If you fuck this up, it will fry the SRIB. READ THIS: The SRIB requires a 9v power supply Center Negative on the DC jack. You may need to open it up to verify this. NOTE: you must ensure your SRIB is a version D or later, as this has the larger SRAM chip that support the 1 meg radios. The CPS will write the firmware to the SRIB and then the SRIB will handle writing it to the radio once the CPS puts the radio in bootstrap mode. This is not only a level converter for TTL to serial, but contains a flash memory that will write the firmware to the radio. You will need an SRIB or Smart-Radio Interface Box. This is the laptop that just works, and it is modern enough to still "surf the web".
As of 2021 the D620/630/820/830 are going on ebay with 32bit XP and 2-4gb of ram for 100 dollars. You will need a windows XP 32 bit computer with a real serial port.