MC68HC05C8A Datasheet, PDF (70/116 Pages) Motorola, Inc – Microcontrollers

Operating Modes
11.3.2 Self-Check Results
Table 11-2 shows the light-emitting diode (LED) codes that indicate self-check test results.
Table 11-2. Self-Check Circuit LED Codes
PC3
PC2
PC1
PC0
Remarks
Off
On
On
Off
I/O failure
Off
On
Off
On
RAM failure
Off
On
Off
Off
Timer failure
Off
Off
On
On
SCI failure
Off
Off
On
Off
ROM failure
Off
Off
Off
On
SPI failure
Flashing
No failure
All others
Device failure
Perform these steps to activate the self-check tests:
1. Apply 10 V (2 x V_DD) to the IRQ pin.
2. Apply a logic 1 to the TCAP pin.
3. Apply a logic 0 to the RESET pin.
The self-check tests begin on the rising edge of the RESET pin.
RESET must be held low for 4064 cycles after power-on reset (POR) or for a time, t_RL, for any other reset.
For the t_RL value, see 13.8 5.0-V Control Timing.
MC68HC05C8A • MC68HCL05C8A • MC68HSC05C8A Data Sheet, Rev. 5.1
70
Freescale Semiconductor