Open box GD-77's available from Radioddity

[KA1CM]

Interesting, perhaps the RAM in the RD-5R was "hobbled" in a way to keep it from loading as many RadioIDs as the GD-77. In my experience, before you so kindly upgraded by RD-5R RAM, it held very few contacts. Can you check the GD-77's ability and see if it has a larger contact database option?

I'm going to open the 77 up and do a memory upgrade today, wish me luck, hihi. I believe many people here have the bigger memory version of the 77, either by the special order from Radioditty or DIY work.

[KA1CM]

NMEA has GPS support added, some people have added a GPS module in their radio.

The text strings that GPS modules output on the serial port is in the NMEA format https://en.wikipedia.org/wiki/NMEA_0183

Thank you for clarify, but why special firmware? In STM32 radio (UV380, 1701, etc.) only one firmware cover the GPS and non-GPS unit. Why do we need NMEA firmware for GD77 and 1801, memory problem? What are we treading off for the GPS capability?

[KA1CM]

GD77 and RD5R have identical RAM as this is part of the CPU and they both have the same CPU
GD77 and RD5R also both have 1Mb Flash memory

What the RD5R doesn't have is the 64k EEPROM, which is used to store some of the codeplug.
Correction. It does have the EEPROM. What it doesn't have is the hardware to allow data to be saved when the radio is switched to off

Hi Roger, thank you for clarify, Please check if I understand things correctly. In RD-5R everything is in flash memory (firmware, codeplug, calibration, DMR ID database, etc.) However, for the GD77, some of the codeplug are store in the EEPROM? If that so, GD77 should have more space on the flash memory for DMRID database?

[F1RMB]

Hi,

The RD-5R has an EEPROM, so there is no "extra" space on the GD77, or any supported radio (BTW, the firmware isn't located in the external Flash chip, but in the MCU).
The STM32 based radios don't have EEPROM.

Cheers.
---
Daniel

[SA0BUX]

NMEA has GPS support added, some people have added a GPS module in their radio.

The text strings that GPS modules output on the serial port is in the NMEA format https://en.wikipedia.org/wiki/NMEA_0183

Thank you for clarify, but why special firmware? In STM32 radio (UV380, 1701, etc.) only one firmware cover the GPS and non-GPS unit. Why do we need NMEA firmware for GD77 and 1801, memory problem? What are we treading off for the GPS capability?

I think that the developers have to answer that question, but I guess it could be related to memory.

[F1RMB]

The MK22's "NMEA" versions are supporting the NMEA logging, but it does impact the flash memory storage space (Voice and/or DMRID storage), as you need some space to store that NMEA sentences.
So, if you don't have made any GPS module mod, and not interested in related logging, you can safely ignore such firmware builds.

[KA1CM]

Hi,

The RD-5R has an EEPROM, so there is no "extra" space on the GD77, or any supported radio (BTW, the firmware isn't located in the external Flash chip, but in the MCU).
The STM32 based radios don't have EEPROM.

Cheers.
---
Daniel

Thank you Daniel, So, bacically, both RD-5R and GD77 have the same memory structure.

The MK22's "NMEA" versions are supporting the NMEA logging, but it does impact the flash memory storage space (Voice and/or DMRID storage), as you need some space to store that NMEA sentences.
So, if you don't have made any GPS module mod, and not interested in related logging, you can safely ignore such firmware builds.

I might want to do the GPS mod in the future. Is it save to say, If I get the GPS mod done I will then need the NMEA version of the firmware?

[F1RMB]

Thank you Daniel, So, bacically, both RD-5R and GD77 have the same memory structure.

Yes, it's identical.

I might want to do the GPS mod in the future. Is it save to say, If I get the GPS mod done I will then need the NMEA version of the firmware?

No, GPS support is available out of the box in the non NMEA firmwares. NMEA builds only add NMEA logging (which permits to extract logged tracks/data).

[KA1CM]

Thank you Daniel, So, bacically, both RD-5R and GD77 have the same memory structure.

Yes, it's identical.

I might want to do the GPS mod in the future. Is it save to say, If I get the GPS mod done I will then need the NMEA version of the firmware?

No, GPS support is available out of the box in the non NMEA firmwares. NMEA builds only add NMEA logging (which permits to extract logged tracks/data).

Thank you, Daniel. Great info.

P.S. Memory upgrade on the GD77 went well, a little bit harder to dissemble the radio than the RD-5R, but not thing major.