[beagleboard] Re: header file for CCSv6 & PRU
Hi, I found all the required information in the AM335x TRM pdf file. You need to offsets for the I2C module you are using and the base address from the memory map. The programming sequence is all detailed in there under the I2C section. On Tuesday, 21 August 2018 12:44:01 UTC+1, Gaurav S wrote: > > Hugh, > Thanks for sharing your research. > Any chance you could also include a reference (ie where did you find this > info)? > > Thanks > > On Friday, August 17, 2018 at 9:43:47 AM UTC-5, Hugh Frater wrote: >> >> I forgot this from my previous post: >> >> /* I2C2 register offsets */ >> >> #define I2C2_STATUSRAW (*((volatile unsigned int*)0x4819C024)) >> #define I2C2_CNT (*((volatile unsigned int*)0x4819C098)) >> #define I2C2_SA (*((volatile unsigned int*)0x4819C0AC)) >> #define I2C2_DATA (*((volatile unsigned int*)0x4819C09C)) >> #define I2C2_CON (*((volatile unsigned int*)0x4819C0A4)) >> #define I2C2_SCLL (*((volatile unsigned int*)0x4819C0B4)) >> #define I2C2_SCLH (*((volatile unsigned int*)0x4819C0B8)) >> #define I2C2_PSC (*((volatile unsigned int*)0x4819C0B0)) >> >> I couldn't be bothered to setup a header file for this lot, so just >> stuffed it in the top of my PRU code... Registers for other I2C modules are >> in the memory map from the am335X_trm >> >> On Tuesday, 14 August 2018 12:29:12 UTC+1, Hugh Frater wrote: >>> >>> Does anyone know the header file I need to include to get access to the >>> i2c2 control registers from within the PRU subsystem? Having a hard time >>> getting any info and my google-foo is usually pretty decent... >>> >> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/49a46d7b-2197-44b9-a6b7-b903e654704a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[beagleboard] Re: header file for CCSv6 & PRU
Hugh, Thanks for sharing your research. Any chance you could also include a reference (ie where did you find this info)? Thanks On Friday, August 17, 2018 at 9:43:47 AM UTC-5, Hugh Frater wrote: > > I forgot this from my previous post: > > /* I2C2 register offsets */ > > #define I2C2_STATUSRAW (*((volatile unsigned int*)0x4819C024)) > #define I2C2_CNT (*((volatile unsigned int*)0x4819C098)) > #define I2C2_SA (*((volatile unsigned int*)0x4819C0AC)) > #define I2C2_DATA (*((volatile unsigned int*)0x4819C09C)) > #define I2C2_CON (*((volatile unsigned int*)0x4819C0A4)) > #define I2C2_SCLL (*((volatile unsigned int*)0x4819C0B4)) > #define I2C2_SCLH (*((volatile unsigned int*)0x4819C0B8)) > #define I2C2_PSC (*((volatile unsigned int*)0x4819C0B0)) > > I couldn't be bothered to setup a header file for this lot, so just > stuffed it in the top of my PRU code... Registers for other I2C modules are > in the memory map from the am335X_trm > > On Tuesday, 14 August 2018 12:29:12 UTC+1, Hugh Frater wrote: >> >> Does anyone know the header file I need to include to get access to the >> i2c2 control registers from within the PRU subsystem? Having a hard time >> getting any info and my google-foo is usually pretty decent... >> > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/ec0bcc70-1d82-4877-b074-c762337ff4bd%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[beagleboard] Re: header file for CCSv6 & PRU
I forgot this from my previous post: /* I2C2 register offsets */ #define I2C2_STATUSRAW (*((volatile unsigned int*)0x4819C024)) #define I2C2_CNT (*((volatile unsigned int*)0x4819C098)) #define I2C2_SA (*((volatile unsigned int*)0x4819C0AC)) #define I2C2_DATA (*((volatile unsigned int*)0x4819C09C)) #define I2C2_CON (*((volatile unsigned int*)0x4819C0A4)) #define I2C2_SCLL (*((volatile unsigned int*)0x4819C0B4)) #define I2C2_SCLH (*((volatile unsigned int*)0x4819C0B8)) #define I2C2_PSC (*((volatile unsigned int*)0x4819C0B0)) I couldn't be bothered to setup a header file for this lot, so just stuffed it in the top of my PRU code... Registers for other I2C modules are in the memory map from the am335X_trm On Tuesday, 14 August 2018 12:29:12 UTC+1, Hugh Frater wrote: > > Does anyone know the header file I need to include to get access to the > i2c2 control registers from within the PRU subsystem? Having a hard time > getting any info and my google-foo is usually pretty decent... > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/9145aa05-a10f-4188-a293-b1cb0358392a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[beagleboard] Re: header file for CCSv6 & PRU
An update: 1. Enable the i2c peripheral clock: #define CM_PER_I2C2 (*((volatile unsigned int *)0x44E00044)) /* Enable I2C2 clock signal generation */ while (!(CM_PER_I2C2 & 0x2)) CM_PER_I2C2 |= 0x2; 2. Setup the registers: /* * set I2C2_PSC register to 0x0B * set I2C2_SCCL register to 0x0D * set I2C2_SCCH register to 0x0F * set I2C2_CON register to 1000 0110 (0x8600) * set I2C2_SA register to 0x2E (address of MCP4641) * set I2C2_CNT register to 2 (data length) */ I2C2_PSC = 0x000B; I2C2_SCLL = 0x000D; I2C2_SCLH = 0x000F; I2C2_CON = 0x8600; I2C2_SA = i2cPotAddress; I2C2_CNT = 2; 3. You can now program the device: /* * poll 'busy bit' in I2C2_STATUSRAW register (bit 12) until it is zero * set start/stop bits in I2C2_CON register to initiate a transfer * poll XRDY bit in I2C2_STATUSRAW register (bit 4) until it is non-zero * load 1st byte of data into I2C2_DATA register * poll XRDY bit in I2C2_STATUSRAW register (bit 4) until it is non-zero * load 2nd byte of data into I2C2_DATA register */ while (I2C2_STATUSRAW & 0x1000); //poll 'busy bit' in I2C2_STATUSRAW register (bit 12) until it is zero I2C2_CON = 0x8603; while (!I2C2_STATUSRAW & 0x0010); //poll XRDY bit in I2C2_STATUSRAW register (bit 4) until it is non-zero I2C2_DATA = torqueWiper; while (!I2C2_STATUSRAW & 0x0010); //poll XRDY bit in I2C2_STATUSRAW register (bit 4) until it is non-zero I2C2_DATA = 0x55; 4. The kernel mode (and bonescript) i2c drivers will put the device to sleep and disable the clock after every transfer, so to access it from the PRU you need to setup the registers each time you want to access a device on the bus. Hope that helps someone... On Tuesday, 14 August 2018 12:29:12 UTC+1, Hugh Frater wrote: > > Does anyone know the header file I need to include to get access to the > i2c2 control registers from within the PRU subsystem? Having a hard time > getting any info and my google-foo is usually pretty decent... > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/4f509d76-975c-4f6e-920d-5e3963d2f364%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
