Rainbow Electronics DS2143Q - Manual (Page 24)

DS2143/DS2143Q
031397 24/40
Sa5 TNAF.3 Additional Bit 5.
Sa6 TNAF.2 Additional Bit 6.
Sa7 TNAF.1 Additional Bit 7.
Sa8 TNAF.0 Additional Bit 8.
12.0 LINE INTERFACE CONTROL FUNCTION
The DS2143 can control line interface units that contain
serial ports. When Control Register Bytes 1 or 2 (CRB1,
CRB2) are written to, the DS2143 will automatically
write this data serially (LSB first) into the line interface by
creating a chip select, serial clock and serial data via the
LI_CS, LI_SCLK and LI_SDI pins respectively. This
control function is driven off of the RCLK and it must be
present for proper operation. Registers CRB1 and
CRB2 can only be written to, they cannot be read from.
Writes to these registers must be at least 20
µ s apart.
See Section 13 for timing information.
CRB1: CONTROL REGISTER BYTE 1 (Address=18 Hex)
CRB2: CONTROL REGISTER BYTE 2 (Address=19 Hex)
(MSB) (LSB)
CR7 CR6 CR5 CR4 CR3 CR2 CR1 CR0
CR7 CR6 CR5 CR4 CR3 CR2 CR1 CR0
SYMBOL POSITION NAME AND DESCRIPTION
CR1 CRB1.0 LSB of Control Register Byte 1
CR7 CRB2.7 MSB of Control Register Byte 2
13.0 TIMING DIAGRAMS
RECEIVE SIDE TIMING
15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 FRAME# 16 1 2 3 4 5 6 14
RSYNC 1
RSYNC 2
RCLK 3
RLINK 4
NOTES:
1. RSYNC in the frame mode (RCR1.6=0).
2. RSYNC in the multiframe mode (RCR1.6=1).
3. RLCLK is programmed to output just the Sa4 bit.
4. RLINK will always output all five Sa bits as well as the rest of the receive data stream.
5. This diagram assumes the CAS MF begins with the FAS word.
CRB1
CRB2