English dropdown-ico

Xilinx LogiCore LogiCore PCI v3.0 manual

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58

Go to page of

Similar user manuals

A good user manual

The rules should oblige the seller to give the purchaser an operating instrucion of Xilinx LogiCore LogiCore PCI v3.0, along with an item. The lack of an instruction or false information given to customer shall constitute grounds to apply for a complaint because of nonconformity of goods with the contract. In accordance with the law, a customer can receive an instruction in non-paper form; lately graphic and electronic forms of the manuals, as well as instructional videos have been majorly used. A necessary precondition for this is the unmistakable, legible character of an instruction.

What is an instruction?

The term originates from the Latin word „instructio”, which means organizing. Therefore, in an instruction of Xilinx LogiCore LogiCore PCI v3.0 one could find a process description. An instruction's purpose is to teach, to ease the start-up and an item's use or performance of certain activities. An instruction is a compilation of information about an item/a service, it is a clue.

Unfortunately, only a few customers devote their time to read an instruction of Xilinx LogiCore LogiCore PCI v3.0. A good user manual introduces us to a number of additional functionalities of the purchased item, and also helps us to avoid the formation of most of the defects.

What should a perfect user manual contain?

First and foremost, an user manual of Xilinx LogiCore LogiCore PCI v3.0 should contain:
- informations concerning technical data of Xilinx LogiCore LogiCore PCI v3.0
- name of the manufacturer and a year of construction of the Xilinx LogiCore LogiCore PCI v3.0 item
- rules of operation, control and maintenance of the Xilinx LogiCore LogiCore PCI v3.0 item
- safety signs and mark certificates which confirm compatibility with appropriate standards

Why don't we read the manuals?

Usually it results from the lack of time and certainty about functionalities of purchased items. Unfortunately, networking and start-up of Xilinx LogiCore LogiCore PCI v3.0 alone are not enough. An instruction contains a number of clues concerning respective functionalities, safety rules, maintenance methods (what means should be used), eventual defects of Xilinx LogiCore LogiCore PCI v3.0, and methods of problem resolution. Eventually, when one still can't find the answer to his problems, he will be directed to the Xilinx service. Lately animated manuals and instructional videos are quite popular among customers. These kinds of user manuals are effective; they assure that a customer will familiarize himself with the whole material, and won't skip complicated, technical information of Xilinx LogiCore LogiCore PCI v3.0.

Why one should read the manuals?

It is mostly in the manuals where we will find the details concerning construction and possibility of the Xilinx LogiCore LogiCore PCI v3.0 item, and its use of respective accessory, as well as information concerning all the functions and facilities.

After a successful purchase of an item one should find a moment and get to know with every part of an instruction. Currently the manuals are carefully prearranged and translated, so they could be fully understood by its users. The manuals will serve as an informational aid.

Table of contents for the manual

  • Page 1

    R LogiCORE™ PCI v3.0 Getting Star ted Guide UG157 A ugust 31, 2005 v3.0.151[...]

  • Page 2

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com UG157 August 31, 2005 Xilinx is disclosing this Specification to you solely f or use in the dev elopment of designs to oper ate on Xilinx FPGAs. Except as stated herein, none of the Specification ma y be copied, repr oduced, di stri b uted, repub lished, downloaded, di splay ed, posted, or tr ansm[...]

  • Page 3

    w ww .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 06/24/02 3.0 Initial Xilinx release of corpora te-wide common template set, used for U ser Guides, T utorials, Release Notes, Manuals, a nd ot her lengthy , multiple-chapter documents created by both CMP and ITP . See r elated documents for further information . Descriptions [...]

  • Page 4

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com UG157 August 31, 2005[...]

  • Page 5

    w ww .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Preface: About This Guide Guide Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Co[...]

