TMC2074-NU SMSC, TMC2074-NU Datasheet - Page 21

• Manufacturer Part Number: TMC2074-NU
• Description: IC CTRL CIRC 128VTQFP PERIPH MOD
• Manufacturer: SMSC
• Series: CircLink™r

Specifications of TMC2074-NU

• Controller Type: I/O Controller
• Interface: Transceiver
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 40mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 128-TQFP, 128-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 638-1024

Dual Mode CircLink™ Controller
Datasheet
1.6.8
1.6.9
1.6.10 Node ID Setup
SMSC TMC2074
Page Size Selection
(PS[1:0]: Pin/Register)
Select page size per packet. The maximum number of nodes depends on the page size selection since the
packet buffer size is limited to 1 kByte. Page size can be selected by settings using register bits INIMODE
(bit 9); 0: selects pin, 1: selects register (The default is 0).
Maximum Node (MAXID) Number Setup
(MAXID[4:0]: Pin/Register)
The maximum node ID is set based on the number of nodes on the network. All nodes in each CircLink
network, therefore, should have the same maximum node ID. This minimizes the time required to
reconfigure the network. There are two methods to specify the maximum node ID, Either through pin or
register settings depending on INIMODE (bit 9); 0: selects pin, 1: selects register (The default is 0). If the
nDIAG pin is set to L as the exception, however, the maximum node ID is automatically set to the largest
value. For more details, refer to section 2.11 - Diagnostic Mode.
(NID[4:0]: Pin/Register)
Set node ID. A unique number must be assigned to each node in the network with ascending order starting
from ID=01. ID = 00 and an ID larger than the maximum node ID are not valid. There are two methods to
assign the node ID, either through pin or register, settings depending on INIMODE (bit 7) 0: selects pin, 1:
select register (default is 0).
MAXID[4:0] determines the maximum node ID value. The token will be passed only around the nodes
whose IDs are equal to or less than the maximum ID value. . In the CircLink network, a node whose
MAXID[4:0] and NID[4:0] matches is the node initiating the token passing.. Even if this particular node is
absent from the network, the network reconfiguration time is greatly reduced because the network will be
only reconfigured by the nodes with IDs less than MAXID[4:0]. Since the maximum number of nodes is
fixed to MAXID[4:0] in a CircLink network, the original priority timer of ARCNET, (255 – ID) x 146 μs*,
which determines the time required for network reconfiguration, is modified to (MAXID[4:0]-ID) x 146 μs,
greatly reducing network reconfiguration time. Refer to section 2.4.2 - Reduction of Network
Reconfiguration Time for more details.
* 146 μs is defined under operation at 2.5 Mbps based on ARCNET protocol. That number is half at 5
Mbps.
PS[1:0]
00
01
10
11
Page Size
256 Byte
128 Byte
64 Byte
32 Byte
DATASHEET
Page 21
Max Node Number
15 Node
31 Node
3 Node
7 Node
Revision 0.2 (10-23-08)