YAP-II PICMicro Programmer

Transcription

1 YAP-II PICMicro Programmer The YAP-II is an In Circuit Serial Programmer ( ICSP ) for Microchip some low-end and midrange PICmicro Eight Bit Microcontrollers. The programmer is controlled by a wide variety of Host systems that are connected to the programmer via RS-232. Along with providing a programming interface, the YAP-II is also a circuit development system with controllable power supply, bread board and a set of simple interfaces that can be used to test out applications. This programmer was designed as part of Programming and Customizing the PICmicro Second Edition and provides additional capabilities not present in the original YAP. These enhanced capabilities include the ability to program parts, program parts with built in oscillators (and requiring the saving of calibration values) and wire applications directly to the board. Now available for the YAP-II is a Microsoft Windows interface to simplify downloading of applications into the YAP-II as well as executing the applications with the built in hardware interfaces. This interface resembles the screen shot shown below: Installing and using this software is described later in this document. This application can be downloaded from the Wirz Electronics web site.

2 This document will be updated continuously as more features are made available to YAP-II. Check the page header and footer for the current document number and release date. Note that the release number of this document matches the release number of the YAP-II Windows Interface. Information is contained later in this document to explain how the YAP-II Windows Interface is installed and deleted (for update). The YAP-II Windows Interface Software supports the following PICmicro devices: Part Number Device Pins Program Memory Size Program Memory Type PIC16C554 PIC16C556 PIC16C558 PIC16C61 PIC16C62(A-B) PIC16C63(A) PIC16C620 PIC16C621 PIC16C622 PIC16C64(A) PIC16C642 PIC16C65(A-B) PIC16C66 PIC16C662 PIC16C67 PIC16C71 PIC16C710 PIC16C711 PIC16C712 PIC16C72(A) PIC16C73(A-B) PIC16C74(A-B) PIC16C76 PIC16C77 PIC16C773 PIC16C774 PIC16C770 PIC16C771 PIC16C84 PIC16F84 PIC16F870 PIC16F871 PIC16F872 PIC16F873 PIC16F874 PIC16F876 PIC16F Instructions Flash Flash Flash Flash Flash Flash Flash Flash Flash The YAP-II product is complete except for: 1. YAP-II Windows Interface will be updated with graphics showing how eight and fourteen pin PICmicros can be connected and programmed by the YAP-II. 2. This document will be updated with a problem finding matrix to assist in connecting the YAP- II and installing the YAP-II Windows Interface.

3 Please check back at the Wirz Electronics web site at: or Myke Predko s web site: for updates to this document. Note that this document is dated to make it easier for you to determine whether or not the document that you have is downlevel. If you find any problems with this document or have any suggestions for it, please contact Myke Predko at: myke@passport.ca

4 YAP-II Connections Connecting the YAP-II requires two cables; a nine-pin RS-232 cable that connects the YAP to the host computer and DC power, which is 14 Volts or greater and has the ability to source 350 ma. These parts are included in the package you have received. The connections to the host computer are shown in the diagram below along with the different features of the YAP-II: Power for the product should be a 15 Volt, 350+ ma direct current power source connected to the YAP-II via the 2.5 mm power connector built into the board. The power connector has a 1N4001 diode to protect against reversed bias input. The connection to the host computer is an RS-232 nine pin female D-Shell connector. This connector is wired for direct connection from a PC. RS-232 voltages are generated on board and RTS-CTS and DSR-DTR are shorted together to allow terminal emulators with built in handshaking to work properly. This product is designed to work without hardware handshaking.

5 YAP-II Circuitry The schematic for the YAP-II is given below. This schematic represents the programmer section of the board.

6 The following schematic is for the accessories section of the board (on the right hand side when looking at the board with the RS-232 and Power Connector on the left hand side). The accessories section of the board provides ten LEDs, two pulled up buttons, two potentiometers and a speaker for use with your applications. For communications with the host computer, when an application is executing, it can send data serially using the SerOut pin and receive data from the host using the SerIn pin. Like the YAP-II communications interface, the SerOut and SerIn pins provide 1200 bps, 8-N-1, no hardware handshaking communications with the host.

7 The connections from the PIC16C711 to the board connectors include current limiting resistors to protect the PIC16C711 and any circuits that could be back driven when programming and other YAP-II operations are taking place. This is mentioned because RB6 and RB7, which are used for device programming are driven by the PIC16C711 and these pins cannot be driven during programming. If they are, the programming operation will fail.

