int e l 1.2 GETTING STARTED If you are like most engineers, technicians, hobbyists and humans, and don't like to read manuals, this section is for you. The purpose of this section is to get you off on the right foot. If you are in the High Anxiety Mode and just want to see if the darn chip works, wire the device in the minimum hardware configuration as suggested in the Hardware Configuration chapter of this manual, apply power, and watch what happens. NOTHING! That's because after power is applied to the MCS BASIC-52 device, the program initializes the 8052AH hardware and goes into an AUTO-BAUD search routine.
You must touch the space bar on the serial input device in order to get MCS BASIC-52 to SIGN ON. The message that will appear is *MCS-51 BASIC Vx.x*. If a space character is not the first character sent to the MCS BASIC-51 device after reset, you can spend a lot of time trying to figure out what went wrong. So do yourself a favor, read this section and touch the space bar before you call your local Intel Field Applications Engineer. We received a number of questions asking how the AUTO-BAUD search routine worked. As a result this routine is listed in Chapter 11 of this manual. 1.3 WHAT HAPPENS AFTER RESET? After RESET, MCS BASIC-52:
1) Clears the INTERNAL 8052AH memory 2) Initializes the internal registers and pointers 3) Tests, clears, and sizes the EXTERNAL memory BASIC then assigns the top of EXTERNAL RANDOM ACCESS MEMORY to the SYSTEM CONTROL VALUE MTOP and uses this number as the random number seed. BASIC assigns the default crystal value, 11.0592 Mhz, to the SYSTEM CONTROL VALUE-XTAL and uses this default value to calculate all time dependent functions, such as the EPROM programming timer and the interrupt driven REAL TIME CLOCK. Finally. BASIC checks external memory location 8000H to see if the baud rate information is stored.
If the baud rate is stored, MCS BASIC-52 initializes the baud rate generator (the 8052AH's SPECIAL FUNCTION REGISTER -- T2CON) with this information and signs on. If it isn't stored, BASIC interrogates the serial port input and waits for a space character to be typed. This sounds like a lot, but on the 8052AH, it doesn't take much time. - 2 -