SAM7S128 Atmel Corporation, SAM7S128 Datasheet - Page 14
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SAM7S128
Manufacturer Part Number
SAM7S128
Description
Manufacturer
Atmel Corporation
Specifications of SAM7S128
Flash (kbytes)
128 Kbytes
Pin Count
64
Max. Operating Frequency
55 MHz
Cpu
ARM7TDMI
Hardware Qtouch Acquisition
No
Max I/o Pins
32
Ext Interrupts
32
Usb Transceiver
1
Usb Speed
Full Speed
Usb Interface
Device
Spi
1
Twi (i2c)
1
Uart
3
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)
32
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
6. I/O Lines Considerations
6.1
6.2
6.3
6.4
6.5
14
JTAG Port Pins
Test Pin
Reset Pin
ERASE Pin
PIO Controller A Lines
SAM7S Series Summary
TMS, TDI and TCK are schmitt trigger inputs. TMS and TCK are 5-V tolerant, TDI is not. TMS,
TDI and TCK do not integrate a pull-up resistor.
TDO is an output, driven at up to VDDIO, and has no pull-up resistor.
The JTAGSEL pin is used to select the JTAG boundary scan when asserted at a high level. The
JTAGSEL pin integrates a permanent pull-down resistor of about 15 kΩ to GND, so that it can be
left unconnected for normal operations.
The TST pin is used for manufacturing test, fast programming mode or SAM-BA Boot Recovery
of the SAM7S Series when asserted high. The TST pin integrates a permanent pull-down resis-
tor of about 15 kΩ to GND, so that it can be left unconnected for normal operations.
To enter fast programming mode, the TST pin and the PA0 and PA1 pins should be tied high
and PA2 tied to low.
To enter SAM-BA Boot Recovery, the TST pin and the PA0, PA1 and PA2 pins should be tied
high for at least 10 seconds. Then a power cycle of the board is mandatory.
Driving the TST pin at a high level while PA0 or PA1 is driven at 0 leads to unpredictable results.
The NRST pin is bidirectional with an open drain output buffer. It is handled by the on-chip reset
controller and can be driven low to provide a reset signal to the external components or asserted
low externally to reset the microcontroller. There is no constraint on the length of the reset pulse,
and the reset controller can guarantee a minimum pulse length. This allows connection of a sim-
ple push-button on the pin NRST as system user reset, and the use of the signal NRST to reset
all the components of the system.
The NRST pin integrates a permanent pull-up resistor to VDDIO.
The ERASE pin is used to re-initialize the Flash content and some of its NVM bits. It integrates a
permanent pull-down resistor of about 15 kΩ to GND, so that it can be left unconnected for nor-
mal operations.
Programming of this pull-up resistor is performed independently for each I/O line through the
PIO controllers.
5V-tolerant means that the I/O lines can drive voltage level according to VDDIO, but can be
driven with a voltage of up to 5.5V. However, driving an I/O line with a voltage over VDDIO while
the programmable pull-up resistor is enabled will create a current path through the pull-up resis-
• All the I/O lines PA0 to PA31on SAM7S512/256/128/64/321 (PA0 to PA20 on SAM7S32) are
• All the I/O lines PA0 to PA31 on SAM7S161 (PA0 to PA20 on SAM7S16) are not 5V-tolerant
5V-tolerant and all integrate a programmable pull-up resistor.
and all integrate a programmable pull-up resistor.
6175JS–ATARM–28-Jul-11