A660-2007-T306#L7R503A扫描仪模块
A660-2007-T306#L7R503A扫描仪模块
A660-2007-T306#L7R503A扫描仪模块
一、主板的模块结构功能
主板主要由CPU芯片组(Chipset)、高速缓存(Cache)、系统总线槽、RAM(内
存)、系统BIOS(基本输入输出管理系统)及输入输出设备接口等组成。主板的
主要功能是支撑和协调主板上的各个功能部件运行工作,为它们提供信息通
路和数据通道。计算机的主要电路和核心部件都集成在主板上。
按其电路功能分为以下几大模块。
1.CPU模块
CPU模块包括CPU芯片、CPU插座和风扇。CPU的类型不同,CPU的插座
也不一样。
2.内存模块
内存模块包括内存插槽和内存条。
内存插槽是连接和放置内存条的地方,它决定着所安装的内存条类型,目
前的形式有168线槽(DIMM槽)和184线槽(RIMM槽)。
3.芯片组(Chipset)
芯片组称为控制芯片组(Chipset),由一片或多片超大规模集成电路芯片构
成。主要包括以下功能电路。
1)总线控制器
其主要功能是执行CPU的命令,根据CPU的状态信号译码出各种控制命令,
并代替CPU去下达命令,送往各功能电路
2)计时/计数器
计时/计数器是计算机电路中的辅助时钟发生器,用硬件电路实现分频并产
生其他时钟脉冲,供给除CPU以外的其他电路使用,它产生的时钟主要有三
种用途:一是系统时钟计时(System Timer CLK),作为系统计时及时间的处
理;二是内存刷新时钟(DR?MRefresh CLK),对DRAM进行数据刷新;二是13
喇叭声音时钟(SPEAK CLK),产生各种声频的时钟,用来控制扬声器发声
3)中断控制器
控制各种硬件向CPU申请中断的优先权.
合闸电源模块\SCHNEIDER ELECTRIC\C2891-A F2 5
UL-722Q-R1A-B025 1
SGM7F-02A7A41 1
FX3S-30MT/DSS 1
GD350A-055G/075P-4 55/75 kW
EC-TX509C 两套
MN-S4-FCS-500-A 100
E32GAC10000M5H9XXX-02S13414000 1
A9C20842 1
A9D32616 3
A9A26927 5
A9C22512 7
A9D55604 2
A9D37632 4
F1S1250A 1250A 1
霍尼FE USI 0002 CC V1.0 1
ZZA08-UL31Q157K 30pcs
18779-HXP-1-1K-2 10pcs
18779-HXP-1-15K-5 10pcs
型号: LMT200.E2.S6.R2.B1.D2.L2.H1.SEH--M5 数量2台。
6ES7522-5HH00-0AB0 2
6ES7155-6AU00-0BN0 1
ECSEE012C4B 1
MDX60A0150-503-4-00 1
EVF8218-E 1
E82EV222_4C000 1
5.561.013 1
FF300R17KE4 6
HE-CPU-200 1
AI4RD 1
CPU30AT 1
ERAD280-4S 3
MFS500A/1600V 1
APF5.820.112C-A 1
10-58SN-1552-1024 1
11-58HN-8755-4096 4
AC70-T3-011G/015P 11KW/15KW
MD480T11GB 1
2410ML-05W-B79 6
4715VL-05W-B76 4
614 N/2HHR 2
PMD240PQB1-A 2
RHA 400D4.123B-2DT 2
FE6070C 1
TGC65-ET DC24V 16W 3
FTLF8529P3BCV 10
ATV1200C-D5000049 1
SFP-GE-LX-SM1310-D 10
5.561.028 1
APF5.820.111D-A 1
GW-3000 5
GW-5000 3
JE-2000A 6
HD-M-A44620 RS485 1
1.B&R2100 5PC2101 5AP1120156B000 数量1pc
2.B&R: 8V1090.00-2 数量 1 pc.
