ATAM862P-TNSY4D Atmel, ATAM862P-TNSY4D Datasheet - Page 79

• Manufacturer Part Number: ATAM862P-TNSY4D
• Description: IC MCU FLASH 4K TX 433MHZ 24SSOP
• Manufacturer: Atmel

Specifications of ATAM862P-TNSY4D

• Applications: UHF ASK/FSK
• Core Processor: MARC4
• Program Memory Type: FLASH (4 kB)
• Controller Series: MARC4 4-Bit
• Ram Size: 256 x 4
• Interface: SSI
• Number Of I /o: 11
• Voltage - Supply: 1.8 V ~ 4 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SSOP
• Processor Series: ATAM862x
• Core: MARC4
• Data Bus Width: 4 bit
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

23.8.9
4551G–4BMCU–07/07
Modulation and Demodulation
If the shift register is used together with Timer 2 or Timer 3 for modulation or demodulation pur-
poses, the 8-bit synchronous mode must be used. In this case, the unused Port 4 pins can be
used as conventional bi-directional ports.
The modulation and demodulation stages, if enabled, operate as soon as the SSI is activated
(SIR = 0) and cease when deactivated (SIR = 1).
Due to the byte-orientated data control, the SSI (when running normally) generates serial bit
streams which are submultiples of 8 bits. An SSI output masking (OMSK) function permits; how-
ever, the generation of bit streams of any length. The OMSK signal is derived indirectly from the
4-bit prescaler of the Timer 2 and masks out a programmable number of unrequired trailing data
bits during the shifting out of the final data word in the bit stream. The number of non-masked
data bits is defined by the value pre-programmed in the prescaler compare register. To use out-
put masking, the modulator stop mode bit (MSM) must be set to "0" before programming the
final data word into the SSI transmit buffer. This in turn, enables shift clocks to the prescaler
when this final word is shifted out. On reaching the compare value, the prescaler triggers the
OMSK signal and all following data bits are blanked.
Figure 23-23. SSI Output Masking Function
T1OUT
SYSCL
TOG2
POUT
SCL
/2
SC
CL2/1
Shift_CL
4-bit counter 2/1
Compare 2/1
SO
CM1
MSB
SSI-control
8-bit shift register
LSB
Control
Timer 2
ATAM862-4
OMSK
SI
Output
SO
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