ALOHA Cabled Observatory
|
ALOHA Cabled Observatory
|
|
|
Aloha Cabled Observatory Engineering Documentation Shore Station PCI Manchester
FO Link (Manchester) Digital serial Manchester encoded data are received from and sent to the muldex board (6. (a) The received data in 64-bit frames originate in the Proof Module on the ocean floor. The first 8 bits are frame sync bits, two channels of embedded slow RS232 serial (one bit each), and 1 “clock lock” status bit. The next 24 bits are digitized “left” channel audio, followed by 8 null bits and ending with 24 bits of digitized “right” channel audio. The 64 bit frame is Manchester decoded into individual components at the cable station. The two RS232 bits go to TTL to RS232 drivers and then to the serial ports on a terminal server. The two 24-bit serial digital audio bits are sent to both the serial DAC (2) and the FIFO’s (3). The single status bit is monitored directly by the PCI interface (4). (b) The sent data is originated at a user console on any networked computer and sent to the terminal server. The RS232 driver converts the RS232 comm to TTL and embeds it into the 64 bit frame going to the proof module. Repeated redundant bits of one channel are in the first 32 bits, and repeated redundant bits of the seconds channel are in the last 32 bits.
Rev: 08/10/2007
|
|
|
