The IC–PCR1000 has 128 bytes of electrically-eraseable programmable read-only memory (EEPROM). Icom uses the contents of EEPROM to calibrate your radio so it will operate properly with its unique components. The calibration is done with special equipment that delivers test signals to the radio, and settings are chosen to obtain the best performance.
It turns out that if the IC–PCR1000 is not treated very carefully by the program that controls it, the EEPROM can become corrupted. This will show up as loss of sensitivity, a stuck tuning meter, loss of squelch control, and other defects in performance. The radio is not really usable in this condition, and must be returned to Icom to be recalibrated.
An early, experimental version of MacR–1000 (long before any version released to the public) did, once, corrupt the EEPROM of the radio it was running. This has not happened in any recent version, but bear in mind that corruption is possible, and — once again — you are at your own risk that it is possible.
Because of this vulnerability in the PCR1000, most third-party control programs include a way to read the EEPROM, and save a copy as a backup in case of corruption. MacR–1000 provides this service through the EEPROM window.
When EEPROM is “unlocked” for backup or restoration, it is more vulnerable to corruption than normal. Use this feature at your own risk. Take special care not to cut power from the radio, or unplug the serial connection, while EEPROM is unlocked. Click the lock button again to lock EEPROM as soon as you are done reading or restoring the EEPROM.
Display MacR–1000’s EEPROM window by selecting Show EEPROM (⌘–E) from the File menu. The EEPROM window appears:
![[The EEPROM Window]](EEPROM.png)
The window is dominated by a table for showing the contents of EEPROM. The columns are
- Addr
- The address, or byte number, of the byte displayed in a particular row. This is a base-16 (hexadecimal) number.
- Now
- The value of the byte currently stored at the given address, as a hexadecimal number. This will not be filled in until you have pressed the Read button and the reading of the EEPROM has completed.
- Was
- The value of the byte at the given address, saved in the EEPROM backup file, as a hexadecimal number. This will be blank if you have not read EEPROM and used the Save button to save a backup.
- Typical
- An “average” value for this address, as gleaned from reports of PCR1000 owners. This is for your information only; MacR–1000 provides no way to write these values into your radio.
- Bad
- These are values the PCR1000 tends to put in EEPROM when it has been corrupted. This is presented only for your information.
- Description
- A description of the use of this address, as reported by sources on the ’net. Again, this is presented for your information; it gives an idea of the apparent breadth of control exercised by the EEPROM settings, but there’s not much you can do with the information.
![[Lock, read, and save buttons in EEPROM window]](LockReadSave.png)
Across the top of the window are a series of buttons. The first and largest is the lock button. The PCR1000 must be unlocked before its EEPROM can be read or written to. The button shows the status of the EEPROM lock: The padlock icon is closed when EEPROM is locked, and open when EEPROM is unlocked. For safety, MacR–1000 treats EEPROM-unlocked as a separate mode of operation from “on” and “off;” it will not operate as a receiver while the EEPROM is unlocked.
The Read button asks the PCR1000 for the contents of each of its 128 bytes of EEPROM memory. This will take a few seconds. When reading is complete, the results are displayed in the Now column of the EEPROM table. The Read button is active (available for pushing) only when EEPROM is unlocked.
The Save button saves the contents read from EEPROM to a file named EEPROM.dat in the folder Library/Application Support/PCR-1000 in your home folder. Use this feature to preserve a backup of your radio’s EEPROM in case you need to restore it later. Pressing the Save button again will overwrite the same file. This button is active only when EEPROM has been read from the radio and is showing in the Now column of the EEPROM table. If a saved EEPROM.dat file exists, its contents will be shown in the Was column.
The Restore… button, after it confirms your decision to do so, replaces the contents of the radio’s EEPROM with the contents of the saved EEPROM.dat file. You would do this if you believed your IC–PCR1000’s EEPROM had become corrupted and needed to be restored from a known-good backup. This button is active only when EEPROM is unlocked, and an EEPROM.dat file exists.