SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
To allow complete software flexibility when transmitting and receiving infrared data packets, the SIR free-format (FF) mode is a subfunction of the existing SIR mode. In FF mode, all frames going to and from the FIFO buffers are untouched with respect to appending and removing control characters and CRC values.
The FF mode corresponds to a UART mode with a pulse modulation of 3/16 of baud rate pulse width.
For example, a normal SIR packet has BOF control and CRC error-checking data appended (transmitting) or removed (receiving) from the data going to and from the FIFOs.
Figure 13-54 shows SIR FF mode.
In SIR FF mode, the Host CPU software must construct (that is, encode and decode) the entire FIFO data packet.
The SIR Free Format mode is selected by setting the module in UART mode (MDR1[2:0] = 000) and the MDR2[3] register bit to one to allow the pulse shaping. As the bit format is to remain the same, some UART mode configuration registers need to be set at specific value:
The features defined through MDR2[6] and ACREG[5] are also supported, however: