Post by thread:[PIC]: interfacing PIC16F877 with AD7713(adc)

Hello Sivaram & PIC.ers, One of my designs uses the I2C bus, controlled by the 16f877 MSSP. It *also* has to communicate with an ad7715 16bit adc, this has an SPI digital i/f. Apparantly it's possible to run both I2C and SPI from one MSSP in the PIC, but my attempts failed so I ended up doing the SPI > ad7715 in software. No big deal... at least the SPI bit, as for getting the adc and PIC to talk sense to each other - a whole nother deal. If this is of any interest to you let me know. best regards, John {Quote hidden}>Date: Thu, 27 Feb 2003 17:27:59 -0500 >From: Sivaram Cheekiralla <spam_OUTsivaramTakeThisOuTMIT.EDU> >Subject: [pic] interfacing PIC16F877 with AD7713(adc) > >Hi, > I am trying to interface an adc(AD7713 from Analog Devices, 24 bit >resolution) with PIC16F877. The adc can communicate with microcontrollers >using synchronous serial port communication (either SPI or using the >Synchronous mode of the USART feature). I don't want to use the RX/TX pins >of the 877 for interfacing with adc,as I want to use them to connect to a >serial port of a PC. I am forced to use the SPI, but there is only one data >line for the adc and I need 2 lines (for SDI and SDO) to use the SPI feature > on 877. Is there anyway to use/apply "wired-or" kind of connection > (available in the 68HC11 on the SPI ports) with the 877. > >Thanks in Advance, >Sivaram > eMail from the desk of John Sanderson. JS Controls, PO Box 1887, Boksburg 1460, Rep. of S. Africa. Tel / Voice / Fax : 011 893 4154 email : jsand @pixie.co.za Cell : 082 741 6275 Manufacturer & Purveyor of laboratory force testing apparatus and related products & services. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Hi, We use an AD7710 in a project and have a 5.1K resistor between SDO and SDI (MOSI and MISO). The SDI line is connected directly to the SDATA I/O line of the 7710. There are additional pins going to the A0, RFS and TFS lines to select registers and reading/writing. The same board also has conventional SPI devices like EEROMs and those signals are connected directly to the SDI, SDO and SCLK of the 877. I have one function for all the SPI communications and a special function for the AD7710 communications and I do use the hardware SPI registers to do all this. John Dammeyer Wireless CAN with the CANRF module now available. http://www.autoartisans.com/products Automation Artisans Inc. Ph. 1 250 544 4950 > {Original Message removed}

{Quote hidden}> > >Date: Thu, 27 Feb 2003 17:27:59 -0500 > > >From: Sivaram Cheekiralla <.....sivaramKILLspam@spam@MIT.EDU> > > >Subject: [pic] interfacing PIC16F877 with AD7713(adc) > > > > > >Hi, > > > I am trying to interface an adc(AD7713 from Analog Devices, 24 bit > > >resolution) with PIC16F877. The adc can communicate with > > microcontrollers > > >using synchronous serial port communication (either SPI or using the > > >Synchronous mode of the USART feature). I don't want to use > > the RX/TX pins > > >of the 877 for interfacing with adc,as I want to use them > > to connect to a > > >serial port of a PC. I am forced to use the SPI, but there > > is only one data > > >line for the adc and I need 2 lines (for SDI and SDO) to use the SPI > > feature > > > on 877. Is there anyway to use/apply "wired-or" kind of connection > > > (available in the 68HC11 on the SPI ports) with the 877. > > > > > >Thanks in Advance, > > >Sivaram > > {Original Message removed}