\item[0x88 - 0x8B: Timeouts $\dagger$] One register for each TrbNet channel. Each bit gives the status of one port: 1 if there was a timeout on this port, 0 otherwise. These registers are cleared after being read. If a bit in these registers is set, it also causes the corresponding link LED to flash (approx. 2 Hz, 25\% off).
\item[0x8C - 0x8F: Waiting for ACK] One register for each TrbNet channel. Each bit gives the status of one port: 1 if data transmission on this port is stopped because the receiver did not acknowledge previous EOB words, 0 otherwise.
\item[0x90: Link error status] One bit for each port. 0 if normal operation / inactive, 1 in cave of error (e.g. code violation).
+ \item[0x98 - 0x99: Hub Logic Status] Hub Status register. 16 Bit per channel
+ \item[0x9F IPU Mismatch] Data channel mismatch (of trigger number, trigger info or trigger count). One bit per port
\item[0xA0 -- 0xA3: Error-/Status-Bits $\dagger$] One register for each TrbNet channel. Each register is the last Error-/Status-Bits, combined from all ports.
\item[0xA4: Slow Control Error $\dagger$] One bit for each port. 1 if either one of the Errorbits 1,3,6 on the slow control channel have been set before. This register is cleared after being read.
\item[0xA5: Endpoint reached] One bit for each port. 1 if this port returned the ``Endpoint reached'' bit in the status word set in the last slow control access, 0 otherwise. This information can be used to track a single board in the network: First a read access using the network address of the selected board has to be done. Immediately afterward this register can be read. To secure this non-atomic operation, the register is only updated if the board also return the ``don't understand' bit, e.g. after a read memory access to register 0.
5555 & SEB & Dummy Address used in headers generated by SubEventBuilders \\
8000 - 80FF & Central Hub & central hub\\
8100 - 81FF & MDC Hub & Hub for inner MDC (3rd digit 0) or outer MDC (3rd digit 1)\\
-8300 - 83FF & RICH Hubs & Hubs for RICH, last digit: sector divided by 2 \\
-8400 - 84FF & RPC Hubs & Hubs for RPC, last digit: sector divided by 3 \\
+8300 - 83FF & RICH Hubs & Hubs for RICH, 3rd digit: sector divided by 2 \\
+8400 - 84FF & RPC Hubs & Hubs for RPC, 3rd digit: sector divided by 3 \\
8500 - 85FF & Shower Hub & \\
8600 - 86FF & TOF Hub & \\
8700 - 87FF & Forward Wall Hub & \\