M55800A Atmel Corporation, M55800A Datasheet - Page 21

• Manufacturer Part Number: M55800A
• Manufacturer: Atmel Corporation

Specifications of M55800A

• Flash (kbytes): 0 Kbytes
• Pin Count: 176
• Max. Operating Frequency: 33 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 58
• Ext Interrupts: 58
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 3
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 72
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 8
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.3/5.0
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Chip Select Lines
1354D–ATARM–08/02
The EBI provides up to eight chip select lines:
•
•
By exchanging address lines for chip select lines, the user can optimize the EBI to suit
the external memory requirements: more external devices or larger address range for
each device.
The selection is controlled by the ALE field in EBI_MCR (Memory Control Register). The
following combinations are possible:
Figure 7. Memory Connections for Four External Devices
Note:
EBI
Chip select lines NCS0 - NCS3 are dedicated to the EBI (not multiplexed).
Chip select lines CS4 - CS7 are multiplexed with the top four address lines A23 -
A20.
A20, A21, A22, A23 (configuration by default)
A20, A21, A22, CS4
A20, A21, CS5, CS4
A20, CS6, CS5, CS4
CS7, CS6, CS5, CS4
NCS0 - NCS3
For four external devices, the maximum address space per device is 16M bytes.
D0 - D15
A0 - A23
NWRx
NRD
8 or 16
NCS0
NCS1
AT91X40 Series
NCS2
D0 - D15 or D0 - D7
NCS3
Memory Enable
Output Enable
Write Enable
A0 - A23
Memory Enable
Memory Enable
Memory Enable
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