Re: [Tinyos-help] I2C problem in micaz and MDA300
Thank you for your answer. I check with an oscilloscope and find out the bug. It was in the code I wrote for managing the Digital I/O. Very simple error but sometimes those are the most difficult to debug. In fact once I I2C.Write a value on the Digital port the changed bit is of course kept in the values that are I2C.Read later. I changed the code making independent the I2C.Read from the first two bits that are used for the Relays control, and that solved the problem. Franco Di Persio. -Mensaje original- De: Michael Schippling [mailto:sc...@santafe.edu] Enviado el: martes, 17 de julio de 2012 20:00 Para: francodipersio CC: tinyos-help@millennium.berkeley.edu Asunto: Re: [Tinyos-help] I2C problem in micaz and MDA300 Try to compare the low level I2C code and see what's different between T1 and T2. I think the last version of T1 had the atmega code in: tinyos-1.x/tos/platform/avrmote/HPLI2CM.nc If you search for schip tinyos I2C you'll find some help list discussion of my battles with the Moteworks all-in-software bit banging code used by the iris in: MoteWorks/tos/platform/atm128/I2CM.nc Specifically the spec calls for a wait state mechanism driven by the slave device which was not implemented in the software. I would hope that a hardware impl does this correctly, but who knows... I found this datasheet to have a good description of I2C operation if you need to start poking an oscilloscope or logic analyzer at it: http://www.nxp.com/acrobat_download/usermanuals/UM10204_3.pdf MS francodipersio wrote: Hi, I am using Micaz and Tinyos-2.1.1 together with the MDA300 sensorboard. Taking as base the code from http://tinyos.cvs.sourceforge.net/viewvc/tinyos/tinyos-2.x-contrib/uoit/mda3 00ca/ , I am actually trying to complete the driver for controlling the 8-Channel Digital I/O. On MDA300 the hardware component proposed for the 8-Channel Digital I/O is the PCF8574A and its work via the I2C interface. Two of the 8 channels are used for controlling two Relays. In order to control the I2C bus I am using the codes from .tos\chips\atm128\i2c (by the way, I have downloaded the last version from the trunk). At power on, the 8 channel ports on the PCF8574A are high (value 0xFF) I have no problem in reading the data from the device, once an Interrupt change from high to low the correspondent pin on the 8 channel ports, but the problems arise when I try to write on the device in order to control the two relays. In this case the PCF8574A stop to work. I am sure is not a hardware problem, because with the Tinyos-1.x everything is working properly. In order to debug the problem I check the Atm128I2CMasterPacketP.nc file, but apparently everything goes smoothly being the status codes called by I2C.status the proper ones (table 88 - Status Codes for Master Transmitter Mode in the ATmega128 Manual) along the writing process. So, I presume that something wrong is happening after data has been transmitted and ACK has been received, thus during and after the STOP condition is sent. Also I have noted that the data is reaching the device, because I verified that the correspondent bit on the PCF8574A port is effectively changed, but after that the device become irresponsive. Also, if I try to write the default value (0xFF) and in this case everything go fine and the device keep working. Somebody has any idea how to solve the problem? There is a way with the Atm128I2CMasterPacketP to check the status just before and after the STOP condition is sent? I should check with an oscilloscope the I2C behaviour, but I am not so familiar with them, so I hope to solve the problem in other way. Thank you in advance Franco Di Persio ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
Re: [Tinyos-help] I2C problem in micaz and MDA300
Hi, I used the debug a lot the MasterPacketP. The best way was to add some DiagMsg to every command/event in the HplAtm128I2CBusP. Andris On Tue, Jul 17, 2012 at 12:33 PM, francodipersio francodiper...