500PSM03 8
A5E00314745 1
6055-PROF-00 1个
FX-8AD 三菱模块 (1个)
FX-16EX/ES 三菱模块 (1个)
FX-16EY/ES 三菱模块 (1个)
GT2107-WTBD-N 三菱触摸屏 (1个)
1 Servomotor Omron R88M-K75030H-S2 120V 4.1A 0.75kW 3000r/min 1 piece
2 Servo drive Omron R88D-KND-KN08H-EST 1 pc.
3 Uninterruptible power supply PW9130i3000R-XL2U 3000VA IEC320C13 (computer) 8 3.5 min (3000VA) Eaton 1
4 Temperature regulator Delta DTB4848VR b/s 110...240V 2 pcs
软启动器RVS-DN 310400-230-0-9-S 1
TSX3708001 1台
FX5-32ET/DSS 1
6SL3040-1LA01-0AA0
3RW3047-1BB14 5
HF-KP010M5B-S1 2
1769-SDN 面价13065 1个
DP/RS232/RS422/RS485 Gateway
Model: XPS-E
Brand: Comsoft
F24-10D
Brand: Telecrane
各1 孟加拉
6ES7158-3AD10-0XA0 2
6GK1503-2CA00 3
6SL3040-0PA00-0AA1 1
科尔摩根S406AM-CA 00800231022 1
MM-R-001B 1
Honeywell 135-105QAF-J01 1
FR-E740-2.2K-CHT 2
FR-E740-0.75K-CHT 2
CM200DU-24F 12
8LSA26.D9060S000-3 2
8LSA46.DB060S200-3 2
8EI2X2HWDS0.L700-1 2
8EI2X2HWTS0.L700-1 2
8EI017HWDS0.0300-1 2
8EI8X8HWTS0.0700-1 2
8LSAA2.D9045S000-3 2
L404V-1053 10pcs
10-AKB-20 8
Numatics 122BA400M011B61 10
Numatics 239-1519 Profibus 1
Numatics 239-1174
762CNA-BT ST.AA
BYT261PIV-400
STTH120R04TV1
WP-5238-CE7 1PCS (要未税价)
MGFAS2-DSM-DSC-B/ECR 1
KL9181 6个
LJS-E7312 1
8I74T401500.010-1数量1
XBT-N401 1
RE06M35W2V1XW20 1
GT2107-WTBD 1
SensorRenishawTS27R 1个
FX3N-64MR-001 1个
MSP40-00280TCZ9MRHHE3A 1个
MD480T45G 1
MD480T200G 1
MD480T90G 1
ZFV-CA45 1个
OMRON 3F88L-130 1
800FMF4 10
MD500ET75G-BS 1
A4K-M564 1
Gear selector SHIFT SELECT 29536934 Allison 1
IBS 24 BK-1/0-T 订单号:2759980 11件
IBS 24 DO/LC 订单号:2784667 数量191
MRT1000
Brand: MITECH 1 孟加拉
1734-IE2C 5 面价3142
1SAM451000R1016 2
1SBL177001R1310 2
1SBL237001R1300 2
ACS580-01-046A-4 5300现货全新未税
ACS580-01-062A-4 1
ATS22C11Q 2
ATS22D75Q 2
3BDH000530R1 2
PM803F
3BDH000022R1 4
EI813F
3BDH000032R1 2
FI830F
3BDH000030R1 2
FI810F
3BDM000199R1 2
SB808F
3BDH000013R1 2
SA811F
137-6AA01-0BA0 1
ACS880-07-0650A-3 1
ACS580-04-880A-4 1
GPS2BHAR 12个 GE
CL45F300M 12个 GE
A06B-0243-B101 1
A13B-0199-B062 1
5069-OB16F 面价7417 1个
3BHE045463R0001数量2
UA D155 40111数量5
1746-A10 14097 2
1746-A13 19526 1
231-7PF22-0XA0 1个
650-8EK80-1AA0
650-8DK80-1AA0
650-8BK60-1AA0
650-8PH00-1AA0
650-8AK70-1AA0 各一..