  • Page 6

    PCI v3.0.151 Ge tting Started Guide UG157 August 31, 2005 www .xilinx.com Chapter 5: Synthesizing a Design Synplicity Synplify . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Verilog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

  • Page 7

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 7 UG157 August 31, 2005 R Pr eface About This Guide The PCI Gettin g Started Guide pr ovides information about the LogiCORE™ Peripher al Component Inter connect (PCI) interface, whic h provides a fully verified, pr e-implemented PCI bus interface available in bo th 32-bit and 64-bit versions. Th[...]

  • Page 8

    8 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Preface: About This Guide R Additional Resour ces For additional information, go to ht tp://support.xilinx.com . The following table lists some of the resour ces you can access from this website. Y ou can also directly access these resour ces using the provided URLs. Con ven[...]

  • Page 9

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 9 UG157 August 31, 2005 Con ventions R Online Document The following conventions ar e used in this document: Italic font V ariables in a syntax statement for which yo u must supply valu es ngdbuild design_name Refer ences to other manuals See the Development System Reference Guide for more informa[...]

  • Page 10

    10 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Preface: About This Guide R[...]

  • Page 11

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 11 UG157 August 31, 2005 R Chapter 1 Getting Started The PCI interface provides a fully verified, pr e-implemented PCI bus interf ace available in both 32-bit and 64-bit versions with support for operation at 33 MHz and 66 MHz. This guide defines the supporte d design flows for both the 32-bit and[...]

  • Page 12

    12 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 1: Getting Star ted R T echnical Support For technical support, visit www .xilinx.com/support . Questions ar e routed to a team of engineers with expertise using the PCI interface. Xilinx provides technical support for use of this pr oduct as described in the PCI Us[...]

  • Page 13

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 13 UG157 August 31, 2005 R Chapter 2 Installing and Licensing the Cor e This chapter provides instructions for installing and obtaining a license for the PCI interface cor e, which you must do befor e using it in your designs . The PCI core is pr ovided under the terms of the Xilinx LogiCORE Site [...]

  • Page 14

    14 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 2: Installing and Licens ing the Core R CORE Generator IP Updates Installer 1. From the CORE Generator main GUI, choos e T ools > Updates Installer to start the Updates Installer . 2. If prompted for a pr oxy host, contact your administrator to determine the pr o[...]

  • Page 15

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 15 UG157 August 31, 2005 Installing the Core R the location of the Xilinx installati on. Note that you may need system administrator privileges to install the update. 6. Confirm the directory structur e in one of the following ways: • For W ind ows: <Xilinx_root_directory>core genipxili[...]

  • Page 16

    16 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 2: Installing and Licens ing the Core R Licensing Options Ev aluation The method for obtaining an evaluation license is dete rmined by the version of the PCI core you choose. • For the PCI32/33 V irtex™ and Spartan™ core , register on the Xilinx IP Evaluation [...]

  • Page 17

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 17 UG157 August 31, 2005 Installing Y our Li cense File R Installing Y our License File After selecting a license option, an email will be sent to you that includes instructions for installing your license file. In addition, information about advanced licens ing options and technical support is pr[...]

  • Page 18

    18 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 2: Installing and Licens ing the Core R[...]

  • Page 19

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 19 UG157 August 31, 2005 R Chapter 3 Family Specific Considerations This chapter provides important design inform ation specific to the PCI interface targeting V irtex and Spartan devices. Design Suppor t Ta b l e 3 - 1 provides a list of supported device and int erface combinations. Each entry in[...]

  • Page 20

    20 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R 2S200-FG456-6C 33 MHz 3.3V 64-bit pcim_lc_33_3_s 2s200fg456_64_33.ucf no guide file 2S200-FG456-6C 66 MHz 3.3V 64-bit pcim_lc_66_3_d 2s200fg456_64_66.ucf 2s200fg456_64_66.ncd 2S100E-FG456-6C 33 MHz 3.3V 64-bit pcim_lc_33_3_s 2s1[...]