@sestosenso.es wrote: Hi, I am using Micaz and Tinyos-2.1.1 together with the MDA300 sensorboard. Taking as base the code from http://tinyos.cvs.sourceforge.net/viewvc/tinyos/tinyos-2.x-contrib/uoit/mda300ca/ , I am actually trying to complete the driver for controlling the 8-Channel Digital I/O. On MDA300 the hardware component proposed for the 8-Channel Digital I/O is the PCF8574A and its work via the I2C interface. Two of the 8 channels are used for controlling two Relays. In order to control the I2C bus I am using the codes from …tos\chips\atm128\i2c (by the way, I have downloaded the last version from the trunk). At power on, the 8 channel ports on the PCF8574A are high (value 0xFF) I have no problem in reading the data from the device, once an Interrupt change from high to low the correspondent pin on the 8 channel ports, but the problems arise when I try to write on the device in order to control the two relays. In this case the PCF8574A stop to work. I am sure is not a hardware problem, because with the Tinyos-1.x everything is working properly. In order to debug the problem I check the Atm128I2CMasterPacketP.nc file, but apparently everything goes smoothly being the status codes called by I2C.status the proper ones (table 88 – Status Codes for Master Transmitter Mode in the ATmega128 Manual) along the writing process. So, I presume that something wrong is happening after data has been transmitted and ACK has been received, thus during and after the STOP condition is sent. Also I have noted that the data is reaching the device, because I verified that the correspondent bit on the PCF8574A port is effectively changed, but after that the device become irresponsive. Also, if I try to write the default value (0xFF) and in this case everything go fine and the device keep working. Somebody has any idea how to solve the problem? There is a way with the Atm128I2CMasterPacketP to check the status just before and after the STOP condition is sent? I should check with an oscilloscope the I2C behaviour, but I am not so familiar with them, so I hope to solve the problem in other way. Thank you in advance Franco Di Persio ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
Re: [Tinyos-help] I2C problem in micaz and MDA300
Try to compare the low level I2C code and see what's different between T1 and T2. I think the last version of T1 had the atmega code in: tinyos-1.x/tos/platform/avrmote/HPLI2CM.nc If you search for schip tinyos I2C you'll find some help list discussion of my battles with the Moteworks all-in-software bit banging code used by the iris in: MoteWorks/tos/platform/atm128/I2CM.nc Specifically the spec calls for a wait state mechanism driven by the slave device which was not implemented in the software. I would hope that a hardware impl does this correctly, but who knows... I found this datasheet to have a good description of I2C operation if you need to start poking an oscilloscope or logic analyzer at it: http://www.nxp.com/acrobat_download/usermanuals/UM10204_3.pdf MS francodipersio wrote: Hi, I am using Micaz and Tinyos-2.1.1 together with the MDA300 sensorboard. Taking as base the code from http://tinyos.cvs.sourceforge.net/viewvc/tinyos/tinyos-2.x-contrib/uoit/mda300ca/ , I am actually trying to complete the driver for controlling the 8-Channel Digital I/O. On MDA300 the hardware component proposed for the 8-Channel Digital I/O is the PCF8574A and its work via the I2C interface. Two of the 8 channels are used for controlling two Relays. In order to control the I2C bus I am using the codes from …tos\chips\atm128\i2c (by the way, I have downloaded the last version from the trunk). At power on, the 8 channel ports on the PCF8574A are high (value 0xFF) I have no problem in reading the data from the device, once an Interrupt change from high to low the correspondent pin on the 8 channel ports, but the problems arise when I try to write on the device in order to control the two relays. In this case the PCF8574A stop to work. I am sure is not a hardware problem, because with the Tinyos-1.x everything is working properly. In order to debug the problem I check the Atm128I2CMasterPacketP.nc file, but apparently everything goes smoothly being the status codes called by I2C.status the proper ones (table 88 – Status Codes for Master Transmitter Mode in the ATmega128 Manual) along the writing process. So, I presume that something wrong is happening after data has been transmitted and ACK has been received, thus during and after the STOP condition is sent. Also I have noted that the data is reaching the device, because I verified that the correspondent bit on the PCF8574A port is effectively changed, but after that the device become irresponsive. Also, if I try to write the default value (0xFF) and in this case everything go fine and the device keep working. Somebody has any idea how to solve the problem? There is a way with the Atm128I2CMasterPacketP to check the status just before and after the STOP condition is sent? I should check with an oscilloscope the I2C behaviour, but I am not so familiar with them, so I hope to solve the problem in other way. Thank you in advance Franco Di Persio ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help ___ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