RPBA-01/PROFIBUS-OP 1
7RW8020-5EB90-1DC0 L0A 2
3RB2163-4GC2 10
3VL5763-1DC36-0AA0 1
3VF3111-5DQ71-0AA0 6
3VA1163-5ED36-0AA0 1
TCSESM083F2CUOM 1
ILM1001P11A0000 1pc
1SVR011708R0400 1
CC-E/I
ACH550-UH-059A-4 1个
ACS580-01-017A-4 1
800FM-F4 10 面价33
电源模块 SX控制器电源-SE5009
模拟量输入模块 2W/4W-SS4303T01
模拟量输入模块 SE4003S2B4
数字量输入模块 SE4301T02
数字量输入模块 SE4301T07 ISOL
数字量输入模块 SE4001S2T2B4
数字量输入模块 LS DI 24-SS4301T02
数字量输出模块 SE4302T51
数字量输出模块 SE4302T01 HIGH-SIDE
数字量输出模块 SE4302T02 ISOL
数字量输出模块 LS DO 24 DTA-SS4302T01
数字量输出模块 LS DO 24 ETA-SS4302T02
数字量输出模块 SE4002S1T2B5
模拟量输入模块 4-20mA 2W/4W-SE4303T01
模拟量输入模块 mV-SE4303T52
模拟量输入模块 4-20mA RTD-SE4303T03
模拟量输出模块 SE4005S2B1
模拟量输出模块 SE4304T01
模拟量输出模块 SE4005S2B4
电源模块 VE5129
CPU SX控制器-SE3007
电源模块 VE5133
模拟量输入模块 4-20mA RTD-SS4303T03
模拟量输入模块 SE4003S2B1
模拟量输入模块 SS4303T52
模拟量输入模块 SE4003S6B1
通讯模块 CIOC2-SE6504
底板 LS AI插槽-SS4303T03 RTD
底板 SE4050E0C0
底板 DI插槽-SE4301T02 干点
底板 AI插槽-SE4303T03 RTD
底板 底板地址插头-SE4602
底板 AI插槽-SE4303T01 HART
底板 12槽底板-SE4601T07
底板 DO插槽-SE4302T01 HIGH-SIDE
底板 DO插槽-SE4302T02 ISOLATED
底板 LS AI插槽-SS4303T01 HART
底板 SIS底板终端-SS4604T04
底板 LS DO插槽-SS4302T01 DTA
底板 SIS底板地址插头-SS4602
底板 LS DO插槽-SS4302T02 ETA
底板 12槽SIS底板-SS4601T07
底板 LS DI插槽-SS4301T02 干点
底板 底板终端-SE4604T04
底板 SE4050E1C0
6FC5111-0CA05-0AA0 3
6EP1935-6ME01 1
6AG4104-4EA01-0XX3 数量1
ABB KSD302-16A-75NC - 6个
ABB GTH4048ZA2 - 6个
ABB SACE Tmax T4L250 PR221DS1SDA054506R1 - 1个
800FM-F4 10 面价33
ATV320U40N4B
ATV320U30N4C
ATV320U30N4B
ATV320U75N4B
ATV320U06N4B 各1
P14121SA6M0B88L 2
6SL3121-2TE21-8AA3 1
ABB 500PSM03 1
6ES7511-1AK00-0AB0 1
6ES7534-7QE00-0AB0 2
6ES7131-6FD00-0BB1 2
6ES7132-6FD00-0BB1 2
6ES7134-6HD00-0BA1 1
VW3E2094R350 1
6FX2001-5JE24-2DC0 1
3VL9400-1UG01 2
1TGE120071R1000 3
3HAC025562-001 1
3HAC025981-001 1
140DDO84300 面价5848 数量2
TM3AQ4G 1
6ES7655-5DX40-2AA0 6
6ES7652-0XX00-1XD2 1
6AG1124-0QC02-4AX1 1
3AUA0000097468 1台
艾默生MegaVert-G4150-06/06B 成品板---MFC075B0U1 2
MSK071E-0300-NN-M1-UG2-NNNN
R911315269 1
VIA1001C31F0022 1
iSH100/30025/0/1/00/0/10/01/00
700DC-P1200Z1
ABB的ACS880-07-0650A-7 1
BMXCPS4002H 1
6ES7972-5AA10-0AB0 1
6ES7972-5AA51-0AB0 1
6ES7972-5AA80-0XA0 1
6ES7903-1AH40-0AB0 1
6ES7972-5AB00-0XA0 2
5.561.013 1
HD9MS-A069-0050-400000 1
ATV1200C-D5000049
5.561.028 1
138-4FA04-0AB0 3
2090-CSBM1DF-14AF15 9545 1
CM-IWM.11,物料号1SVR470670R1100,数量:12个
6SN1111-0AA00-1EA0 1
2711P-RP2X 无面价 1个
6FX5002-2DC10-1DA0 2
6GK1503-2CA01 3
210-1PE16-1UL1 1
953-8LM32-0AA0 1
6DD1661-0AE1 1
1756-L73S 1 面价203041
OT315ERRR6TZ ABB 1
3BSC610037R1 5
SK-R1-MCB1-PF753 1 7576
SK-R1-CP1-C770D740 1 50508
SK-R1-PWRS1-CD-F8 5 5624
