The following menu's depend on the selections made for the Aux & ESC channels

If the ESC port is OFF and the Aux port is set to Sync Channel then the following menu selects the overhead assigned to the Aux port:

 

 

 

 

Sync Aux circuit o/h usage: [?]

 

 

1=Maximum 2:Custom

 

 

 

 

 

 

 

 

Change, Tx/Rx, ESC/Aux/BA Define (IBS) Aux usage Menu

MAXIMUM

The maximum 21/32nds of the overhead is allocated to the Aux channel. This

 

comprises TS16, TS32 bits 1, & 5-8, and TS48. Giving an Aux port synchronous

 

data rate of 4.375% of the main data rate. If used asynchronously (ie

 

oversampled as with the INTELSAT definition), the async rate may be up to 1%

 

of the main data channel rate, ie approx 600 Baud at 64kbps.

CUSTOM

This option is only available of the `Custom Features` feature is available

 

(standard P300-TCM). The overhead can be operator assigned to the Aux port,

 

varying the overhead as defined in the paragraph title "Custom Overhead

 

Allocation" a few paragraphs further on. If the ESC port is defined as Custom,

 

then this one screen allocates overhead between the Aux and ESC ports.

If the ESC port is set to High Rate Async and the Aux port is set to Sync Channel then the following menu allows the overhead assigned to the ESC port to be determined.

Async ESC: [?]

1=P230 compatible 2=Custom 3=All avail o/h{ after Aux}

Change, Tx/Rx, ESC/Aux/BA Define (IBS) ESC usage Menu

P230 COMP' The standard 20/32nds of the overhead is allocated to the ESC and this is compatible with earlier products such as the P230, P230D/I, and P1300/P1361 combination. The overhead allocated to the ESC is TS16, TS32 bits 5-8, and TS48. TS32 bit 1 is not used as this is reserved for the INTELSAT low rate ESC (on the Aux port if so configured). The ESC port provides an async channel with maximum Baud rate approximately the terrestrial rate / 23 (eg usable rates of 2400 Baud at 64 kbps and 9600 Baud at 256 kbps).

CUSTOM

This option is only available of the `Custom Features` feature is available

 

(standard P300-TCM). A subsequent screen allows the operator to assign the

 

overhead to the ESC port, varying the overhead as defined in the paragraph title

 

"Custom Overhead Allocation" which follows. If the Aux port is also set to Sync

 

Channel then this one screen allocates the overhead between the Aux and ESC

 

ports.

ALL AVAIL

All the available overhead is assigned to the ESC channel. if the Aux port is

 

defined as Sync Channel then the selection reads All Avail after Aux, and when

 

the operator has defined the overhead allocated to the Aux port, any remaining

 

is allocated to the ESC port. If using the Custom, IBS, Minimum overhead mode,

 

where the overhead rate varies to accommodate the ESC Baud rate defined, then

 

setting the ESC to All Avail maximises the proportion of the overhead available

 

to the ESC, and lowers the overhead addition to the minimum possible.

P300H

P300 Series Modem Installation and Operating Handbook

Page 79

Page 79
Image 79
Paradise P300 specifications Sync Aux circuit o/h usage ? =Maximum 2Custom, ALL Avail