RFM219SW Datasheet, PDF (23/35 Pages) List of Unclassifed Manufacturers – Wireless Alarm and Security Systems

RFM219SW
For those which are cleared by the MCU, each of them has an ‘EN’ bit and a ‘CLR’ register bit. For example, the Sync Word
detection pass interrupt is only enabled when the ‘SYNC_PS_EN’ bit is set to 1, and the interrupt is cleared by setting the
‘SYNC_PS_CLR’ bit to 1. The MCU does not need to set the ‘SYNC_PS_CLR’ bit back to 0 after setting it to 1, because this bit
automatically clears itself once the interrupt is cleared.
The number of available interrupts and their mappings are different in direct mode and buffer mode. For more details of the GPO
controls, please refer to chapter 5.11 User Registers.
5.9 Data Handling
A data path consists of a packet handler and a 32-byte FIFO which is responsible for delivering the data from the demodulator to
the external MCU. It supports 3 data access modes: direct, buffer and packet mode.
5.9.1 Direct Mode
In direct mode, the data from the demodulator’s output is directly sent out to the MCU via the DOUT, which can be mapped to
GPO 1, 3 or 4. The synchronization clock is output via the DCLK, which can be mapped to GPO 2 or 4. The optional preamble
and sync word detection interrupts are supported upon requirements.
EEPROM (Optional)
RF
DEMOD
clock
1
data
1
Preamble
(Optional)
Sync
(Optional)
clock
1
data
1
User Registers
DCLK
CSB
SPI
SCL
SDA
INT1/INT2
DOUT
Figure 20. Data Path of Direct Mode
The data receiving works independently of the preamble and sync word detection in the direct mode. This means, no matter
whether a valid preamble or a sync word is detected or not, the demodulated data will be transparently output on the DOUT.
The sync clock is generated with two purposes: removing the glitches exist on the data output, and assisting the external MCU to
sample the data at the correct instance.
1 Symbol
Raw Data
Internal
Sync Clock
Output Data
Output
Sync Clock
Figure 21. Demodulated Data and Sync Clock Timing Characteristics
E-mail:[e-mail]
Rev 1.0 | Page 23/35
www.hoperf.com