  • Page 21

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 21 UG157 August 31, 2005 Design Support R V300E-BG432-6C 66 MHz 3.3V 64-bit pcim_lc_66_3_d v300ebg432_64_66.ucf v300ebg432_64_66.ncd V300E-BG432-6C 33 MHz 3.3V 64-bit pcim_lc_33_3_s v300ebg432_64_33.ucf no guide file V1000-FG680-6C 66 MHz 3.3V 64-bit pcim_lc_66_3_d v1000fg680_64_66.ucf v1000fg680_[...]

  • Page 22

    22 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R 2VP20-FF1 152-6C/I 66 MHz 3.3V 64-bit pcim_lc_66_3_s 2vp20ff1152_64_66.ucf 2vp20ff1152_64_66.ncd 2VP20-FF1 152-5C/I 33 MHz 3.3V 64-bit pcim_lc_33_3_s 2vp20ff1152_64_33.ucf no guide file 2VP30-FF1 152-6C/I 66 MHz 3.3V 64-bit pcim[...]

  • Page 23

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 23 UG157 August 31, 2005 Design Support R 4VSX35-FF668-10C/I global clock 33 MHz 3.3V 64-bit pcim_lc_33_3_g 4vsx35ff668_64_33g.ucf no guide file 4VFX20-FF672-10C/I global clock 33 MHz 3.3V 64-bit pcim_lc_33_3_g 4vfx20ff672_64_33g.ucf no guide file 4VLX25-FF668-10C/I regional clock 33 MHz 3.3V 64-b[...]

  • Page 24

    24 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R 2S50-PQ208-5C 33 MHz 3.3V 32-bit pcim_lc_33_3_s 2s050pq208_32_33.ucf no guide file 2S100-PQ208-5C 33 MHz 5.0V 32-bit pcim_lc_33_5_s 2s100pq208_32_33.ucf no guide file 2S100-PQ208-5C 33 MHz 3.3V 32-bit pcim_lc_33_3_s 2s100pq208_3[...]

  • Page 25

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 25 UG157 August 31, 2005 Design Support R 2S300E-PQ208-6C 33 MHz 3.3V 32-bit pcim_lc_33_3_s 2s300epq208_32_33.ucf no guide file V100E-BG352-6C 33 MHz 3.3V 32-bit pcim_lc_33_3_s v100ebg352_32_33.ucf no guide file V300-BG432-5C 33 MHz 5.0V 32-bit pcim_lc_33_5_s v300bg432_32_33.ucf no guide file V300[...]

  • Page 26

    26 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R 3S1200E-FG400-4C/I 33 MHz 3.3V 32-bit pcim_lc_33_3_s 3s1200efg400_32_33.ucf no guide file V200-FG256-6C 66 MHz 3.3V 32-bit pcim_lc_66_3_d v200fg256_32_66.ucf v200fg256_32_66.ncd V200E-FG256-6C 66 MHz 3.3V 32-bit pcim_lc_66_3_d v[...]

  • Page 27

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 27 UG157 August 31, 2005 Design Support R See the product r elease notes in cluded with the core for a complete directory structur e and file list. 4VSX35-FF668-1 1C/I regional clock 66 MHz 3.3V 32-bit pcim_lc_66_3r 4vsx35ff668_32_33r.ucf no guide file 4VFX20-FF672-1 1C/I regional clock 66 MHz 3.3[...]

  • Page 28

    28 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R Wrapper Files W rapper files contain an instance of the PCI interface and the instances of all I/O elements used by the PCI interface. Each w rapper file is specific to a particular PCI bus signaling environment. The wrapper fil[...]

  • Page 29

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 29 UG157 August 31, 2005 Device Initialization R De vice Initialization Immediately after FPGA configuration, both the PCI inter face and the user application are initialized by the startup mechanism present in all V irtex and Spartan devices. During normal operation, the assertion of RST# on the [...]

  • Page 30

    30 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R Although this technique is not technically co mpliant with the PCI specification due to the extra loading on REQ64# and RST# , the us e of a large series r esistor helps minimize this effe ct. The inverter may be pushed into the[...]

  • Page 31

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 31 UG157 August 31, 2005 Input Delay Buffer s R IOBs of the FPGA device. The us e of these delay buf fers is selected through the implementation specific constraints file Some implementations use alternate delay buf fers, selected via the CFG[248:245] bits in the HDL configuration file. Ta b l e 3[...]

