Jean-Luc Aufranc (CNXSoft), Author at CNX Software - Embedded Systems News

March 2, 2016September 4, 2017 by Jean-Luc Aufranc (CNXSoft) - 25 Comments

Banana Pi BPI-M2+ is another Compact Allwinner H3 Development Board

Allwinner H3 processor has become popular on hobbyist boards thanks to several Orange Pi board, especially Orange Pi PC and Orange Pi One due to their ultra-low prices, respectively $15 and $10. Olimex is also involved with their H3-OLinuXino-NANO board, and now at least one more company is about to release another Allwinner H3 board with SinoVoip’s Banana BPI-M2+. Banana BPI-M2 Plus specifications: SoC – Allwinner H3 quad core Cortex A7 @ 1.2 GHz with an ARM Mali-400MP2 GPU up to 600 MHz System Memory – 1GB DDR3 Storage – micro SD card slot up to 64GB, optional 8GB eMMC flash Video & Audio Output – HDMI with CEC support Connectivity – Gigabit Ethernet, optional 802.11 b/g/n WiFi (AP6212). More options: AP6181, AP6335 USB – 2x USB 2.0 host ports, 1x micro USB OTG port Camera – CSI Interface Expansions – 40-pin Raspberry Pi compatible header Debugging – 3-pin UART […]

March 2, 2016March 2, 2016 by Jean-Luc Aufranc (CNXSoft) - 1 Comment

Arduino Tian Board Combines Atmel D21 MCU, Atheros AR9342 WiSoC, and CSR8510 Bluetooth 4.0 SoC

Arduino Tian is an update of Arduino Yun board, mainly replacing Atmel ATMega32u4 8-bit MCU and Atheros AR9331 WiSoC with more recent Atmel SAMD21 32-bit Cortex M0 MCU and Atheros AR9342 WiSoC with support for dual band 802.11 b/g/n WiFi, as well as CSR8510 Bluetooth 4.0 SoC. Arduino Tian specifications: MCU part MCU – Atmel SAMD21G18 ARM Cortex-M0 MCU @ 48 MHz with 256KB flash and 32KB SRAM Digital I/O Pins – 20x GPIOs with 12x PWM and UART Analog Input Pins – 6x 12-bit ADC channels Analog Output Pins – 1x 10-bit DAC DC Current per I/0 – 7mA Operating Voltage – 3.3V “Linux” SoC part SoC – Atheros AR9342 MIPS74Kc processor @ 535 MHz System Memory 64MB DDR2 Storage – 16 MB Flash for firmware, 4 GB eMMC Flash for data Connectivity – 10/100M Ethernet, dual band 802.11n 2×2 2.4/5 GHz WiFi, Bluetooth 4.0 + EDR (CSR8510) USB […]

March 2, 2016March 2, 2016 by Jean-Luc Aufranc (CNXSoft) - 73 Comments

Wintel Pro CX-W8 Cherry Trail mini PC Sells for $85

I reviewed Wintel W8 mini PC powered by an Intel Atom Z3735F last year, although since the model could dual boot Windows 8.1 and Android 4.4 I mostly focused my review on the Android part. There’s now an upgraded model running Windows 10 only, based on Intel Atom x5-Z8300 quad core Cherry Trail processor, and very much the same interfaces except one of the USB 2.0 ports has been upgraded to USB 3.0. Wintel Pro CX-W8 has very similar same specifications to other Cherry Trail mini PCs available on the market: SoC – Intel Atom x5-Z8300 “Cherry Trail” quad core processor @ 1.44 GHz (Bust freq: 1.84 GHz) with Intel Gen8 HD graphics (2W SDP) System Memory – 2 GB Storage – 32 GB eMMC + micro SD slot Video Output – HDMI Audio I/O – HDMI, 3.5mm microphone jack Connectivity – 10/100M Ethernet, 802.11 b/g/n Wi-Fi, and Bluetooth 4.0 […]

