SAM7S16 Atmel Corporation, SAM7S16 Datasheet - Page 627

• Manufacturer Part Number: SAM7S16
• Manufacturer: Atmel Corporation

Specifications of SAM7S16

• Flash (kbytes): 16 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 55 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 21
• Ext Interrupts: 21
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

40.7.4.3
40.7.5
40.7.5.1
40.7.5.2
6175L–ATARM–28-Jul-11
Power Management Controller (PMC)
PIO: Drive Low NRST, PA0-PA16 and PA21-PA31
PMC: Slow Clock Selected in PMC and a Transition Occurs on PA1
PMC: Programming CSS in PMC_MCKR Register
It is recommended to use an external pull-up if needed.
When NRST or PA0-PA16 and or PA21-PA31 are set as digital inputs with pull-up enabled, driv-
ing the I/O with an output impedance higher than 500 ohms may not drive the I/O to a logical
zero.
Output impedance must be lower than 500 ohms.
Under certain rare circumstances, when CSS = 00 in PMC_MCKR, and PA1 is set as an input
and a transition occurs on PA1, device malfunction might occur.
Do not transition PA1 as an input when CSS = 00 in PMC_MCKR.
Under certain rare circumstances, reprogramming the CSS value in the PMC_MCKR register
(i.e switching the main clock source) might generate malfunction of the device if the following
two actions occur simultaneously.
Note:
When changing CSS in the PMC_MCKR to switch from
Ensure that the processor is executing out of SRAM and ensure no transition occurs on PA1,
either as an input or output, starting from writing to the PMC_MCKR register until MCKRDY = 1.
1. Switching from:
2. Program code is being executed out of flash, or a transition is occurring on PA1, either
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
And
Problem Fix/Workaround
– PLL Clock to Slow Clock or
– PLL Clock to Main Clock or
– Main Clock to PLL Clock or
– Main Clock to Slow Clock
as an input or output.
– PLL Clock to Slow Clock or
– PLL Clock to Main Clock or
– Main Clock to PLL Clock or
– Main Clock to Slow Clock
This issue does not occur when transitioning from slow clock to main clock or from slow clock to
PLL clock.
SAM7S Series
627