SK-R1-MCB1-PF755 PN-382035 5 12540
700S/20-VB00299 1
PF755/PN-73899 5
PF755/PN-43286 2
PF755/PN-132647 2
其余没查到面价
6314HR 5
4656Z 5
6DD1640-0AH0 2个
VX4X6000110 1
IC695ALG608 2
GCR_NS630_1600 2
SU203MR-K2 abb 6pcs
IC200PBI001-MH 1
C1E15ENS3
CE15ENS3
K1AE56BN0
H2105B
H2108B
CS60F-C1/60/CE/X
数量1
C79451-A3260-A16 2
6DS3900-8AD 2
440N-G02099 新面价:5188 3
ACH550-UH-059A4 1
6SE6430-2UD42-0GB0 1
7SJ6865-5CW90 数量4
6ES7135-0HF01-0XB0 数量1
6ES7416-3XL00-0AB0 CP416-3 数量1
3RP1505-1BP30 数量5
8BK30中压开关装置序号:20030163柜体内:3TL6133-3BM4-Z Ith 450A接触器小车,控制电压220VDC 数量1
5SX52/C6 220VDC 务必带5SX9100 HS辅助接点 数量5
6FX5002-2DC10-2AA0 数量1
CM10/0S0S0E0/STD 2
BMXAM00210
BMXAMO0210
BMXP341000
HMIDT351
6GK1161-3AA01
6ES7 368-3BC51-0AA0 2
6ES7197-1LA04-0XA0
6ES7972-0DA00-0AA0
4WE10J10/LG24NZ5L/B10 1
MODEL:HED 40 A16/100 Z15L24S 2
F1S1250A 1250A 1
STS22D55N4X 2
STS22C13N4X 1
马达Z-SGMAS-01ACABC
马达Y-SGMAS-01ACA21
马达类WAF-Z-SGMAS-01ACAJ161
各1
ABB变频器:ACS800-104-0580-7+E205 1
AVTRON PAPER MACHINE D3138 DIGITAL SPEED PERCENT MODULE PC CIRCUIT BOARD 58571
Avtron A10442 Memory Adder Rev. B C12172 849539 USED
AVTRON K661C14326 BLESS TACHOMETER FREQUENCY VOLTAGE CONVERTER 240PPR 28498
AVTRON A14702 *NEW*
AVTRON K661C14326 FREQUENCY TO VOLTAGE CONVERTER QUANTITY!!!
AVTRON A10459 CALIBRATION BOARD
AVTRON A11021 DECODER MODULE
Avtron A10842 Latched Inpu/Ouput Board Rev G USED
Avtron A10459 Calibration Board Rev F NEW-NO BOX
Pair Vintage Avtron Choke Coil Transformers
AVTRON A11021 DECODER BOARD
AVTRON A10459 CALIBRATION BOARD
AVTRON B 3021 B3021 READOUT ELECTRONIC CIRCUIT MODULE CARD PC BOARD D-2702 58572
AVTRON D2344 CIRCUIT BOARD PLC MODULE CARD 56207
Avtron HS35A Encoder
AVTRON C-3119 SUPPRESSION MODULE FOR T361AK DIGITAL SPEED AND DRAW 54609
AVTRON MODEL 420 *USED*
Avtron A14702 Amplifier Card Used
AVTRON A10842 INPUT/OUTPUT MODULE
Avtron A11021 Decoder Board Rev H USED
AVTRON MODEL M727 STYLE 1D PPR 240 OPTION UC PULSE TACHOMETER
AVTRON A11514 MEMORY EXPANDER
AVTRON A11514 MEMORY EXPANDER
Avtron A11514 Memory Expander Board Rev B USED
Avtron Set Point Assembly K521, #8788
Avtron Speed Meter, # K653, WARRANTY
NEW AVTRON M628A PULSE GENERATOR W/1Q-240 OPTION
AVTRON A10442 MEMORY ADDER
AVTRON A14787-1 DISPLAY LCD BOARD CARD
AVTRON AMPLIFIER CARD A14702 GOOD USED TAKEOUT
AVTRON K661 *USED*
AVTRON PULSE GENERATOR MODEL K740
AVTRON BLESS TACHOMETER, MODEL: K661
AVTRON A10442 MEMORY ADDER
AVTRON A10841A MICROPROCESSOR MODULE
AVTRON BLESS TACHO METER K661 *NICE*
AVTRON, K662C17201, BLESS TACHOMETER, USED
AVTRON pulse generator model K740 tachometer
