MIL-DTL-62736A

Abstract

This specification covers an Input/Output (I/O) Printed Wiring Assembly, herein referred to as the PWA. This is one of six printed wiring assemblies which comprise the Simplified Test Equipment/Internal Combustion Engine-Reprogrammable (STE/ICE-R) Vehicle Test Meter (VTM) (see Drawing 12259265). <b><u>Intended Use:</u></b> The PWA contains a Universal Asynchronous Receiver/Transmitter (UART; U1) with supporting logic and analog circuitry to facilitate external communications. Transmission and reception baud rate is software selectable, with a range from 150 to 19.2K bits per second. Communication can be in either RS-232-C or RS-485 format through P1-11 (board pins should be designated P1-XX, where XX is pin number), P1-12, and P1-15, P1-16. Software selected circuitry will route RS-485 output back as input for verification. The I/O PWA contains two cascaded Multiply/Divide Units (MDU's, U2 and U3) that are capable of an unsigned 16 bit by 16 bit multiply operation giving a 32 bit result. A 32 bit by 16 bit divide operation, giving a 16 bit result and a 16 bit remainder, is also available. Data is transferred on a 8 bit bus (P1-21 through P1-28). A bus transceiver (U4) isolates the data bus on the PWA from the data bus in the STE/ICE-R system. A &#8722;15 volt DCA source that cannot be pulled above +0.4 volts is available at P1-42. The PWA is military unique because it is designed specifically to be a component of the Simplified Test Equipment/Internal Combustion Engine - Reprogrammable (STE/ICE-R) Vehicle Test Meter (VTM), and to withstand environmental conditions which exceed commercial requirements. <br>