8 YAP-II Wiring and Host Interface Once the YAP-II is wired to a host computer via the RS-232 cable and power is applied via the AC/DC power supply that comes with the YAP-II, when the Power Switch is moved toward the power connector, the two LEDs on the YAP-II should light. If the LEDs do not light, check your power supply. When a terminal emulator is set up to communicate with the YAP-II, the power up message should be YAP-II Version 0.50 and followed by a > prompt as shown in the following screen shot of HyperTerminal executing. If the terminal emulator does not show this message, check the connection to the computer system followed by the operational parameters of the terminal emulator. The parameters of the terminal emulator must be 1200 bps and 8-N-1.

9 YAP-II Windows Interface The YAP-II can also be controlled by a Microsoft Windows interface which avoids the need for the user to set up a terminal emulator as well as run the manual commands described below. If this application is going to be installed in Windows/NT or Windows/2000 systems, make sure the user installing the application has Administrator Rights. To install the Windows interface, download the following files from the Wirz Electronics web site: YAP-II Windows Version 0 Point 50.CAB Setup.lst setup.exe These files may be zipped (compressed) together. If this is the case, unzip them and place them in a Temporary subdirectory. To do this, the PC s My Computer dialog box should be enabled and will look something like:

10 From the My Computer dialog box, Double Click on (C:) to get something like:

11 From here, click on File, select New and then click on Folder. This will create a new Folder to store the three YAP-II Windows Interface files. The following screen shot shows the creation of the YAP-II Temp subdirectory:

12 Once the subdirectory is created, double click on the folder icon and then copy the three files as shown in: Finally, double click on setup.exe and the YAP-II Windows Interface will start installing. After notification of loading of some applications, the PC s screen will change to:

13 Click on OK followed by the PC and Disk Graphic in the following screen: A new dialog box will be displayed and by clicking on continue will result in the application code being loaded into the PC. Upon completion of the application load, the dialog box in the installation screen will indicate that the load completed. Clicking on OK will clear the screen and place the YAP-II Windows Interface in the PC s Start Menu. To execute the YAP-II Windows Interface, select it from the Start Program List (it will probably be the last item in the list). If the YAP-II is connected correctly and turned on (the two LEDs lit), the following Dialog box should be displayed:

14 If the YAP-II is not connected properly or if it is connected to a serial port other than COM1 (which is the default), then the following screen will be displayed: First change the Com Port: by clicking on the downward arrow to get the list of available serial ports as is shown below: and select the port the YAP-II is connected to. When you select the correct port, the yellow indicator in the top left hand corner of the YAP-II will light and the message will indicate that the

15 Connection has been made to the YAP-II. Once this interface is made, then the YAP-II can be used with the Windows interface. To select files to download into the PICmicro, click on Specify Application hex File. This will bring up the following dialog box that can be used to select different hex files from different folders. This file is checked to ensure that it is in the correct format for the YAP-II and will notify the user if it is not. Once the file is selected, the PICmicro to be programmed can be selected. Currently, the YAP-II Windows interface software only allows the PIC16F84 and PIC16C711 to be specified. This list will be increased in the future, but the current software can support any eighteen pin Flash or program memory based mid-range PICmicro available. With the part and the file specified, the PICmicro can be programmed, its contents verified or checked for blank (in the case of the program memory parts). A percentage complete indicator will come up as downloads take place.

16 Once the application hex file has been programmed into the PICmicro, the part can either be placed into another application circuit or used with the YAP-II s built in circuitry that is described below. The YAP-II has a built in programmable oscillator giving the option of executing code at one, two, four or eight MHz. When these buttons are clicked on the YAP-II Windows Interface, the clock is passed to the PICmicro in the socket (as well as the nineteen pin header) and reset is placed at +5 Volts ( Vdd ) to allow the PICmicro to execute. When this is completed, a special terminal dialog box is presented as shown below which allows the user to communicate with the PICmicro in the application at 1200 bps. This dialog box is terminated by clicking on Stop or pressing Ctrl-C on the PC s keyboard. The YAP-II Windows Interface is designed to be as easy as possible to use, give the user a limited selection of options in order to avoid problems with new PICmicro users and use default information where ever possible to avoid retyping information or going back to the same file folder. Suggestions for improving this interface are desired and should be directed to Myke Predko.

17 Windows Interface for PICmicros other than 18 Pins The YAP-II was designed to natively support 18 pin PICmicro devices with the built in ZIF ( Zero Insertion Force ) socket. Despite this, using the ICSP and PICmicro I/O Sockets on the board, PICmicro devices with pinouts other than 18 pins can be very easily supported. For example, if a PIC16C73B was selected (which is a 28 pin device), the YAP-II Windows Interface background graphic changes to show how this part would be wired in for programming: For Version 0.70, 18, 20, 28 and 40 pin devices are supported. Later versions of the YAP-II Windows Interface will support 8 and 14 pin devices as well. When a new pinout device is selected, the YAP-II Windows Interface Graphic with the appropriate position for the PICmicro will be displayed along with the wiring required for the device. This wiring is accurate, but can be hard to read. To avoid counting squares in the Breadboard section of the YAP-II graphic, the following table outlines how different PICmicros are wired to the YAP-II. Number of Pins Vdd Vss _MCLR (Vpp) 8 (Not Currently Supported) 14 (Not Currently Supported) 18 Use ZIF & 16 5 & & 20 8 & & & 31 1 RB7 (Data) RB6 (Clock)

