AT90USB647-MU Atmel, AT90USB647-MU Datasheet - Page 38

• Manufacturer Part Number: AT90USB647-MU
• Description: MCU, 8BIT, 64K FLASH, USB, 64QFN
• Manufacturer: Atmel

Specifications of AT90USB647-MU

• Controller Family/series: AT90
• No. Of I/o's: 48
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 16MHz
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 64KB
• Oscillator Type: External, Internal
• Package: 64QFN EP
• Device Core: AVR
• Family Name: AT90
• Maximum Speed: 20 MHz
• Ram Size: 4 KB
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 48
• Interface Type: SPI/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 4
• Lead Free Status / Rohs Status: Details

38
AT90USB64/128
Note:
Assembly Code Example
C Code Example
#define OFFSET 0x4000
void XRAM_example(void)
{
}
; OFFSET is defined to 0x4000 to ensure
; external memory access
; Configure Port C (address high byte) to
; output 0x00 when the pins are released
; for normal Port Pin operation
ldi
out
ldi
out
; release PC7:6
ldi
sts
; write 0xAA to address 0x0001 of external
; memory
ldi
sts
; re-enable PC7:6 for external memory
ldi
sts
; store 0x55 to address (OFFSET + 1) of
; external memory
ldi
sts
unsigned char *p = (unsigned char *) (OFFSET + 1);
DDRC = 0xFF;
PORTC = 0x00;
XMCRB = (1<<XMM1);
*p = 0xaa;
XMCRB = 0x00;
*p = 0x55;
1. See “About Code Examples” on page 9.
r16, 0xFF
DDRC, r16
r16, 0x00
PORTC, r16
r16, (1<<XMM1)
XMCRB, r16
r16, 0xaa
0x0001+OFFSET, r16
r16, (0<<XMM1)
XMCRB, r16
r16, 0x55
0x0001+OFFSET, r16
(1)
(1)
7593K–AVR–11/09