconductor 5-41
5.4.5 External Signal Description
Table 5-54 lists the external signals for the RTC module.
5.4.6 RTC Memory Map/Register Definition
The RTC programmable register map occupies 32 bytes of memory-mapped space. Reading undefined
portions of the memory map returns all zeros; writing has no effect.
All RTC registers are 32 bits wide that are located on 32-bit address boundaries and should only be
accessed as 32-bit quantities.
All addresses used in this section are offsets from the RTC base. For more information, see Chapter 3,
“Memory Map.”
Table 5-38 shows the memory map of the RTC.
Table 5-37. RTC External Signals
Signal I/O Description
RTC_PIT_CLOCK I This signal is used as the timebase for the real time clock module.
State Meaning —
Timing 32.768 KHz typical
Requirements —
Reset State Always input
Table 5-38. RTC Register Address Map
Offset Register Access Reset Value
1
1
It refers to the case where software writes to a specific RTC register, RTCCR. For more information, see Section 5.4.8, “RTC
Reset Sequence.”
Section/
Page
Real Time Clock (RTC)—Block Base Address 0x0_0300
0x000 Real time counter control register (RTCNR) R/W 0x0000_0000 5.4.6.1/5-42
0x004 Real time counter load register (RTLDR) R/W 0x0000_0000 5.4.6.2/5-43
0x008 Real time counter prescale register (RTPSR) R/W 0x0000_0000 5.4.6.3/5-43
0x00C Real time counter register (RTCTR) R 0x0000_0000 5.4.6.4/5-44
0x010 Real time counter event register (RTEVR) w1c 0x0000_0000 5.4.6.5/5-44
0x014 Real time counter alarm register (RTALR) R/W 0xFFFF_FFFF 5.4.6.6/5-45
0x018–0x01F Reserved — —