Hi Mert,
The PGA308 has different modes of operation as discussed on Chapter 5 of the PGA308 User Guide: One-Wire Write Mode, One-Wire Read Mode, OTP Program Mode, Standalone Mode, 1W Connected to VOUT Program Mode, Virtual Software Lock Mode, Software Lock Mode, and Shutdown mode.
When setting the SWL[2:0] register to '101' allows you direct Read/Write RAM register control of the PGA308 in the Software Lock Mode:
Software Lock Mode allows you to control the PGA308 RAM directly by enabling the One-Wire interface, disabling any One-Wire timeouts, and disabling the checksum check normally performed between the CHSR Register and CHKS Register. This mode is designed for microcontroller control of the PGA308 through a microcontroller UART interface. It allows the PGA308 to be controlled as a flexible data acquisition front-end.
The user can select to load the settings of one of the seven OTP user banks and load them into RAM; and/or the user can program the RAM contents directly. To access this mode, the SWL[2:0] register must be set to '101' as shown on table 7-44 (other settings of SWL registers default to standalone OTP mode, and the POR value of this register is '000'). Please refer to pages 72-74 of the PGA308 User Guide, and the flow diagram on page 73 (figure 5-14).
Thank you and Regards,
Luis
