Ricoh A250 Service Manual page 582

BIT SWITCHES
Bit Switch 17: CPS Code Used for G4 to G3 Fallback - 1
No. FUNCTION
0
Condition for fallback from G4 to G3
to Bits 0 to 6 of bit switch 17 contain a CPS code, and bits 0 to 6 of bit switch 18
6 contain another CPS code. If a CPS code is received which is the same as
either of these, communication will fall back from ISDN G4 mode to ISDN G3.
The CPS codes must be the same as those specified in table 4-13 of ITU-T
recommendation Q.931.
Examples: Bit 6 5 4 3 2 1 0
For the codes in bits 0 to 6 to be recognized, bit 7 of bit switch 17 must be 1.
Also, bit 0 of Communication Switch 07 must be at 0, or fallback from G4 to G3
will be disabled.
7
This bit determines whether fallback from G4 to G3 occurs on receipt of one of
the CPS codes programmed in bit switches 17 or 18, or on receipt of a certain
standard code.
0: Fallback occurs on receipt of any of the following CPS codes:
UK (EuroISDN mode) - #3, #18, #57, #58, # 63, # 65, #79, #88, and #127
Germany (1TR6 mode) - #3, #31, #53, #58, and #90
Others - #3, #65, and #88
1: Fallback from G4 to G3 occurs on receipt any of above CPS codes or one of
the CPS codes programmed in bit switches 17, 18, 1A, 1B, or 1C.
Bit Switch 18: CPS Code Used for G4 to G3 Fallback - 2
FUNCTION
0
Condition for fallback from G4 to G3
to See the explanation for bits 0 to 6 of bit switch 17
6
7 This bit determines the CPS code set for G4 to G3 fallback.
0: Fallback occurs on receipt of the CPS codes specified by bit switch 17 bit 7.
1: The CPS code set depends on bit switch 17, bit 7:
If bit switch 17 bit 7 is 0, fallback occurs on receipt of the UK CPS code set (#3,
#18, #57, #58, # 63, # 65, #79, #88, and #127) even if another country code is
programmed.
If bit switch 17 bit 7 is 1, fallback occurs on receipt of the UK CPS code set or
one of the CPS codes programmed in bit switches 17, 18, 1A, 1B, or 1C.
G4 to G3 fallback
Bit 0 of Communication Switch 07 must be at 0, or fallback from G4 to G3 will be
disabled.
The CPS codes for which fallback occurs are decided as follows.
• G4 bit switch 17, bit 7 – If set to '0', fallback occurs on receipt of a code from a
set that depends on the country code (UK, Germany, or Others). If set to '1',
fallback occurs for the 5 CPS codes programmed in bits 0 to 6 of G4 bit switches
17, 18, 1A, 1B, and 1C, in addition to the country code set.
Note that if G4 bit switch 18, bit 7 is set to '1', the country code CPS code set
that is used is always the UK set, regardless of the country code setting.
A250
1 0 0 0 0 0 1 CPS code 65
1 0 1 1 0 0 0 CPS code 88
COMMENTS
COMMENTS
1-12 SM