18 YAP-II Windows Interface Removal Before updating the version of the YAP-II, the pervious version will have to be deleted. This is done by clicking on the Start Bar, followed by Settings and then Control Panel. The Control Panel dialog box for a Windows/98 system is shown below:

19 To remove the YAP-II Windows Interface, click on Add/Remove Programs and select YAP-II Windows Inteface as shown in the following screen shot:

20 Once YAP-II Windows Interface (with the appropriate version number is selected), click on Add/Remove which will start the delete process shown in the screen shot below: From here, click on Yes and the YAP-II Windows Interface will be deleted from your hard file. Once this is done, click on the X in the top right hand corner of the Add/Remove Programs and Control Panel dialog boxes to restore your PC. Once this is done, the latest version of the YAP- II Windows Interface can be loaded onto the PC without danger of interfering with any previous versions.

21 YAP-II Basic Interface Commands The YAP-II is controlled from the Terminal Emulator using the following commands: Command Operation A Ping Return Nothing but Carriage Return/Line Feed B Reset the Program Counter to 0 C Clear the Contents of Flash Memory D Dump 256 Instructions Increment Read Program Counter by 256 E Part Programming Text Send Hex File F Flash Part Programming Text Send Hex File G Get Eight Instructions Starting at Address 0x , 2, 4, 8 Run PICMicro at the Specified Speed The interface itself is designed to run at 1200 bps. This speed was chosen as the fastest standard speed in which the time it takes to receive four bytes (from a hex file) giving an instruction for programming and perform a programming operation in parallel. Running the interface at 1200 bps makes the YAP somewhat slower than other PICMicro programmers but the tradeoff would be to add an external buffer memory which would add to the cost of the device. To program the PIC18F84 that comes with the YAP-II, the following series of commands are used: 1. C followed by Enter is used to Clear the contents of the PIC16F84 s program memory 2. F followed by Enter will put the YAP-II in Flash Programming Mode. This mode will prompt for a hex file to be downloaded into the YAP-II. 3. Downloading the hex file is accomplished by finding the hex file that is to be loaded into the PICmicro in the YAP-II s ZIF socket and then starting a Text Download. If this operation is not initiated within one minute, the YAP-II will time out and display the prompt again. Once the programming operation is complete, the application s circuit can be wired into the connectors and breadboard and then the PICmicro run to test the application. The application development process is demonstrated in more detail later in this document. To execute the application, the 1, 2, 4 or 8 followed by Enter commands are executed. When these commands are received by the YAP-II, the PICmicro is run at the command speed in MHz. During execution, the SerIn and SerOut pins can be used for communications between the host computer and the YAP-II. To stop execution, a Ctrl-C character is sent to the YAP-II. When using a terminal emulator, garbage characters may be displayed on the host computer s display. This is an artifact of the SerIn and SerOut pins changing from passing through to the executing device and back to the YAP-II s controller. The A command is used by the YAP-II Windows Interface software to Ping the YAP-II and test whether or not the YAP-II is connected to the host computer. To download the contents of the PICmicro s program memory, the D command is used to display 256 addresses of program memory. This command keeps a program counter active in the YAP-II so that each time the D command is received, the next 256 addresses of program memory are displayed. To reset this program counter, enter the B command.

22 The D command can be used for verifying the contents of program memory after programming or to do a blank check before programming. To program an PICmicro, the E command is used which behaves exactly the same way from the user s perspective as the F command, but programs the program memory using the Microchip recommended protocols.

