cx28500 Mindspeed Technologies, cx28500 Datasheet - Page 191

• Manufacturer Part Number: cx28500
• Description: Cx28500 Multichannel Synchronous Communications Controller
• Manufacturer: Mindspeed Technologies

2. Throughout the calculation, each column relates only to that specific set of channels with one exception. The
Table A-6.
28500-DSH-002-C
Number of Ch
Mem Available (KB)
Packet Length (bits)
Ext. Ch Rate (Kbps)
PCI Freq. (MHz)
Read Latency
Write Latency
PCI Bit Mode
Buffer Size
Rx Threshold
Tx Threshold
Int. Ch Rate (Kbps)
Int. Ch Rate (Kbps)
PCI Freq. (kHz)
Time to Read BD
Time to Read BD
Time to Update Status
MAXDATA
MAXDATA
Max L
Max L
Max L
Max L
Amnt Data Filled in L
Amnt Data Emptied on L
Spare Time (ms)
Spare Time (ms)
Utilization ABS Total represents the overall utilization of the CX28500.
ch
pci
ch
pci
(ms)
(ms)
(ms)
(ms)
Example One (1 of 2)
pci
Configuration
66 MHz PCI
pci
THR – RX
Mindspeed Proprietary and Confidential
BUFFLEN
THR – TX
Fch – RX
Mindspeed Technologies
Fch – TX
Average
Actual
PBIT
fpci
fpci
RX
RX
RX
RX
TX
TX
TX
TX
RX
TX
—
M
N
R
w
P
r
64-Bit PCI
Including Spare Time
168 x 1536K Channels
1568.68
1437.96
66000
0.508
0.076
0.554
0.076
0.431
0.477
1536
1592
168
352
796
796
352
352
120
110
64
66
64
0
0
4
4
3
Suggested
Calculated
CX28500 PCI Bus Latency and Utilization Analysis
32-Bit PCI
1568.68
1437.96
44-Byte Messages
66000
0.109
0.508
0.554
0.109
0.398
0.444
1536
1592
168
352
796
796
352
352
171
157
64
66
32
0
0
5
5
3
®
64-Bit PCI
6 x 44.21M Channels
45150.64
41388.09
44210
43723
21861
21861
66000
0.484
0.003
0.528
0.003
0.482
0.526
352
352
352
118
108
64
66
64
6
0
0
4
4
3
32-Bit PCI
45150.64
41388.09
44210
43723
21861
21861
66000
0.484
0.004
0.528
0.004
0.480
0.525
352
352
352
168
153
64
66
32
6
0
0
5
5
3
64-Bit PCI
186.607
248.810
186.551
248.754
168 x 4K Channels
66000
12-Byte Messages
0.056
0.056
1592
4.27
3.20
168
796
796
64
96
66
64
96
96
4
0
0
4
4
3
0
0
32-Bit PCI
186.607
248.810
186.538
248.741
66000
0.069
0.069
1592
4.27
3.20
168
796
796
96
64
66
32
96
96
4
0
0
5
5
3
0
0
176