Rainbow Electronics DS26519 - Manual (Page 139)

DS26519 16-Port T1/E1/J1 Transceiver
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Register Name: GTCCR3
Register Description: Global Transceiver Clock Control Register 3
Register Address: 00F4h
Channels: 1 to 8
Bit
# 7 6 5 4 3 2 1 0
Name — RSYSCLKSEL TSYSCLKSEL TCLKSEL CLKOSEL3 CLKOSEL2 CLKOSEL1 CLKOSEL0
Default 0 0 0 0 0 0 0 0
Bit 6: RSYSCLKn Select (RSYSCLKSEL)
0 = Use RSYSCLKn pins for each receive system clock (Channels 1–8).
1 = Use BPCLK1 as the master clock for all eight receive system clocks (Channels 1–8).
Bit 5: TSYSCLKn Select (TSYSCLKSEL)
0 = Use TSYSCLKn pins for each transmit system clock (Channels 1–8).
1 = Use BPCLK1 as the master clock for all eight transmit system clocks (Channels 1–8).
Bit 4: TCLKn Select (TCLKSEL)
0 = Use TCLKn pins for each of the transmit clock (Channels 1–8).
1 = Use REFCLKIO as the master clock for all eight transmit clocks (Channels 1–8).
Bits 3 to 0: Clock Out Frequency Select (CLKOSEL[3:0]. CLKO output pin will use MCLK (1.544MHz or
2.048MHz or scaled version) as its reference. The following table shows how to configure for each frequency. For
best jitter performance use a 2.048MHz oscillator for MCLK.
CLKOSEL[3:0] CLKO (kHz)
0000 2048
0001 4096
0010 8192
0011 16384
0100 1544
0101 3088
0110 6176
0111 12352
1000 1536
1001 3072
1010 6144
1011 12288
1100 32
1101 64
1110 128
1111 256