i am using a A20 OLinuXino Micro 4GB from Olimex with Debian on SD Card.
I want to use the GPIOs and have some short question about the configuration of the GPIOs. The GPIO-1 connector on the board has pins numbered from 1 to 39. In the manual I have entries like that:
Pin # | Signal name | Processor pin
23 | PG9 | C19
...
39 | LRADC1 | AB22
In the fex file, I find this:
[gpio_para]
gpio_used = 1
gpio_num = 64
...
gpio_pin_10 = port:PG09<0><default><default><default>
How is defined that the processor pin C19 is routed to port PG9?
And port means exactly what?
How is defined that the port PG9 is routed to pin23 of the connector?
Can the gpio_pin_10 designation be chosen arbitrarily?
At the end I would like to use the LRADC1, to sample a signal, but the fex file doesn't have any LRADC1 entry. Why is that?
Maybe somebody could answer may questions in 2 or 3 sentences so it makes sense to the rest of what I read. Thanks!
Please take a look at A20-OLinuXino-MICRO schematics. You can find wiring:
PG09 - C19
PG10 - D18
PG11 - C18
(...)
In mentioned schematics is also section GPIO EXTENSION in which you can find which A20 SoC pin is assigned to which GPIO:
PG09 - 23 GPIO-1
PG10 - 25 GPIO-1
According to Wikipedia:
A GPIO port is a group of GPIO pins (typically 8 GPIO pins) arranged in a group and controlled as a group.
Mapping between physical pin and pin exposed through fex file to operating system is arbitrary. Of course to get correct results you have to assign GPIO ping not. I don't think that fex compiler check anything other then syntax.
In case LRADC0 (again schematics) it us used for buttons (vol +/-, menu, search, ...) and LRADC1 is exposed through GPIO-1 pin 39.
Related
TMP102 chip( http://www.ti.com/lit/ds/symlink/tmp102.pdf ) can have multiple I2c slave addresses. It has an address pin called ADD0(Section 5) which can be used to select multiple addresses(Section 7.3.4). The logic level at that pin can be used to select a particular TMP102 slave device. According to table 4, 4 addresses are possible. I do understand that connecting the pin to high or low voltage will produce two different addresses. But the table mentions that we can use SDA and SCL pins for two different addresses. I am not sure how this works. Can anyone explain how can this be used and how can we use multiple TMP102 devices based on SDA and SCL pins.
The logic level at that pin can be used to select a particular TMP102 slave device
That is not the purpose of ADD0 - it is a configuration pin, not a select pin. It is not used to select the device; I2C addresses are part of the data stream on SDA, there is no "select" pin as there is on SPI for example.
Rather, ADD0 is used to define the address of each device to one of four defined in Table 4. Those addresses being one of 0x48, 0x49, 0x4A or 0x4B depending on connection of ADD0 to GND, V+, SDA or SDL respectively. Like so:
How the device determines the address is not revealed in the datasheet and you don't really need to know, but given:
Public domain image by Marcin Floryan from https://en.wikipedia.org/wiki/I%C2%B2C
at the start condition at the falling edge of SDA the following occurs:
ADDR ADD0 SDA SCL
0x48 0 v 1
0x49 1 v 1
0x4A v v 1
0x4B 1 v 1
Then on the next falling edge SCL
ADDR ADD0 SDA SCL
0x48 0 0 v
0x49 1 0 v
0x4A 0 0 v
0x4B v 0 v
So it is possible with suitable sequential logic to latch the address by the end of the S phase and before B1 which is sufficient because the address match does not occur until B7, and all devices on the bus must listen for the address.
You connect ADD0 to SDA/SCL to get those other addresses. The table shows the address you get based on what ADD0 is connected to.
I would provide din+ to A1 and din- to A2, on pin connector on PM2 module, connecting to FPGA, but I have only 1 input port "din" in top level vhdl design module connected to AG7 pin on FPGA. How to go about connection in UCF file ?
PM2 Pin - A1, A2
FPGA pin -AG7, AG6
FPGA bank VCCO - 2.5v, 2.5v
Pin Function - LVDS pair 100 ohm differential impedance; can also be used as single-ended
You have to manually instantiate the differential input buffer. For Xilinx it will be IBUFDS in the Unisim library. Either modify your port to have two pins for din and add the buffer in the existing design or write a simple wrapper that converts the diff. pairs to single-ended and pass that into the current port.
I was wondering if anyone could help me understand difference between ISO 8583 Field 22 i.e. POS Entry Mode. I already know that:
52 means ICC Card
80 in case of fallback
But what I want to know is difference between
22 (Magnetic Stripe)
and 90
Can anyone help me on this?
