Texas Instruments MSP50C614 manual Introduction

Introduction

5.1 Introduction

The MSP50C6xx development tools gain access to the core controller via a serial scan interface called the Scanport. The basic elements needed to do de- velopment with the MSP50C6xx devices are listed below in Section 5.3. The MSP50C6xx software development tool is included with the MSP scanport in- terface (TI part #MSPSCANPORTI/F) or MSPSI.

The mask programmed MSP50C6xx devices are available in die form to sup- port large volume production quantities. The MSP50C614/605 devices are available in a 100-pin 14⋅20 mm quad-flat pack (QFP) and the MSP50C604 is available in a 64 pin 10⋅10 QFP for medium volume application. The MSP50P614 is an EPROM based version of the MSP50C614, and is available in a 120-pin windowed ceramic pin grid array package. This EPROM based version of the device is only available in limited quantities to support software development. Since the MSP50P614 program memory is EPROM, each per- son doing software development should have several of these PGA packaged devices.

The MSP50C6xx software development tool supports non-real-time debugging by scanning the code sequence through the MSP50C6xx scanport without programming the EPROM. However, the rate of code execution is limited by the speed of the PC parallel port. Any MSP50C6xx device can be used in this debugging mode.

The MSP50P614 EPROM must be programmed to debug the code in real time. The MSP50C6xx software development tool is used to program the EPROM, set a breakpoint, and evaluate the internal registers after the breakpoint is reached. If a change is made to the code, the code will need to be updated and programmed into another device while erasing previous devices. This cycle of programming, debugging and erasing typically requires 10±15 devices to be in the eraser at any one time, so 15±20 devices may be required to operate efficiently. The windowed PGA version of the MSP50P614 is required for this debugging mode.

It is necessary to build preproduction application boards with a zero insertion force PGA socket that allows the device to be easily changed during software development. Use the PGA package pin assignment shown in Figure 1±7. These preproduction boards also have the following requirements for the development tools to function properly. (1) a 10 pin IDC header that connects the MSP50P614 to the MSP Scanport Interface should be provided. (2) the VPP pin of the MSP50P614 must be pulled up to +5V with a diode, so the development tool can apply 12V to this pin. (3) The development tool must be allowed to toggle the reset pin without being loaded by any low impedance reset circuit. This can be accomplished by inserting a 1K ohm resister between

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