AVTRON B29523 NETMAX ETHERNET COMMUNICATION COPROCESSOR
AVTRON M284L SMARTACH ENCODER
Avtron ADDvantage-32 Technical Manual
Avtron A16625 Rev. H Control Board
AVTRON MFG DC Power Supply Assembly Unit #C16238
Avtron Neutral Grounding Resister Lightning Suppression
AVTRON ANG-24-1 NSFP ANG241
AVTRON ADDVANTAGE-32 DC DRIVE CONTROLLER DC0180-4DL0-B
Avtron 1 HP 1750/2300 RPM Motor w/ Pulse Generator & 50:1 Ratio Gear Reducer
Avtron 2 HP 1750/2300 RPM Motor w/ Pulse Generator
Avtron Card Switch D704T170 Aircraft landing gear part
Avtron, 90 KVA, 400 Hz, Aircraft GPU Load Bank
Enlarge
Avtron K490
Avtron PC Board Microprocessor W/Sub a20136 630264 NIB
Avtron 630103 PC Board
Avtron K490 Load Bank
AVTRON K927B/IR-1200 PULSE GENERATOR/TACHOMETER ***RFB***
Returns: Accepted within 60 days
AVTRON M925 5.0VDC,180mA PULSE GENERATOR
AVTRON C12389 K660A FREQ TO VOLT CONVERTER ***NNB***
Returns: Accepted within 60 days
M685T-51-HC1-HC1 Avtron Incremental Encoder
1 NIB AVTRON M285 M284 ENCODER / PULSE GENERATOR
AVTRON BRIDGE INTERFACE MODULE A19273-1 REV. M A192731
M485-51-HP1-HP1 Avtron Incremental Encoder
AVTRON PULSE GENERATOR M628A
Avtron M938 Pulse Generator
AVTRON DC0030-4BN2-C/D24386-2 DC DRIVE CONTROLLER ****XLNT****
Returns: Accepted within 60 days
Avtron Rotary Pulse Generator M68548-LP1-LP1 M685 M484
1 NIB AVTRON M484L ROTARY PULSE GENERATOR 12 - 15 VOLTAGE
AVTRON K652 RATE INDICATOR ***XLNT***
Returns: Accepted within 60 days
AVTRON M3 1S2R1024A033 INCREMENTAL ENCODER ***NIB***
Returns: Accepted within 60 days
1 NIB AVTRON M85 THIN LINE ENCODER 5-15 VOLTS 240 PPR
AVTRON CONVERTER MODULE C12389
Avtron Readout Assembly A10995 Rev. H C12616
AVTRON 1WF2GXW920 MODEL M85 TWO PIECE MODULAR INCREMENTAL ENCODER C FACE 52906
AVTRON A11075 REVISION REV H COMPUTER MOTHERBOARD MAINBOARD CHASSIS RACK BOARD
Avtron K885 Display Assembly
AVTRON INCREMENTAL ENCODER M4 3S1LX48-F008
Avtron Incremental Encoder w/Accessory Cover model# HS25A #10123DC
AVTRON M56 1BT1DXP000 PULSE GENERATOR 5-24V 50MA LOT OF FOUR BRAND NEW
Avtron AC Hipot Tester Model K126 Rack Mount
AVTRON PULSE GENERATOR # 43-4S241024P000 -NEW-
AVTRON PULSE TACHOMETER K670
AVTRON K662 BLESS TACHOMETER K662C17201 115VAC CONVERTER MODULE 26208
AVTRON M484
AVTRON PULSE GENERATOR M627A
AVTRON ASY. A14142 REV. K
NEW AVTRON M56 THIN LINE ENCODER MAGNETIC MODULAR 1BE2EX9000 5-15V 50MA
Avtron M627A Pulse Generator
AVTRON M5 1S1D1024T000 REV. B NEW PULSE GENERATOR M51S1D1024T000
AVTRON A10459 CALIBRATION BOARD
AVTRON, MOD#T535 TRANSMITTER UNIT, 240 PULSE PER REVOLUTION, FOR HAZ LOCATION