The length of Field 22 usually 3-digits (or 4-digits in case it is BCD packed into two Bytes) in protocols based on ISO 8583:1987 or 12-digits in case protocols based on ISO 8583:1993 version. Customized protocols could use different sub-fields content and values meaning behind.
While you use short values in the requested question, I guess, your Field 22 based on ISO 8583:1987 version and you lost the leading and/or ending zero. So, your sample values becomes 3 digits length - 052, 800, 022, and 090 or 900.
Usually the 3-digits Field 22 splited into two sub-fields:
Position 1 and 2 - Personal Account Number (PAN) Entry (or capability);
Position 3 - Personal Identification Number (PIN) Entry (or capability);
Here are the possible interpretations:
02 - PAN auto-entry via magnetic stripe, track data is not required, 2 - no PIN.
05 - PAN auto-entry via chip, 2 - no PIN.
09 - E-Commerce, 0 - unknown PIN capability.
80 - Fallback to magnetic stripe, 0 - unknown PIN capability.
90 - PAN auto-entry via magnetic stripe, track data should be transmitted within the authorization request, 0 - unknown PIN capability.
etc.
90 used in case track data present in the ISO 8583 request message, 02 - if, for same reason, acquirer or terminal device not qualified to transfer track data in the request messages.
Depending of protocol requirements could be exceptions with Field 22 values. It is usually checked during the terminal device and communication interface certifications.
I will elaborate few things here. From above comments I can see that 09 is for E commerce transactions,but as per my knowledge for E commerce transactions we should use PAN Entry mode as 01(manual entry). Because for card not present transactions entry mode has always in manually.
POS Entry mode says whether the particular transaction is E commerce or POS. The possible values are :
01 Manual entry
02 Magnetic Stripe,track 2 data will ignore
05 Smart card,track 2 data required
90 Magnetic stripe no track 2 data
91 contactless card
95 Smart card , track2 data not required
Thanks share your ideas on this
I have a VW Golf 4, which is quite old and talks KWP 2000 (ISO 9141) on its CAN bus. I use a dongle powered by ELM 327, connected to the OBD-2 port of the car.
I am trying to send messages individually to each ECU. I tried to change the header of the messages:
AT SH 48 XX F1 (I hoped XX would be the ECU ID; 48 is the flag for "use physical addressing"). Any command I issue (e.g. tried 3E for "tester present") returns NO DATA (I disabled automatic timeouts and set the timeout to maximum value).
Is there a way to send messages directly to the ECU? I am not interested in the set of data provided via OBD-2, neither do I want to re-flash the ECUs. At the moment I just try to find out which ECUs are available on the bus.
Thanks!
VW works on Transport Protocol TP 2.0, hence you need to initialize with 0x200 header.
https://jazdw.net/tp20
See above link for more info.
I've got three XBees. 2x PROs and a standard, all series 2s.
I've configured one PRO and one standard to be router/endpoints on channel 0 and PAN 234 (this is the default channel and PAN ID when selecting the "XBP24-B"/"XB24-B" "ZNET2.5 ROUTER/END DEVICE AT" profile (version 1247 for both).
However the one PRO I've set with the "ZNET 2.5 COORDINATOR AT" profile has a channel of E (though if I keep flashing the device with the same profile, this changes from 12-F).
Obviously if the coordinator doesn't have the same channel, nothing will work, but I can't see any way of setting the channel manually..?
The CH setting in X-CTU is read only, and I can see any other UI element to change the channel:
I've even been into the terminal and typed (words in brackets are what the terminal returns):
+++ (OK)
ATCH (E)
ATCH0 (ERROR)
ATCH 0 (ERROR)
ATCH00 (ERROR)
ATCH 00 (ERROR)
ATCH E (ERROR)
ATCHE (ERROR)
I've Googled and Googled to no avail. incredibly frustrating, can anyone help?!
I've had them working previous as a matter of fluke as I kept flashing the hardware until the channel numbers match up, but this is obviously ridiculous!
Channel selection with the XBee ZB (S2, S2B, S2C) series of modules works differently than with the XBee 802.15.4 (S1) modules. Channel selection is automatic with ZB (as opposed to it being manual with the 802.15.4 modules).
You normally never need to manipulate the channel selection parameters with ZB. Modules find each other and associate with each other if they can.
If your modules just can't seem to find each other it usually comes down to a mismatch in the PAN settings (ID), security settings (LK), or network joining permission settings on the coordinator (NJ).
