Setting clock rate

ramjet666 · June 2007

Hi,

I have 2 routers (1601/1603) connected via serial cable dce/dte routing is good and I can ping from end to end.

I just wanted to improve the speed of the serial link.

If I try to set any clock rate on the DCE side nothing seems to show up with either 'show controllers s 0' or 'sh run'.

Should I see a 'clock rate ...' when viewing a 'sh run' as under s0 is just ip info?
Should I see the rate set with a 'sh controllers s 0'?

When you enter 'clock rate ...' and exit int config is it altered immediatly? Or do you have to 'shutdown' then 'no shutdown'?

The 1601 has serial on board where as the 1603 is a WIC-1T.

Cheers!
Roger.

blackmage439 · June 2007

The clock rate should show up in a show int command. There seems to be some disagreement on this, but apparently on some routers, the clock rate will not show up if it set to the default.

The changes made should be immediate, but if you wanted to be sure, go ahead and do a shutdown.

Netstudent · June 2007

yes and Yes....
You should see clock rate in the show run output.
You should also see it in the show controller serial 0 command

here is a sample output:
prasit#
show controllers serial 0

HD unit 1, idb = 0xF22E4, driver structure at 0xF7778

buffer size 1524 HD unit 0 1, V.35 DCE cable, clockrate 64000

As black said, the changes will be immediate, however there is no need for clock rate if the interface is disabled. If the interface has not been brought up (No shut), then there is no data exchange, if there is no data transmission then no need for a clock rate. Basically the clock rate will not be used untill the interface is brought up. If the interface is already enabled, and you set the clock rate, there is no need to disabble then re-enable the interface. The clock rate command will synchronize the already enabled interface.

ramjet666 · June 2007

Hmm, take a look at this:

ROUTER-A-1601#sh controllers s 0

QUICC Serial unit 0
idb at 0x213C54C, driver data structure at 0x213E1D8
SCC Registers:
General [GSMR]=0x2:0x00000030, Protocol-specific [PSMR]=0x0
Events [SCCE]=0x0000, Mask [SCCM]=0x001F, Status [SCCS]=0x0006
Transmit on Demand [TODR]=0x0, Data Sync [DSR]=0x7E7E
Interrupt Registers:
Config [CICR]=0x00368461, Pending [CIPR]=0x00004004
Mask   [CIMR]=0xC8000012, In-srv  [CISR]=0x00000000
Command register [CR]=0x690
Port A [PADIR]=0x0000, [PAPAR]=0xCEC3
       [PAODR]=0x0000, [PADAT]=0x37FE
Port B [PBDIR]=0x00F13E, [PBPAR]=0x0010CE
       [PBODR]=0x000000, [PBDAT]=0x0348DD
Port C [PCDIR]=0x000E, [PCPAR]=0x0000
       [PCSO]=0x0830,  [PCDAT]=0x03C0, [PCINT]=0x0000
DTE V.35 serial cable attached.

SCC GENERAL PARAMETER RAM (at 0xFF00F00)
Rx BD Base [RBASE]=0x560, Fn Code [RFCR]=0x18
Tx BD Base [TBASE]=0x5A0, Fn Code [TFCR]=0x18
Max Rx Buff Len [MRBLR]=1528
Rx State [RSTATE]=0x18008240, BD Ptr [RBPTR]=0x578
Tx State [TSTATE]=0x18000348, BD Ptr [TBPTR]=0x5A0

SCC HDLC PARAMETER RAM (at 0xFF00F3[IMG]https://us.v-cdn.net/6030959/uploads/images/smilies/icon_cool.gif[/IMG]
CRC Preset [C_PRES]=0xFFFF, Mask [C_MASK]=0xF0B8
Errors: CRC [CRCEC]=0, Aborts [ABTSC]=0, Discards [DISFC]=0
Nonmatch Addr Cntr [NMARC]=0
Retry Count [RETRC]=0
Max Frame Length [MFLR]=1526
Rx Int Threshold [RFTHR]=0, Frame Cnt [RFCNT]=63941
User-defined Address 0000/0000/0000/0000
User-defined Address Mask 0x0000


