M42800A Atmel Corporation, M42800A Datasheet - Page 28

• Manufacturer Part Number: M42800A
• Manufacturer: Atmel Corporation

Specifications of M42800A

• Flash (kbytes): 0 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 33 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 54
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Resistive Touch Screen: No
• 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

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AT91M42800A
Figure 11-6. Memory Connection for 2 x 8-bit Data Buses
Byte Select Access is used to connect 16-bit devices in a memory page.
Figure 11-7 shows how to connect a 16-bit device with byte and half-word access (e.g., 16-bit
SRAM) on NCS2.
Figure 11-7. Connection for a 16-bit Data Bus with Byte and Half-word Access
Figure 11-8 shows how to connect a 16-bit device without byte access (e.g., Flash) on NCS2.
• The signal A0/NLB is used as NLB and enables the lower byte for both read and write
• The signal NWR1/NUB is used as NUB and enables the upper byte for both read and write
• The signal NWR0/NWE is used as NWE and enables writing for byte or half-word.
• The signal NRD/NOE is used as NOE and enables reading for byte or half-word.
operations.
operations.
EBI
EBI
D8 - D15
A1 - A19
D8 - D15
A1 - A19
D0 - D7
D0 - D7
NWR1
NWR0
NCS2
NCS2
NRD
NWE
NOE
NUB
NLB
A0
D0 - D7
A0 - A18
Write Enable
Read Enable
Memory Enable
D8 - D15
A0 - A18
Write Enable
Read Enable
Memory Enable
D0 - D7
D8 - D15
A0 - A18
Low Byte Enable
High Byte Enable
Write Enable
Output Enable
Memory Enable
1779D–ATARM–14-Apr-06