Not a lot of information exists on the web outside of the Digi's XBee ZB OEM manual. For reference sake, channel selection with ZB works like this:
XBee ZB Coordinator is powered up
The XBee ZB Coordinator reads its SC parameter and builds a list of candidate channels to scan
The XBee ZB Coordinator then performs an energy scan on each candidate channel
The XBee ZB Coordinator then chooses the channel with the least amount of energy on it
This procedure aims to pick a channel with the least amount of noise on it be it from microwave ovens, WiFi networks, or anything else that might be transmitting on the 2.4GHz frequency band.
Any router or end devices joining a network with consult their SC parameters first, then they will try and search for networks they can join which match their PAN and security parameters. They will join and stay joined to the first network they can--with some minor exceptions (see the JV and NW parameters, for example).
If you want to force a channel selection you must set the SC parameter to enable only a single channel. The SC parameter is a bitmask1. Each bit set in the mask will enable one additional channel. What's tricky about this parameter is that the first bit (bit 0) is not channel 0, it's channel 11 (0x0B). For ease of use, if you wanted to lock an XBee ZB to a single channel here would be the values:
+---------------+---------------+------------------+-------------------------+
| Channel (Dec) | Channel (Hex) | XBee ZB SC Value | XBee Availability |
+---------------+---------------+------------------+-------------------------+
| 11 | 0xB | 0x1 | All |
| 12 | 0xC | 0x2 | All |
| 13 | 0xD | 0x4 | All |
| 14 | 0xE | 0x8 | All |
| 15 | 0xF | 0x10 | All |
| 16 | 0x10 | 0x20 | All |
| 17 | 0x11 | 0x40 | All |
| 18 | 0x12 | 0x80 | All |
| 19 | 0x13 | 0x100 | All |
| 20 | 0x14 | 0x200 | All |
| 21 | 0x15 | 0x400 | All |
| 22 | 0x16 | 0x800 | All |
| 23 | 0x17 | 0x1000 | All |
| 24 | 0x18 | 0x2000 | All |
| 25 | 0x19 | 0x4000 | S1, S2B, S2C (not S2) |
| 26 | 0x1A | 0x8000 | S1 only |
+---------------+---------------+------------------+-------------------------+
Obviously if the coordinator doesn't
have the same channel, nothing will
work, but I can't see any way of
setting the channel manually..?
I'm not sure if what you say above is right. From http://ftp1.digi.com/support/documentation/90000976_C.pdf (you should look at the correct version for your hardware, though), it looks like the purpose of a coordinator is to automatically determine the channel:
Coordinator Operation
Forming a Network
The coordinator is responsible for
selecting the channel, PAN ID (16-bit
and 64-bit), security policy, and
stack profile for a network. Since a
coordinator is the only device type
that can start a network, each ZigBee
network must have one coordinator.
After the coordinator has started a
network, it can allow new devices to
join the network. It can also route
data packets and communicate with
other devices on the network. To
ensure the coordinator starts on a
good channel and unused PAN ID, the
coordinator performs a series of scans
to discover any RF activity on
different channels (energy scan) and
to discover any nearby operating PANs
(PAN scan). The process for selecting
the channel and PAN ID are described
in the following sections.
Channel Selection
When starting a
network, the coordinator must select a
"good" channel for the network to
operate on. To do this, it performs an
energy scan on multiple channels
(frequencies) to detect energy levels
on each channel. Channels with
excessive energy levels are removed
from its list of potential channels to
start on.
I've actually never used the Digi XBee radios (just some of their other radios), so I don't know much about coordinators. I think that their user interface typically does expose all of the valid commands, so it probably won't work to try sending them manually (as you discovered).
You may find more experts on the Digi forums.
Hmm. strange, keep going over the settings again and finally got it working with 2-way comms?! :S
Setup one a coordinator
Setup other two as router/end devices
Set the Device High (DH) to 0 and the Device Low (DL) to FFFF (this means everything sent from this module should be received by everyone)
Set Negotiate Channel to 1 (Enabled), which means the only time a router/end device can set it's own channel is when it finds a coordinator on the same channel (this clearly wasn't happening in my case)
Everything else was left as default.
Leave coordinator powered on when configuring router/end devices so you can check they pair correctly.
As I said, I've used this configuration before and it just didn't work, so I don't know what kicked it into life this time, but it worked?!
One thing to take into account is that ZigBee channels extend from 11 to 26, zero is not a valid option.
Since that's the case, are you able to try the command ATCH11 ?
If that command succeeds, then perhaps the ATCH command wants a decimal input between 11 and 26?