Tandy 200 Timer

Overview

This article is intended to provide sufficient information to allow you to access the RP5C01 Timer chip in the Tandy 200 without necessarily using any ROM routines.

It is not complete yet

RP5C01: Real Time Clock with Internal RAM

From the Datasheet:

"The RP/RF5C01A are real-time clocks for microcomputers that can be connected directly to buses of microcom- puters with such CPUs as the 8085A or Z80 and allow setting or reading of the clock with the same procedures as for the Read/Write operation for memory.

These products have various features such as clock and calendar counters, alarm functions, and 26 ́ 4bits RAM which can be backed up by batteries. They can then be used as non-volatile RAM."

• Connected directly to CPU
  • 4bit bidirectional data bus : D0 - D3
  • 4bit address input : A0 - A3
• Built-in clock counter (hour, minute, second) and calendar counter (leap year, year, month, day, day-of-the-week)
• Supports both 12-hour AM/PM clock and 24-hour clock
• All clock data expressed in BCD codes
  • ±30 second adjustment function
  • Built-in 26 X 4bits RAM
• Backed up by batteries (minimum:2.2V)
• Outputs alarm signals or timing pulse of 16Hz or 1Hz.
• Packages : 18pin DIP (RP5C01A)