User guide

DS3134

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0000000010 (002h) = High Water Mark is 2 Blocks

0111111111 (1FFh) = High Water Mark is 511 Blocks

1111111111 (3FFh) = High Water Mark is 1023 Blocks

76543210

HCID7 HCID6 HCID5 HCID4 HCID3 HCID2 HCID1 HCID0

15 14 13 12 11 10 9 8

IAB IARW n/a n/a n/a n/a n/a n/a

Note: Bits that are underlined are read only, all other bits are read-write; default value for all bits is 0.

Bits 0 to 7 / HDLC Channel ID (HCID0 to HCID7).

00000000 (00h) = HDLC Channel Number 1

11111111 (FFh) = HDLC Channel Number 256

Bit 14 / Indirect Access Read/Write (IARW). When the host wishes to write data to the internal

Transmit Starting Block Pointer RAM, this bit should be written to a zero by the host. This causes the

device to take the data that is currently present in the TFSBP register and write it to the channel location

indicated by the HCID bits. When the device has completed the write, the IAB will be set to zero.

Note: The TFSBP is a write only register. Once this register has been written to and operation started,

DS3134 internal state machine will change the value in this register.

Bit 15 / Indirect Access Busy (IAB). When an indirect read or write access is in progress, this read only

bit will be set to a one. During a read operation, this bit will be set to a one until the data is ready to be

read. It will be set to zero when the data is ready to be read. During a write operation, this bit will be set

to a one while the write is taking place. It will be set to zero once the write operation has completed.

76543210

TSBP7 TSBP6 TSBP5 TSBP4 TSBP3 TSBP2 TSBP1 TSBP0

15 14 13 12 11 10 9 8

n/a n/a n/a n/a n/a n/a TSBP9 TSBP8

Note: Bits that are underlined are read only, all other bits are read-write.