# Hardware Update through Digital TV Signals
## 6 Simulation Results  
The Materials and Methods should be described with sufficient details to allow others to replicate and build on the published results. Please note that the publication of your manuscript implicates that you must make all materials, data, computer code, and protocols associated with the publication available to readers. Please disclose at the submission stage any restrictions on the availability of materials or information. New methods and protocols should be described in detail, while well-established methods can be briefly described and appropriately cited. As a proof of concept (PoC), some HDL source code examples were synthesized, whose goal was to use the entire scheme. Four VHDL and Verilog examples were used, which were synthesized for a reference FPGA and then tested and validated employing an EDA tool. The experimental set-up used in this work included a toolset necessary for validating all steps performed by HARD. To synthesize the digital circuits, Quartus II v.11.0, provided by Altera FPGA manufacturer, was used. Such a tool can generate a reprogramming file in several formats, including the chosen one, which was SVF. The advanced stream combiner (ASC) tool, provided by Rohde & Schwarz, was employed to multiplex the content in a TS. The UIT section was added during TS creation, and the SVF's content was split and encapsulated into private sections. Modulation and broadcasting were achieved by using a VHF/UHF modulator (DekTec DTU-215, USB-2 device) with a companion player tool (StreamXpress v.3.10.2, also provided by DeKlec), which transmits signals according to the Integrated Services Digital Broadcasting Terrestrial (ISDB-T) standard [65]. The receiver device used for testing and development was an NXP-STB225 IP, a hybrid DTV-STB platform provided by NXP semiconductors. The mentioned platform runs a version of the Linux operating system on a 300-MHz MIPS processor. Finally, the employed FPGA device was a Nios Stratix EP1S10F780C6 development board, which was developed by Altera and ran at 50 MHz. The proposed validation was based on typical examples to check if the mentioned FPGA device was configured correctly, and the proposed scheme works in a DTV system. The first pre-synthesized example converted to an SVF file (see Section 3) was a simple binary-coded decimal (BCD) light-emitting diode (LED) counter (Ex01.svf). The second one was a BCD to 7-segment decoder (Ex02.svf). The third was an example that wrote a text message on a 16x2 liquid crystal display (LCD) device (Ex03.svf). Finally, the fourth and last one was a 7-segment counter (Ex04.svf). According to the schema described in this work, each core was multiplexed into its respective TS (see Sections 5.1-5.4). The result of this process consisted of four transport stream files carrying and signaling each respective bitstream. The TS example files were generated according to the ISDB-T standard [65], similar to what is performed in terrestrial DVB. For this process, the said MPEG TS generator and packet manipulator tool were employed. The bit rate used to multiplex each transport stream was 1.57 Mbps. The first set of experiments was performed to establish the best section repetition rate used in HARD. Regarding that, eight transport streams carrying and signaling the Ex01.svf hardware core were generated. Thus, for the first example, the repetition rate used was 500 ms. Next, repetition rates of 750 ms, 1000 ms, 1250 ms, 1500 ms, 1750 ms, and 2000 ms were successively tested (see Table 8). According to Table 8, the results using a rate of 500 ms (Ex01_500 ms.ts) presented the lowest performance during the remounting process with private sections. With this specific rate, the remounting system had a greater discarding of sections than lower rates, which happens when the remounting system captures a smaller number of sections in each repetition cycle. When using 750 ms (Ex01_750 ms.ts), there was an improvement in the remounting performance due to reduced discarding of sections compared with the 500-ms repetition rate.