buffer size 1524
BRGC1=101B0, BRGC2=0, BRGC3=0, BRGC4=0
modem_signal_addr FF01566
MASK: DSR=1, DTR=2,RTS=8.CTS=400,DCD=800
txbrgc=FF015FC, rxbrgc=FF015FC
BRG [DTE]: rx_sicr_clk=7, tx_sicr_clk=6
BRG [DCE]: rx_sicr_clk=7, tx_sicr_clk=3
CLK SRC: sync=4000, async=4000
RX ring with 8 entries at 0xFF00560, Buffer size 1524
Rxhead = 0xFF00578 (3), Rxp = 0x213E200 (3)
00 pak=0x214552C buf=0x279755C status=9000 pak_size=0
01 pak=0x2145D48 buf=0x2798990 status=9000 pak_size=0
02 pak=0x2144D10 buf=0x2796128 status=9000 pak_size=0
03 pak=0x2145278 buf=0x2796EA0 status=9000 pak_size=0
04 pak=0x2145FFC buf=0x279904C status=9000 pak_size=0
05 pak=0x2144FC4 buf=0x27967E4 status=9000 pak_size=0
06 pak=0x21457E0 buf=0x2797C18 status=9000 pak_size=0
07 pak=0x21462B0 buf=0x2799708 status=B000 pak_size=0

TX ring with 2 entries at 0xFF005A0, tx_count = 0
tx_head = 0xFF005A0 (0), head_txp = 0x213E250 (0)
tx_tail = 0xFF005A0 (0), tail_txp = 0x213E250 (0)
00 pak=0x0000000 buf=0x0000000 status=0000 pak_size=0
01 pak=0x0000000 buf=0x0000000 status=2000 pak_size=0
QUICC SCC specific errors:
0 input aborts on receiving flag sequence
0 throttles, 0 enables
0 overruns
0 transmitter underruns
0 transmitter CTS losts

ROUTER-A-1601#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
ROUTER-A-1601(config)#int s0
ROUTER-A-1601(config-if)#clock rate ?
        Speed (bits per second)
  1200
  2400
  4800
  9600
  19200
  38400
  56000
  64000
  72000
  125000
  148000
  250000
  500000
  800000
  1000000
  1300000
  2000000
  4000000

  <300-4000000>    Choose clockrate from list above

ROUTER-A-1601(config-if)#clock rate 125000
ROUTER-A-1601(config-if)#^Z
ROUTER-A-1601#
07:57:04: %SYS-5-CONFIG_I: Configured from console by console

ROUTER-A-1601#show controllers s 0

QUICC Serial unit 0
idb at 0x213C54C, driver data structure at 0x213E1D8
SCC Registers:
General [GSMR]=0x2:0x00000030, Protocol-specific [PSMR]=0x0
Events [SCCE]=0x0000, Mask [SCCM]=0x001F, Status [SCCS]=0x0006
Transmit on Demand [TODR]=0x0, Data Sync [DSR]=0x7E7E
Interrupt Registers:
Config [CICR]=0x00368461, Pending [CIPR]=0x00004004
Mask   [CIMR]=0xC8000012, In-srv  [CISR]=0x00000000
Command register [CR]=0x690
Port A [PADIR]=0x0000, [PAPAR]=0xCEC3
       [PAODR]=0x0000, [PADAT]=0xF7FE
Port B [PBDIR]=0x00F13E, [PBPAR]=0x0010CE
       [PBODR]=0x000000, [PBDAT]=0x0348DD
Port C [PCDIR]=0x000E, [PCPAR]=0x0000
       [PCSO]=0x0830,  [PCDAT]=0x03C0, [PCINT]=0x0000
[b]DTE V.35 serial cable attached.[/b]

SCC GENERAL PARAMETER RAM (at 0xFF00F00)
Rx BD Base [RBASE]=0x560, Fn Code [RFCR]=0x18
Tx BD Base [TBASE]=0x5A0, Fn Code [TFCR]=0x18
Max Rx Buff Len [MRBLR]=1528
Rx State [RSTATE]=0x18008240, BD Ptr [RBPTR]=0x568
Tx State [TSTATE]=0x18000348, BD Ptr [TBPTR]=0x5A8

SCC HDLC PARAMETER RAM (at 0xFF00F3[IMG]https://us.v-cdn.net/6030959/uploads/images/smilies/icon_cool.gif[/IMG]
CRC Preset [C_PRES]=0xFFFF, Mask [C_MASK]=0xF0B8
Errors: CRC [CRCEC]=0, Aborts [ABTSC]=0, Discards [DISFC]=0
Nonmatch Addr Cntr [NMARC]=0
Retry Count [RETRC]=0
Max Frame Length [MFLR]=1526
Rx Int Threshold [RFTHR]=0, Frame Cnt [RFCNT]=63911
User-defined Address 0000/0000/0000/0000
User-defined Address Mask 0x0000