  • Page 32

    32 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R 1. The jitter of the source clock, to determine if it is appropriate for use as an input to a DCM. 2. The DCM configuration, to generate a 200 MHz clock on any appropriate DCM output (CLK FX, CLKDV , and so fort h). 3. The jitte[...]

  • Page 33

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 33 UG157 August 31, 2005 Regional Clock Usage R For designs using regional clocking, the PCI interface and those portions of the user application clocked from the PCI bus clock must completely fit inside the three clock region s accessible to the r egional clock signal. This restriction limits the[...]

  • Page 34

    34 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R Bus Cloc k Usage The bus clock output provided by the in terface is derived fr om the bus clock input, and is distributed using a global clock buffer . The interface itself is fu lly synchr onous to t his clock. In general , the[...]

  • Page 35

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 35 UG157 August 31, 2005 Electrical Compliance R maximum allowed fre quency , and the fr equenc y may change on a cycle-by-cycle basis. Under certain condition s, the PCI core may also apply phase shifts to this clo ck. For these r easons, the user application should not use this clock as an input[...]

  • Page 36

    36 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R Figur e 3-3 shows the small range of supply voltage values wher e V IL or V IH are technically non-compliant. Note that this may occur with any PCI device if the input buffer supply voltage is different from the supply voltage o[...]

  • Page 37

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 37 UG157 August 31, 2005 Generating Bi tstreams R Figur e 3-4 shows one possible low-cos t solution to generate the r equired 3. 0 volt output driver supply . Xilinx recommends the use of the circuit shown in Figure 3-4 , although other approaches using othe r regulators are possible. Vi r t e x -[...]

  • Page 38

    38 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 3: Fa mily Speci fic Considerations R This option is used to intr oduc e additional delay on a global clock net. It is important to note that this additional delay is observable on the CLK output of the PCI interface, which is supplied to the user applica tion. T im[...]

  • Page 39

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 39 UG157 August 31, 2005 R Chapter 4 Functional Simulation This chapter describes how to simulate the ping64 example design with global clocks using the supported functional si mulati on tools. For the PCI 32 i nterface, substitute ping32 for ping64 . If you are using a design with refer ence cloc[...]

  • Page 40

    40 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 4: Functional Sim u latio n R Most of the files listed ar e related to the example design and its testbench. For oth er testbenches, the foll owing subset must be used for proper simulation of the PCI interface: ../source/glbl.v ../../src/xpci/pci_lc_i.v ../../src/x[...]

  • Page 41

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 41 UG157 August 31, 2005 Model T echnolog y ModelSim R 3. Modify the library search path by changing <Xilinx Install Path> to match the Xilinx installation di rectory and then save the f ile. Most of the files listed ar e related to the example design and its testbench. For oth er testbenche[...]

  • Page 42

    42 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 4: Functional Sim u latio n R <Install Path>/vhdl/example/ func_sim 4. Create the simprim and unisim libraries. This step only needs to be done once, the first time you perform a simulation: vlib simprim vcom -93 -work simprim <Xili nx Install Path>/vhdl[...]

  • Page 43

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 43 UG157 August 31, 2005 R Chapter 5 Synthesizing a Design This chapter describes how to synthesize the ping64 example design with global clocks using the supported synthesis tools. For the PCI 32 interface, substi tute ping32 for ping64 . If you are using a design with r eference cl ocks, substit[...]

  • Page 44

    44 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 5: Synthesizing a Design R 4. T o add source files to the new project, click Add. The first file (used by any desig n that instantiates Xili nx primitives) is located in: <Synplicity Install Path>/lib/xilinx 5. Navigate to the virtex.v file; then click Add to [...]

  • Page 45

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 45 UG157 August 31, 2005 Synplicity Synplify R The next files ar e located in: <Install Path>/verilog/src/x pci 6. Navigate to the xpci directory , select the simulation model and the wrapper files (pci_lc_i.v and pcim_lc.v), and click Add to mo ve these files into the Files T o Add list. (C[...]