March 1, 2016May 29, 2017 by Jean-Luc Aufranc (CNXSoft) - 71 Comments

Raspberry Pi 3, ODROID-C2 and Pine A64+ Development Boards Comparison

Raspberry Pi 3 and hardkernel ODROID-C2 launched the same day, and together with Pine A64/A64+, are the only ultra low cost (<$40) 64-bit ARM development boards available or soon-to-be available, so I’ve decided to make a comparison of the three boards the same way I did with ~$10 boards with a Raspberry Pi Zero, C.H.I.P, and Orange Pi One comparison. I’ve used features of Pine A64+ instead of Pine A64 since features and price are closer to the other two boards. Text highlighted in green means a board is clearly better than the other two for a given features, while a red highlight means it’s the weakest of the three. Raspberry Pi 3 ODROID-C2 Pine A64 Plus Processor Broadcom BCM2837 quad core Cortex A53 processor @ 1.2 GHz(4x ~2760 DMIPS) Amlogic S905 quad core Cortex A53 processor @ 2.0 GHz(4x ~4600 DMIPS) Allwinner A64 quad core Cortex A53 processor @ […]

March 1, 2016 by Jean-Luc Aufranc (CNXSoft) - 4 Comments

GNU Complexity Command Line Tool Measures Complexity of C Code

GNU complexity is a command line tool that computes a complexity measure of C source code, similar to pmccabe, but with a different method of calculating results with short functions scoring lower than pmccabe and highly nested functionality can score considerably higher. It can be useful to locate suspicious areas in unfamiliar code, get an idea of the efforts required to either understand the code or test it, or self-assess your own code. Bruce Korb, the maintainer, has just released version 1.5 with some bug fixes, so I’ve given it a quick try. We’ll need to get the code, build and install it first:

wget ftp://ftp.gnu.org/gnu/complexity/complexity-1.5.tar.gz
tar xvf complexity-1.5.tar.gz
cd complexity-1.5
./configure
make -j8
sudo make install

wget ftp://ftp.gnu.org/gnu/complexity/complexity-1.5.tar.gz

tar xvf complexity-1.5.tar.gz

cd complexity-1.5

./configure

make -j8

sudo make install

The user’s manual provides some insights and an example, which I’ve used against a directory in Linux source code:

