 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
ELM327DSC Datasheet(PDF) 9 Page - ELM Electronics |
|
||||||||||||||||||||||||||||||
ELM327DSC Datasheet(HTML) 9 Page - ELM Electronics |
|
|
9 / 51 page  9 of 51 ELM327 ELM327DSC Elm Electronics – Circuits for the Hobbyist www.elmelectronics.com CFC0 and CFC1 [ CAN Flow Control off or on ] The ISO 15765-4 protocol expects a “Flow Control” message to always be sent in response to a “First Frame” message. The ELM327 automatically sends these, without any intervention by the user. If experimenting with a non-OBD system, it may be desirable to turn this automatic response off, and the AT CFC0 command has been provided for that purpose. The default setting is CFC1 - Flow Controls on. Note that during monitoring (AT MA, MR, or MT), there are never any Flow Controls sent no matter what the CFC option is set to. CM hhh [ set the CAN ID Mask to hhh ] There can be a great many messages being transmitted in a CAN system at any one time. In order to limit what the ELM327 views, there needs to be a system of filtering out the relevant ones from all the others. This is accomplished by the filter, which works in conjunction with the mask. A mask is a group of bits that show the ELM327 which bits in the filter are relevant, and which ones can be ignored. A ‘must match’ condition is signaled by setting a mask bit to '1', while a 'don't care' is signaled by setting a bit to '0'. This three digit variation of the CM command is used to provide mask values for 11 bit ID systems (the most significant bit is always ignored). Note that a common storage location is used internally for the 29 bit and 11 bit masks, so an 11 bit mask could conceivably be assigned with the next command (CM hh hh hh hh), should you wish to do the extra typing. The values are right justified, so you would need to provide five leading zeros followed by the three mask bytes. CM hh hh hh hh [ set the CAN ID Mask to hhhhhhhh ] This command is used to assign mask values for 29 bit ID systems. See the discussion under the CM hhh command – it is essentially identical, except for the length. Note that the three most significant bits that you provide in the first digit will be ignored. CP hh [ set CAN Priority bits to hh ] This command is used to set the five most significant bits in a 29 bit CAN ID word (the other 24 bits are set with the AT SH command). Some systems use several of these bits to assign a priority value to messages, which is how the command was named. Any bits provided in excess of the five required will be ignored, and not stored by the ELM327 (it only uses the five least significant bits of this byte). The default value for these priority bits is hex 18. CS [ show the CAN Status ] The CAN protocol requires that statistics be kept regarding the number of transmit and receive errors detected. If there should be a significant number of them, the device can even go off-line in order not to affect other data on the bus, should there be a hardware or software fault. The AT CS command lets you see both the Tx and the Rx error counts. If the transmitter should be off (count >FF), you will see ‘OFF’ rather than a specific count. CV dddd [ Calibrate the Voltage to dd.dd volts ] The voltage reading that the ELM327 presents for an AT RV reading can be calibrated with this command. The argument (‘dddd’) must always be provided as 4 digits, with no decimal point (it assumes that a decimal place is between the second and the third digits). To use this calibration feature, simply use a meter with sufficient accuracy to read the actual input voltage. If, for example, the ELM327 consistently says the voltage is 12.2V when you measure 11.99 volts, simply issue AT CV 1199, and the device will recalibrate itself for the provided voltage (it should then read 12.0V due to roundoff). If you use a test voltage that is less than 10 volts, don’t forget to add a leading zero (that is, 9.02 volts should be entered as AT CV 0902). D [ set all to Defaults ] This command is used to set the options to their default (or factory) settings, as when power is first applied. The last stored protocol will be retrieved from memory, and will become the current setting (possibly closing other protocols that are active). Any settings that the user had made for custom headers, filters, or masks will be restored to their default values, and all timer settings will also be restored to their defaults. AT Commands (continued) |
Similar Part No. - ELM327DSC |
|
Similar Description - ELM327DSC |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