23 YAP-II Circuit Interfaces The programming interface circuit consists of three transistors, one diode and seven resistors. Transistor Q6 (along with R10 ) provides a switched power supply to U2, or the part to be programmed. Transistor Q2 and Q5 (along with R7 and R13 ) provide a control to the 13.4 volt power supply to the Vpp pin. The reset circuit is also driven by U1 s RB6 pin that provides reset voltages for when the programmed part is run in a circuit. Resistors R8 and R9 provide the Data and Clock interface to the part being programmed. The resistors are used to provide protection to U1 s pins. To initiate a programming operation, the U1 pins on R8 and R9 (RB5 and RB4, respectively) are pulled low and then Volts is applied to the PICMicro in the socket at U2 or connected to the ICSP port at J4. Once the programming voltage has stabilized, instructions are sent to the PICMicro being programmed. The programmed PICmicro s reset can also be controlled by U1 s RB6 for allowing the PICMicro in the socket to execute. When the PICMicro in the U2 socket is to execute, U1 s RB3 is pulled low, turning on the gate to the programmable oscillator. The U2 socket is designed to provide a method of programming the PICMicro and allowing it to execute freely (clocked by the programmable clock, U7). The U2 socket itself is connected to a nineteen pin interface (J3) that can be connected to circuits on the breadboard attached to the YAP-II PCB or to the second 19 pin socket which provides the built in Accessory Interface. The PICMicro nineteen pin interface is defined as: Pin Function U1 Connection U2 Connection 1 Gnd 2 Vcc 3 _Reset RB6/1K Resistor No Direct Connect 4 YAP-II Oscillator 5 U1 Serial In RA4/1K Resistor 6 U1 Serial Out RA1/1K Resistor 7 U2 RA0 RA0 8 U2 RA1 RA1 9 U2 RA2 RA2 10 U2 RA3 RA3 11 U2 RA4 RA4 12 U2 RB0 RB0 13 U2 RB1 RB1 14 U2 RB2 RB2 15 U2 RB3 RB3 16 U2 RB4 RB4 17 U2 RB5 RB5 18 U2 RB6 Programming Clock RB4/R9 RB6 19 U2 RB7 - Programming Data RB5/R8 RB7 Note that pins 18 and 19 are directly connected to U2 and are used for programming the PICMicro in U2 from U1. There are 1K resistors between the U2 and U1 pins, but there should never be an active driver on J3 s pin 18 and 19 when you are trying to program the part in the U2 socket. If there is an active driver (and this can be an LED on a pull up), then U1 will be unable to overpower it because of the 1K resistors on the ICSP Clock and Data lines. Along with the circuit necessary to program the PICMicro in the U2 socket there is also an ICSP compatible connector at J4. This connector is defined as:

24 Pin Function 1 Vpp Connected to PICMicro programming pin 2 Vcc 3 Gnd 4 ICSP Data 5 ICSP Clock Along with the PICMicro interface, I have also included a set of Accessories to allow new users to try out new applications very quickly, without having to find parts and figure out how to wire them in. J5 is a nineteen pin connector, like J3 and provides an interface to LEDs, buttons, potentiometers, a speaker and some pull ups. Ten LEDs are built into a Bargraph display that are soldered into the board. These LEDs are pulled up by 220 Ohm resistor and to turn them on, they have to be pulled to ground. Two pulled-up buttons are also available along with a potentiometer that acts like a voltage divider. The second potentiometer has all three connections passed to the J5 connector, so different circuits can be built with it. The piezo speaker is connected to J5 through a 0.47 uf capacitor so that the driver is isolated from the speaker (and any transients coming from it). Finally, there are two pull ups for convenience s sake. The pin out of J5 is: Pin Function 1 LED0 2 LED1 3 LED2 4 LED3 5 LED4 6 LED5 7 LED6 8 LED7 9 LED8 10 LED9 11 BUT1 12 BUT2 13 POT1 14 POT2 Wiper 15 POT2 Connection 1 16 POT2 Connection 2 17 Speaker 18 Pull Up 1 19 Pull Up 2

25 YAP-II Sample Application Using Host Terminal Emulator To demonstrate how the YAP-II can be used, start up MPLAB and enter the following application that controls the output state of RB0 according to the input state of RA0. title "testap - Control RB0 from RA0" LIST R=DEC INCLUDE "p16f84.inc" CONFIG _CP_OFF & _WDT_OFF & _XT_OSC & _PWRTE_ON org 0 bsf PORTB, 0 ; Start with the LED on PORTB.0 "off" bsf STATUS, RP0 ; Goto Bank 1 to set Port Direction bcf TRISB ^ 0x080, 0 ; Set RB0 to Output bcf STATUS, RP0 ; Go back to Bank 0 Loop movf PORTA, w ; Simply Transfer PORTA.0 to PORTB.0 movwf PORTB goto Loop end After this application has been built, download it into the PICmicro. First, C lear the Flash program memory using the C Command: Next, start the download process by entering the F :

26 With this done, you can now select the file to download using the Text File Download (not Binary File Download ) option: For HyperTerminal, note that All Files are displayed and not just Test Files. After the file is selected, the programming of the PICmicro will take place automatically. At the end of the programming operation the terminal emulator will look like:

27 Next, the circuit can be built. Because the PIC16F84 is in the ZIF socket, just the connections to RA0 and RB0 are required. For this application, the wiring looks like:

28 Finally, enter in 1, 2, 4 or 8 followed by Enter. The Terminal Emulator will look like: When Ctrl-C is entered to end the application, there may be the garbage characters shown below. To get a valid prompt, enter A followed by Enter.