cd ~/edev/linux/arch/arm64/kernel
complexity --histogram --score --thresh=3 `ls *.c`
procedure fpsimd_pm_init in fpsimd.c ended before final close bracket
procedure fpsimd_hotplug_init in fpsimd.c ended before final close bracket
Complexity Scores
Score | ln-ct | nc-lns| file-name(line): proc-name
    3      28      17   perf_callchain.c(111): perf_callchain_user
    3      20      18   insn.c(337): aarch64_insn_decode_immediate
    3      21      19   io.c(27): __memcpy_fromio
    3      21      19   io.c(56): __memcpy_toio
    3      30      19   cpufeature.c(860): verify_local_cpu_capabilities
    3      21      20   module.c(74): reloc_data
    3      24      20   setup.c(199): request_standard_resources
    3      27      20   alternative.c(89): __apply_alternatives
    3      29      20   cpu_ops.c(53): cpu_read_enable_method
    3      29      24   insn.c(362): aarch64_insn_encode_immediate
    3      31      24   ptrace.c(76): ptrace_hbptriggered
    3      54      24   kgdb.c(159): kgdb_arch_handle_exception
    3      28      25   armv8_deprecated.c(145): update_insn_emulation_mode
    3      32      25   debug-monitors.c(334): aarch32_break_handler
    3      35      26   smp.c(413): acpi_map_gic_cpu_interface
    3      42      26   process.c(249): copy_thread
    3      58      27   perf_event.c(572): armv8pmu_handle_irq
    3      32      28   hw_breakpoint.c(544): toggle_bp_registers
    3      34      28   insn.c(1019): aarch64_insn_gen_data3
    3      34      29   insn.c(519): aarch64_insn_gen_comp_branch_imm
    3      56      29   setup.c(121): smp_build_mpidr_hash
    3      35      30   insn.c(397): aarch64_insn_encode_register
    3      42      31   signal.c(167): setup_sigframe
    3      37      33   hw_breakpoint.c(349): arch_bp_generic_fields
    3      49      34   setup.c(232): relocate_initrd
    3      41      35   insn.c(708): aarch64_insn_gen_add_sub_imm
    3      63      38   setup.c(292): setup_arch
    3     109      57   cpufeature.c(469): update_cpu_features
    4      46      26   smp.c(477): of_parse_and_init_cpus
    4      38      31   traps.c(335): call_undef_hook
    4      36      32   insn.c(924): aarch64_insn_gen_data1
    4      49      33   armv8_deprecated.c(464): cp15barrier_handler
    4      71      34   stacktrace.c(41): unwind_frame
    4      42      35   ptrace.c(437): hw_break_set
    4      42      37   insn.c(968): aarch64_insn_gen_data2
    4      49      37   smp.c(708): handle_IPI
    4      58      37   hw_breakpoint.c(231): hw_breakpoint_control
    4      47      40   insn.c(757): aarch64_insn_gen_bitfield
    4      54      44   ptrace.c(376): hw_break_get
    4      60      44   armv8_deprecated.c(378): swp_handler
    5      28      27   hw_breakpoint.c(198): hw_breakpoint_slot_setup
    5      45      35   ptrace.c(672): compat_gpr_get
    5      50      36   hw_breakpoint.c(764): reinstall_suspended_bps
    5      59      37   hw_breakpoint.c(476): arch_validate_hwbkpt_settings
    5      48      42   insn.c(811): aarch64_insn_gen_movewide
    5      49      42   insn.c(868): aarch64_insn_gen_add_sub_shifted_reg
    5      60      44   psci.c(36): cpu_psci_cpu_init_idle
    5      49      46   insn.c(277): aarch64_get_imm_shift_mask
    5      95      89   asm-offsets.c(34): main
    6      34      32   cpufeature.c(792): __raw_read_system_reg
    6      67      37   signal.c(332): do_signal
    6      43      39   topology.c(50): parse_core
    6      54      41   ptrace.c(724): compat_gpr_set
    6      74      44   traps.c(147): dump_backtrace
    6      55      49   insn.c(646): aarch64_insn_gen_load_store_pair
    6      76      49   hw_breakpoint.c(393): arch_build_bp_info
    6      71      52   hw_breakpoint.c(584): breakpoint_handler
    6      61      54   insn.c(1062): aarch64_insn_gen_logical_shifted_reg
    6      73      59   ptrace.c(1120): compat_arch_ptrace
    8      50      30   cpuinfo.c(102): c_show
    8      64      50   topology.c(97): parse_cluster
    8      97      65   hw_breakpoint.c(660): watchpoint_handler
    9      44      32   traps.c(59): dump_mem
   11      71      55   signal32.c(129): copy_siginfo_to_user32
   31     198     172   module.c(184): apply_relocate_add

Complexity Histogram
Score-Range  Lin-Ct
    0-9        2206 ************************************************************
   10-19         55 *
   20-29          0
   30-39        172 *****

Scored procedure ct:       65
Non-comment line ct:     2433
Average line score:         7
25%-ile score:              3 (75% in higher score procs)
50%-ile score:              5 (half in higher score procs)
75%-ile score:              6 (25% in higher score procs)
Highest score:             31 (apply_relocate_add() in module.c)