buffer size 1524
BRGC1=101B0, BRGC2=0, BRGC3=0, BRGC4=0
modem_signal_addr FF01566
MASK: DSR=1, DTR=2,RTS=8.CTS=400,DCD=800
txbrgc=FF015FC, rxbrgc=FF015FC
BRG [DTE]: rx_sicr_clk=7, tx_sicr_clk=6
BRG [DCE]: rx_sicr_clk=7, tx_sicr_clk=3
CLK SRC: sync=4000, async=4000
RX ring with 8 entries at 0xFF00560, Buffer size 1524
Rxhead = 0xFF00568 (1), Rxp = 0x213E1F8 (1)
00 pak=0x2145FFC buf=0x279904C status=9000 pak_size=0
01 pak=0x21457E0 buf=0x2797C18 status=9000 pak_size=0
02 pak=0x21462B0 buf=0x2799708 status=9000 pak_size=0
03 pak=0x214552C buf=0x279755C status=9000 pak_size=0
04 pak=0x2145D48 buf=0x2798990 status=9000 pak_size=0
05 pak=0x2144D10 buf=0x2796128 status=9000 pak_size=0
06 pak=0x2145A94 buf=0x27982D4 status=9000 pak_size=0
07 pak=0x2145278 buf=0x2796EA0 status=B000 pak_size=0

TX ring with 2 entries at 0xFF005A0, tx_count = 0
tx_head = 0xFF005A8 (1), head_txp = 0x213E254 (1)
tx_tail = 0xFF005A8 (1), tail_txp = 0x213E254 (1)
00 pak=0x0000000 buf=0x0000000 status=0000 pak_size=0
01 pak=0x0000000 buf=0x0000000 status=2000 pak_size=0
QUICC SCC specific errors:
0 input aborts on receiving flag sequence
0 throttles, 0 enables
0 overruns
0 transmitter underruns
0 transmitter CTS losts

ROUTER-A-1601#sh run
Building configuration...

Current configuration : 668 bytes
!
version 12.2
no parser cache
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname ROUTER-A-1601
!
logging rate-limit console 10 except errors
!
ip subnet-zero
!
no ip dhcp-client network-discovery
!
!
!
interface Ethernet0
 ip address 192.168.0.220 255.255.255.0
!
interface Serial0
 ip address 192.168.20.1 255.255.255.0
!

[output cut]

ROUTER-A-1601#

It just does not seem to notice the 'clock rate' setting?

blackmage439 · June 2007

Netstudent,

I meant to imply resetting the interface by issuing a shutdown then no shutdown. My mistake.

ramjet,

Can you show us a show int s0?

ramjet666 · June 2007

Can you show us a show int s0?

Sure:

ROUTER-A-1601#show int s0
Serial0 is up, line protocol is up
  Hardware is QUICC Serial
  Internet address is 192.168.20.1/24
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation HDLC, loopback not set
  Keepalive set (10 sec)
  Last input 00:00:02, output 00:00:02, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/0 (size/max total/threshold/drops)
     Conversations  0/3/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
     Available Bandwidth 1158 kilobits/sec
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     12457 packets input, 2612593 bytes, 0 no buffer
     Received 3260 broadcasts, 0 runts, 0 giants, 0 throttles
     1 input errors, 0 CRC, 1 frame, 0 overrun, 0 ignored, 0 abort
     13636 packets output, 935105 bytes, 0 underruns
     0 output errors, 0 collisions, 32 interface resets
     0 output buffer failures, 0 output buffers swapped out
     61 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up

ROUTER-A-1601#

Netstudent · June 2007

Thats because serial 0 is a DTE interface...Notice the output where it states V.35 DTE cable attatched. Try turning the cables around or set clock rate on the other router's serial interface.

ramjet666 · June 2007

Netstudent wrote:

Thats because serial 0 is a DTE interface...Notice the output where it states V.35 DTE cable attatched.

OMG what an idiot, I plugged the cable in the wrong way round from how I had it in my lab diagram. Thx.... slinks away feeling stupid.....

Netstudent · June 2007

NAH man, thats the beauty of having real gear. Learning little quirks like that is priceless. You may even see a troubleshooting question on the exam with the exact same scenario.

Always check the status of the interface on the other side as well. You probably had a default clock rate of 64K set on the 1603.

kafifi13 · June 2007

I was just checking this out. I can't even have this thing power up long enough to get to log in screen. Now it's just flashing random lights at me.

r_durant · June 2007

I agree with Netstudent 100%...this is what it's all about, troubleshooting these types of issues...I'm sure if you come across a scenario like this again, you're gonna go straight to the cables first

You can't beat hands-on...priceless

Setting clock rate

Comments