Datasheet UT69RH051 (Aeroflex) - 2

1.0 INTRODUCTION Table 1. Port 1 Alternate Functions
The UT69RH051 is a radiation-tolerant 8-bit microcontroller
Port Alternate Alternate Function
that is pin equivalent to the MCS-51 industry standard
Pin Name
microcontroller when in a 40-pin DIP. The UT69RH051’s static design allows operation from 1Hz to 20MHz. This data sheet P1.0 T2 External clock input to Timer/ describes hardware and software interfaces to the UT69RH051. Counter 2 P1.1 T2EX Timer/Counter 2 Capture/Reload
2.0 SIGNAL DESCRIPTION
trigger and direction control
VDD:
+5V Supply voltage P1.2 ECI External count input to PCA
VSS:
Circuit Ground P1.3 CEX0 External I/O for PCA capture/
Port 0 (P0.0 - P0.7):
Port 0 is an 8-bit port. Port 0 pins are used compare Module 0 as the low-order multiplexed address and data bus during P1.4 CEX1 External I/O for PCA capture/ accesses to external program and data memory. Port 0 pins use compare Module 1 internal pullups when emitting 1’s and are TTL compatible. P1.5 CEX2 External I/O for PCA capture/
Port 1 (P1.0 - P1.7):
Port 1 is an 8-bit bidirectional I/O port with compare Module 2 internal pullups. The output buffers can drive TTL loads. When the Port 1 pins have 1’s written to them, they are pulled high by P1.6 CEX3 External I/O for PCA capture/ the internal pullups and can be used as inputs in this state. As compare Module 3 inputs, any pins that are externally pulled low sources current because of the pullups. In addition, Port 1 pins have the alternate P1.7 CEX4 External I/O for PCA capture/ uses shown in table 1. compare Module 4
Port 2 (P2.0 - P2.7):
Port 2 is an 8-bit port. Port 2 pins are used as the high-order address bus during accesses to external Program Memory and during accesses to external Data Memory that uses
Table 2. Port 3 Alternate Functions
16-bit addresses (i.e., MOVX@DPTR). Port 2 uses internal
Port Alternate Alternate Function
pullups when emitting 1’s in this mode. During operations that
Pin Name
do not require a 16-bit address, Port 2 emits the contents of the P2 Special Function Registers (SFR). The pins have internal P3.0 RXD Serial port input pullups and drives TTL loads. P3.1 TXD Serial port output
Port 3 (P3.0 - P3.7):
Port 3 is an 8-bit bidirectional I/O port with internal pullups. The output buffers can drive TTL loads. When P3.2 INT0 External interrupt 0 the Port 3 pins have 1’s written to them, they are pulled high by P3.3 INT1 External interrupt 1 the internal pullups and can be used as inputs in this state. As inputs, any pins that are externally pulled low sources current P3.4 T0 External clock input for Timer 0 because of the pullups. In addition, Port 3 pins have the alternate uses shown in table 2. P3.5 T1 External clock input for Timer 1 P3.6 WR External Data Memory write strobe P3.7 RD External Data Memory read strobe 2