AT91SAM7X128 Atmel, AT91SAM7X128 Datasheet - Page 288

• Manufacturer Part Number: AT91SAM7X128
• Description: MCU 32-Bit 91S ARM7TDMI RISC 128KB Flash 1.8V/3.3V 100-Pin LQFP
• Manufacturer: Atmel

Specifications of AT91SAM7X128

• Package: 100LQFP
• Device Core: ARM7TDMI
• Family Name: 91S
• Maximum Speed: 55 MHz
• Ram Size: 32 KB
• Program Memory Size: 128 KB
• Operating Supply Voltage: 1.8|3.3 V
• Data Bus Width: 32 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 62
• Interface Type: CAN/Ethernet/SPI/I2S/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

29.5.6
288
AT91SAM7X512/256/128 Preliminary
Read/Write Flowcharts
The following flowcharts shown in
page
give examples for read and write operations. A polling or interrupt method can be used to check
the status bits. The interrupt method requires that the interrupt enable register (TWI_IER) be
configured first.
Figure 29-13. TWI Write Operation with Single Data Byte without Internal Address
290,
Figure 29-16 on page
(CLDIV, CHDIV, CKDIV) in TWI_CWGR
- Device slave address (DADR)
Set the Master Mode register:
291,
Write ==> bit MREAD = 0
TWI_THR = Data to send
Set the Control register:
Load Transmit register
- Transfer direction bit
Read Status register
Read Status register
Figure
(Needed only once)
TWI_CR = MSEN
Transfer finished
- Master enable
TXCOMP = 1?
Set TWI clock
Figure 29-17 on page 292
TXRDY = 1?
Yes
Yes
BEGIN
29-13,
Figure 29-14 on page
No
No
and
Figure 29-18 on page 293
289,
6120H–ATARM–17-Feb-09
Figure 29-15 on