NEC UPD98413 User Manual page 41

A1 A1 A1
(F6) (F6) (F6)
B1
(--)
D1
(00)
H1 H1 H1
(62) (93) (93)
B2 B2 B2
(--) (--) (--)
D4
(00)
D7
(00)
D10
(00)
S1 Z1 Z1
(00) (00) (00)
Remark Any value can be also inserted from the OH interface to the unused OH byte area. Inserting byte
data from the OH interface takes precedence over the changing of this mode.
(b) Fixed Stuff byte
In the second through 4th columns of SPE are Fixed Stuff bytes. In the default mode, all FFH is inserted.
This value can be changed to all 00H by using the FSBM bit of the MDPOHT register.
(c) Changing inserted value of 5th byte of Z0 and those that follow
In the default mode, 02H to 0CH are sequentially stored to the Z0 byte of 11. These values can be changed
to AAH from the 4th byte to the 11th byte of the Z0 byte by using the Z0M bit of the MDSOHT register.
Default
AA mode
(d) Pointer generation
The pointer on the fourth line of TOH consists of three types of bytes, H1, H2, and H3, and it is used as an
address to identify the first byte (J1 byte of POH) of SPE.
The transmit frame transmitted by the µPD98413 changes the position of neither POH (path overhead) nor
the J1 byte. Therefore, the pointer value stored into the H1 and H2 bytes is always 20AH = "1000001010",
and NDF is always fixed to "0110" and disabled. The SS bits that are the bit 5 and bit 6 of the H1 byte are
"00" by default. Their values can be changed by setting the SS[1:0] bits of the MDPTRT register.
Because Frequency Justification (stuff operation) is not requested at the transmission side, payload data is
not set in the H3 byte that is used as Negative Stuff byte. Instead, the H3 byte is set to all zeros and
transmitted.
CHAPTER 3 FUNCTIONAL OUTLINE
Figure 3-5. Unused OH Byte
A2 A2 A2 J0
(28) (28) (28) (01)
E1 F1
(00) (00)
D2 D3
(00) (00)
H2 H2 H2 H3
(0A) (FF) (FF) (00)
K1 K2
(00) (00)
D5 D6
(00) (00)
D8 D9
(00) (00)
D11 D12
(00) (00)
Z2 Z2 M1 Z2 E2
(00) (00) (00) (--) (00)
Figure 3-6. Inserted Value of Z0 Byte
4 bytes
J0 Z0 Z0 Z0 Z0 Z0
0 1 2 3 4 5
01 02 03 04 05 06 07 08 09 0A 0B 0C
01 02 03 04 AA AA AA AA AA AA AA AA
PRELIMINARY
Z0 Z0 J1
(02) (0C) (00)
Fixed
B3
Stuff
(--)
Byte
C2
Area
(13)
H3 H3 G1
(00) (00) (--)
F2
(00)
H4
(00)
Z3
(00)
Z4
(00)
Z5
(00)
8 bytes
Z0 Z0 Z0 Z0 Z0 Z0
6 7 8 9 10 11
NEC confidential and Proprietary
41