cd ~/edev/linux/arch/arm64/kernel

complexity --histogram --score --thresh=3 `ls *.c`

procedure fpsimd_pm_init in fpsimd.c ended before final close bracket

procedure fpsimd_hotplug_init in fpsimd.c ended before final close bracket

Complexity Scores

Score | ln-ct | nc-lns| file-name(line): proc-name

3 28 17 perf_callchain.c(111): perf_callchain_user

3 20 18 insn.c(337): aarch64_insn_decode_immediate

3 21 19 io.c(27): __memcpy_fromio

3 21 19 io.c(56): __memcpy_toio

3 30 19 cpufeature.c(860): verify_local_cpu_capabilities

3 21 20 module.c(74): reloc_data

3 24 20 setup.c(199): request_standard_resources

3 27 20 alternative.c(89): __apply_alternatives

3 29 20 cpu_ops.c(53): cpu_read_enable_method

3 29 24 insn.c(362): aarch64_insn_encode_immediate

3 31 24 ptrace.c(76): ptrace_hbptriggered

3 54 24 kgdb.c(159): kgdb_arch_handle_exception

3 28 25 armv8_deprecated.c(145): update_insn_emulation_mode

3 32 25 debug-monitors.c(334): aarch32_break_handler

3 35 26 smp.c(413): acpi_map_gic_cpu_interface

3 42 26 process.c(249): copy_thread

3 58 27 perf_event.c(572): armv8pmu_handle_irq

3 32 28 hw_breakpoint.c(544): toggle_bp_registers

3 34 28 insn.c(1019): aarch64_insn_gen_data3

3 34 29 insn.c(519): aarch64_insn_gen_comp_branch_imm

3 56 29 setup.c(121): smp_build_mpidr_hash

3 35 30 insn.c(397): aarch64_insn_encode_register

3 42 31 signal.c(167): setup_sigframe

3 37 33 hw_breakpoint.c(349): arch_bp_generic_fields

3 49 34 setup.c(232): relocate_initrd

3 41 35 insn.c(708): aarch64_insn_gen_add_sub_imm

3 63 38 setup.c(292): setup_arch

3 109 57 cpufeature.c(469): update_cpu_features

4 46 26 smp.c(477): of_parse_and_init_cpus

4 38 31 traps.c(335): call_undef_hook

4 36 32 insn.c(924): aarch64_insn_gen_data1

4 49 33 armv8_deprecated.c(464): cp15barrier_handler

4 71 34 stacktrace.c(41): unwind_frame

4 42 35 ptrace.c(437): hw_break_set

4 42 37 insn.c(968): aarch64_insn_gen_data2

4 49 37 smp.c(708): handle_IPI

4 58 37 hw_breakpoint.c(231): hw_breakpoint_control

4 47 40 insn.c(757): aarch64_insn_gen_bitfield

4 54 44 ptrace.c(376): hw_break_get

4 60 44 armv8_deprecated.c(378): swp_handler

5 28 27 hw_breakpoint.c(198): hw_breakpoint_slot_setup

5 45 35 ptrace.c(672): compat_gpr_get

5 50 36 hw_breakpoint.c(764): reinstall_suspended_bps

5 59 37 hw_breakpoint.c(476): arch_validate_hwbkpt_settings

5 48 42 insn.c(811): aarch64_insn_gen_movewide

5 49 42 insn.c(868): aarch64_insn_gen_add_sub_shifted_reg

5 60 44 psci.c(36): cpu_psci_cpu_init_idle

5 49 46 insn.c(277): aarch64_get_imm_shift_mask

5 95 89 asm-offsets.c(34): main

6 34 32 cpufeature.c(792): __raw_read_system_reg

6 67 37 signal.c(332): do_signal

6 43 39 topology.c(50): parse_core

6 54 41 ptrace.c(724): compat_gpr_set

6 74 44 traps.c(147): dump_backtrace

6 55 49 insn.c(646): aarch64_insn_gen_load_store_pair

6 76 49 hw_breakpoint.c(393): arch_build_bp_info

6 71 52 hw_breakpoint.c(584): breakpoint_handler

6 61 54 insn.c(1062): aarch64_insn_gen_logical_shifted_reg

6 73 59 ptrace.c(1120): compat_arch_ptrace

8 50 30 cpuinfo.c(102): c_show

8 64 50 topology.c(97): parse_cluster

8 97 65 hw_breakpoint.c(660): watchpoint_handler

9 44 32 traps.c(59): dump_mem

11 71 55 signal32.c(129): copy_siginfo_to_user32

31 198 172 module.c(184): apply_relocate_add

Complexity Histogram

Score-Range Lin-Ct

0-9 2206 ************************************************************

10-19 55 *

20-29 0

30-39 172 *****

Scored procedure ct: 65

Non-comment line ct: 2433

Average line score: 7

25%-ile score: 3 (75% in higher score procs)

