DRAM Controller
Am186™CC/CH/CU Microcontrollers User’s Manual
6-7
6.5.8
Comparison to Other Devices
The DRAM controller is similar to the Am186ED DRAM controller, with these primary
enhancements: 50 MHz, extended refresh interval times, and faster DRAMs. The
Am186CC/CH/CU microcontrollers support 25-ns to 70-ns EDO DRAM only. It does not
support Fast Page mode DRAM.
6.6
INITIALIZATION
On both an external and internal reset, the following occurs:
■
The value of the CDRAM register becomes 0000h, setting the DRAM refresh period to 0.
■
The value of the EDRAM register becomes 0000h, clearing and disabling the refresh
counter.
■
The UDEN bit of the UMCS register and the LDEN bit of the LMCS register both become
0, disabling UCS and LCS DRAM. See Chapter 5, “Chip Selects.”.
■
The CAS and RAS multiplexed pins default to their alternate functions as shown in
Table 6-1 on page 6-2.
■
UCS is the inverse of the state of the UCSX8 that was latched on exiting external reset.
If UCSX8 is 0, UCS is 8 bits wide; if UCSX8 is 1, UCS is 16 bits wide. In either case,
UCS defaults to non-DRAM.
Содержание Am186 CC
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Страница 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Страница 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Страница 39: ...Architectural Overview Am186 CC CH CU Microcontrollers User s Manual 1 15 Figure 1 6 32 Channel Linecard CH CC...
Страница 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Страница 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Страница 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Страница 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Страница 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...