AVTRON M185 PULSE GENERATOR 12-15VDC ***XLNT***
Returns: Accepted within 60 days
Avtron SmartTach Encoder New M284L
AVTRON PULSE GENERATOR M727
AVTRON PULSE GENERATOR MODEL # M737A
AVTRON PULSE GENERATOR M727A STYLE ID
AVTRON PULSE GENERATOR, MODEL: M737A, STYLE: 1D, PPR: 240
AVTRON A11021 DECODER MODULE
AVTRON PULSE GENERATOR M737A, STYLE 1D
Avtron A14702 Amplifier Card New
Avtron M628A Tachometer / Encoder
Avtron PDC-5 Shunt Isolator Assembly PDC5 A19029
AVTRON A10405 REV.F AMPLIFIER CARD MODULE PCB CIRCUIT BOARD ASSY ASSEMBLY
AVTRON A10842 REV.E LATCHED LATCH INPUT OUTPUT BOARD MODULE CARD 27032
Avtron M785 Tachometer Encoder
AVTRON A11021 REV.H DECODER BOARD MODULE K880 CARD
AVTRON C16238 DC POWER SUPPLY IN: 115V 60HZ 5A ***NNB***
Returns: Accepted within 60 days
AVTRON PLUS TACHOMETER M727A 240PPR 12-15VDC 50MA
AVTRON A10442 MEMORY ADDER
AVTRON A10841A MICROPROCESSOR MODULE
AVTRON A11514 MEMORY EXPANDER MODULE
AVTRON CIRCUIT BOARD A14813 REV. H A14848 REV.C A14783 REV.C 630103 630099 63010
AVTRON A10459 REV.F CALIBRATION BOARD MODULE CARD PCB 22650
Avtron A11021 PC Board
Avtron M727A 1D-240-U Encoder Tachometer
Avtron M737A Tachometer
AVTRON D19221 153 COMPACT REMOTE ***XLNT***
Returns: Accepted within 60 days
AVTRON A10459 REV.G CALIBRATION BOARD MODULE ACRD PBC 22832
Avtron 1R-240 Incremental Encoder
Avtron A10842 PC Board
Avtron A10459 PC Board
AVTRON M460 PULSE GENERATOR
AVTRON CIRCUIT BOARD CARD A11021 REV. J DECODER MODULE
AVTRON 6300032 A111514 6300 REV.A MOMORY EXPANDER MODULE 22834
New! Avtron M460 Pulse Generator 1D C-Face 240 PPR 56C
Avtron M460 Pulse Generator
AVTRON M5 1S1D1024T000 REV. B REMANUFACTURED PULSE GENERATOR M51S1D1024T000
Avtron Pulse Generator M727A Parts Only
AVTRON 630031 A11514 REV B MEMORY EXPANDER MODULE BOARD CARD SUB-ASSY ASSEMBLY
AVTRON A10842 REV.G LATCHED IN/OUTPUT BOARD MODULE CARD 22656
Avtron C16237 PowerSupply
AVTRON K662 BLESS TACHOMETER K662C17201 115VAC CONVERTER MODULE 26208
Avtron A10405 PC Board
AVTRON MODEL K740 A PORTABLE PULSE GENERATOR 80PPR TACHOMETER ENCODER HANDHELD
Avtron Manufacturing Inc Brushless Tachometer K661
Avtron A10442 PC Board Memory Adder
Avtron A9109 Setpoint Assembly
Avtron A1479 PC Board
New Avtron Setpoint Assembly A9097 AVTA9097 C10851
Avtron A10841A PC Board
AVTRON A10841A 630007 630031 MICROPROCESSOR M-P CPU ASSY BOARD CARD 22836
Avtron Pulse Tachometer / Encoder M737A 2D 240 BC
Tachymètre
AVTRON A10442 REV.B MEMORY ADDER BOARD MODULE CARD PCB ASSY ASSEMBLY
Avtron K661 Brushless Tachometer
AVTRON CIRCUIT BOARD CARD A10442 REV. C