50%-ile score: 5 (half in higher score procs)

75%-ile score: 6 (25% in higher score procs)

Highest score: 31 (apply_relocate_add() in module.c)

The resulting table shows six information per line: the computed score, the number of lines between the opening and closing curly braces (ln-ct), the number […]

March 1, 2016May 29, 2017 by Jean-Luc Aufranc (CNXSoft) - 12 Comments

64-bit ARM (Aarch64) Instructions Boost Performance by 15 to 30% Compared to 32-bit ARM (Aarch32) Instructions

Yesterday was quite an eventful day with the launch of two low cost 64-bit ARM development boards, namely Raspberry Pi 3 and ODROID-C2, and as usual there were some pretty interesting discussions related to the launch of the boards in the comments section. One of the subject that came is that while Raspberry Pi 3 board is using a 64-bit processor, the operating systems are still compiled with 32-bit instructions (Aarch32) and even optimized for ARMv6, and they intend to keep it that way according to Eben Upton interview: Eben readily admits that not all the capabilities of the new parts are going to be used at launch, however. “Although it is a 64‑bit core, we’re using it as just a faster 32-bit core,” he reveals about the Pi 3’s central processing unit. “I can imagine there’d be some real benefits [to 64-bit code]. The downside is that you do […]

February 29, 2016March 1, 2016 by Jean-Luc Aufranc (CNXSoft) - 8 Comments

Geniatech ATV195e 4K TV Stick Features Amlogic S905 Processor, 802.11ac WiFi

While there are way too many Amlogic S905 TV boxes to keep up, the number of TV sticks based on the processor is fairly low, and until today I had only heard about Guleek A8 a few months ago, but I can’t even see it for sale anywhere.Potential reason include people have released TV stick are not that convenient, or electronic design houses had issues to cool the thing down, as we’ve seen even some full-size TV boxes have issues with cooling. Nevertheless, Geniatech has designed their own Amlogic S905 TV stick called ATV195e with 1GB RAM, 8GB flash, and 802.11ac WiFi. Geniatech ATV195e preliminary specifications: SoC – Amlogic S905 quad core ARM Cortex-A53 @ up to 2.0GHz with penta core Mali-450MP GPU up to 750MHz System Memory – 1GB DDR3 Storage – 8GB eMMC flash (2 to 32GB on-request) Video Output – HDMI 2.0 up to 4K @ 60Hz […]

February 29, 2016March 1, 2016 by Jean-Luc Aufranc (CNXSoft) - 46 Comments

ODROID-C2 64-Bit ARM Development Board is Now Available for Purchase for $40

ODROID-C2 is a quad core 64-bit ARM development board based on Amlogic S905 processor with 2GB RAM that was planned to launch in early March, but maybe unsurprisingly, Hardkernel decided to launch their latest board, the very same day as Raspberry Pi 3 launch. We already knew the specifications, but it’s always useful to mind ourselves of the details: SoC – Amlogic S905 quad core cortex-A53 processor @ 2.0 GHz with 3+2 cores Mali-450 GPU System Memory – 2GB DDR3 SDRAM Storage – eMMC module socket with 8, 16, 32, or 64GB module by Toshiba or Sandisk + micro SD slot supporting UHS-1 SD cards. Video Output – HDMI 2.0 up to 4K @ 60 Hz Connectivity – Gigabit Ethernet (Realtek RTL8211F) USB – 4x USB 2.0 host ports + micro USB OTG port Expansion Header 40-pin header with GPIO, I2C, UART, and ADC ; All I/Os are 3.3V, except […]