Philips CD-I - Page 54

1.3.2 System/video RAM.
1 MB RAM is organized in 2 separate banks, each of 512
KB. The RAM is shared by the MPU and the video
controller via access controllers called VSCs. The
program-, video-, and audio-related data share the same
RAM area.
- Total Capacity
- Access time
- Address
bank 1
bank 2
1 Mbyte
Max. 100 nsec
000000 - 07FFFF
080000 -
OFFFFF
1.3.3 Non-volatile RAM (NV-RAM).
The MMC module has an 8 Kbyte Non Volatile-RAM to
store:
o CD-RTOS information like the CSD table
o Intermediate application related data.
- Address
- Access
- Capacity
- Access time
310000 - 31FFFF
byte access only(even address)
8 Kbyte
Max. 150 nsec.
1.3.4 Clock/calendar.
The MMC has a clock-calendar function with the
following characteristics:
o Accuracy of 1 second.
o Stability better than 1 minute per month.
o Counts seconds, minutes, hours, days, months,
and years.
o Handles leap years.
- Address
lFFCOO - 1FFC3F
- Access
byte access only (even address)
3-14
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