  • Page 46

    46 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 5: Synthesizing a Design R 8. After adding the three final file s (for a total of six sou r ce file s), click OK to r eturn to the main project window . 9. In the Sour ce Files list, view the list of newly added sour ce files by double-clicking th e flowtest/verilog[...]

  • Page 47

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 47 UG157 August 31, 2005 Synplicity Synplify R 13. On the Device t ab, set the T echnology , Part , Speed, and Package options to r eflect the targeted device (a V300BG432- 6 in this example). Be sure that Disable I/O Insertion is deselected. 14. On the Options/Constraints tab, deselect Symbolic F[...]

  • Page 48

    48 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 5: Synthesizing a Design R VHDL 1. Start Synplify and choose File > New , or us e the new file icon on the toolbar . The New dialog box appears. 2. Under File T ype, select Pr oject File and enter the pr oject name ( flowte st in this example) and synthesis direc[...]

  • Page 49

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 49 UG157 August 31, 2005 Synplicity Synplify R 5. Select the virtex.vhd file; then click Add to mo ve this source file into the Files T o Add list. The next files ar e located in: <Install Path>/vhdl/src/xpci 6. Navigate to the xpci directory , select the simulation model and the wrapper fil[...]

  • Page 50

    50 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 5: Synthesizing a Design R The final set of design files (the user app lication) is located in: <Install Path>/vhdl/example/ source 7. Navigate to the source directory , select the cfg_ping.vhd, pcim_top.vhd, and ping.vhd, then click Add. 8. After adding the t[...]

  • Page 51

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 51 UG157 August 31, 2005 Exemplar Leonar doSpectrum R 12. From the main project window , click Change T arget to display the Options for Implementation dialog box, as shown in Figure 5-17 . 13. On the Device t ab, set the T echnology , Part , Speed, and Package options to r eflect the targeted dev[...]

  • Page 52

    52 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 5: Synthesizing a Design R The end r esult of the synthesis step is an EDIF fi le that is fed into th e Xilinx implementation tools during the implementation step. In practice, the pr ovided script file must be modified to accommodate other des igns. T o provide ins[...]

  • Page 53

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 53 UG157 August 31, 2005 R Chapter 6 Implementing a Design This chapter describes how to implement the ping64 example design with global clocks using the supporte d FPGA implementation tools (included with the ISE Foundation v7.1 Development System). For the PCI 32 interface, substitute ping32 for[...]

  • Page 54

    54 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 6: Implementing a De sign R •T h e par command, as pr ovided in the script, uses a g uide file in exact guide mode. Note that some designs do not require the use of guide files. T o targ et a different device or to use a dif ferent version of the PCI interface, se[...]

  • Page 55

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 55 UG157 August 31, 2005 R Chapter 7 T iming Simulation This chapter describes how to perform timing simulation using the ping64 example design with global cl ocks using the supported timing simulation tool s. For the PCI 32 interfac e, substitute ping32 for ping64 . If you are using a des ign wit[...]

  • Page 56

    56 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 7: Timing Simulation R NC-V erilog processes the simulation files and exits. The testbench prints status messages to the console. After the simulation completes, view the ncverilog.log file to check for erro rs. The Simvision browser may be used to view the simulati[...]

  • Page 57

    PCI v3.0.151 Ge tting Started Guide www .xilinx.com 57 UG157 August 31, 2005 Model T echnolog y ModelSim R cp ../xilinx/pcim_top_routed .sdf . 2. V iew the ping.files file. This file lists the individual sou r ce files required, and is shown below: ./pcim_top_routed.vhd ../source/busrecord.vhd ../source/dumb_arbiter.vhd ../source/dumb_targ32.vhd ..[...]

  • Page 58

    58 www .xilinx.com PCI v3.0.151 Getting Started Guide UG157 August 31, 2005 Chapter 7: Timing Simulation R[...]