Radio Shack TRS-80 26-3501 User Manual

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TRSa) Pocket Comput9f and Cassette Interface
C8t111og Number· 2&3501
. 26-3503
CUSTOM MAMfACTIJlEO FOR RAIJIO SHACK2A DIVISION OF TANDY CORPORATION

Radio Shack TRS-80 26-3501 Specifications

General

Model	TRS-80 26-3501
Category	PDA
Manufacturer	Radio Shack
Input	Keyboard
Memory	32KB RAM
Processor	Zilog Z80
Display	LCD
Connectivity	RS-232
Ports	RS-232
Power Supply	4 AA batteries

Summary

1. Specifications

2. Block Diagram

System Configuration

Lists all components comprising the system architecture.

CPU I and CPU II Overview

Details the roles and functions of the two CPUs.

Power Supply Overview

VDISP Adjustment

3. LSI Signal Descriptions

SC43177 (CPU I) Signals

Detailed pin descriptions for the SC43177 CPU.

SC43178 (CPU II) Signals

Detailed pin descriptions for the SC43178 CPU.

4. Before Servicing

Disassembly Procedure

Steps for safely taking the unit apart.

Repairing Procedure

Guidance for component inspection and replacement.

LSI Replacement

Precautions and steps for replacing LSIs.

Current Consumption Measurement

5. Cassette Tape Interface

6. Cassette Operation

Recording Method

Explains the process of recording data to cassette tape.

Reproduction Method

Cassette Interface Testing

Writing Test Data

Interface Checking Procedure

Repairing the Cassette Interface

8. Circuit Diagram Parts

Circuit Diagram and Signal Positions

Interface Circuit Diagram

9. Parts List for 26-3501

10. Parts List for 26-3503